Oil Processing Facilities

MAERSK CURLEW - Book B: Oil Processing Facilities 002 / MAY 2010

Cover Page

Book B Oil Processing Facilities MAERSK CURLEW

This manual is the property of the Companies within Maersk FPSOs and is for the use of designated staff only.

THIS IS A CONTROLLED PUBLICATION

Revision requests and comments should be forwarded to: http://siriusportal.apmoller.net

ID: M-CPH-1171-01417_EN_Section_0.01.doc

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Table of Contents


Cover Page

002 / MAY 2010

Table of Contents

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Introduction .01 Objectives for this Manual .02 Administration .03 Manual Structure .04 Definition System Overview .01 Introduction .02 Process Flow Summary Process Description .01 Subsea System - Overview .02 Test and Production Manifolds .03 Test Separator V-1005 .04 HP Separator V-1001 .05 HP Crude Oil Heater E-1001 .06 MP Separator V-1002 .07 MP Crude Oil Heater E-1002 .08 LP Separator V-1003 .09 Produced Water Transfer Pumps P-1002A/B .10 Crude Oil Transfer Pumps P-1001A/B .11 Electrostatic Coalescer V-1004 .12 Export Crude Oil Cooler E-1004 Equipment Description .01 Test and Production Manifolds .02 Test Separator V-1005 .03 HP Separator V-1001 .04 HP Crude Oil Heater E-1001 .05 MP Separator V-1002 .06 MP Crude Oil Heater E-1002 .07 LP Separator V-1003 .08 Produced Water Transfer Pumps P-1002A/B .09 Crude Oil Transfer Pumps P-1001A/B .10 Electrostatic Coalescer V-1004 .11 Export Crude Oil Cooler E-1004 Operating Procedures .01 Cold Start-up of the Oil Processing Facilities .02 Hot Start-up of the Oil Processing Facilities .03 Normal Running

ID: M-CPH-1171-01417_EN_Section 0.02

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Table of Contents

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.04 Planned Shutdown of the Oil Processing Facilities .05 Process and Emergency Cause and Effect Charts .06 Pressure Safety Valve Five Key Interlock Operations Isolation/Reinstatement Procedures .01 Oil Processing Facilities, Boundary Isolation, Flushing, Draining and Nitrogen Purging Operations .02 Test Separator V-1005 .03 HP Separator V-1001 .04 HP Crude Oil Heater E-1001 .05 MP Separator V-1002 .06 MP Crude Oil Heater E-1002 .07 LP Separator V-1003 .08 Produced Water Transfer Pumps P-1002A/B .09 Crude Oil Transfer Pumps P-1001A/B .10 Electrostatic Coalescer V-1004 .11 Export Crude Oil Cooler E-1004 .12 Oil Processing Facilities Boundary Reinstatement

ID: M-CPH-1171-01417_EN_Section 0.02

002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010 002 / MAY 2010

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Introduction


Introduction 1.01 1.02 1.03 1.04

Objectives for this Manual Administration Manual Structure Definition

ID: M-CPH-1171-01417_EN_Section_1.doc

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Introduction

1.01 Objectives for this Manual

The objective of this Operating Procedures Manual is to provide the Plant Operators with detailed information and instructions for the safe and efficient operation of the process facilities on the Curlew Field Floating, Production, Storage and Offloading (FPSO) vessel.


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Introduction

1.02 Administration

This document is a controlled publication and all revision requests and suggestions should be submitted via the SIRIUS portal under: http://siriusportal.apmoller.net

Language

The English version prevails if conflicts are found between different language versions.

Controlled Publication

This means that the manual is identified by a distinct document number and a track record is kept regarding the below: Manual’s Edition number and issue date Language version Number of Volumes of the manual

Revisions

Revision Requests must be in the English language. To submit a revision request for this document go to the SIRIUS portal under http://siriusportal.apmoller.net and find the document by using the search options. Open a model where the document is attached and right-click, which will open a drop-down menu. Click on “Request revision” to open the revision request form.

Fill in and submit the form as per included instructions. Shortly after submitting the revision you will receive an email containing the unique number given to your request to use for queries and updates. You will be notified upon completion or rejection. Weekly status updates on revisions will be sent to the OIM of each offshore unit. Progress on all open revisions can be followed under: http://drilling-fpsos.apmoller.net/sirius


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Introduction

1.03 Manual Structure

The Operating Procedures Manual for the Curlew FPSO comprises two Volumes; Volume 1 Process and Volume 2 Marine. Each Volume is subdivided into a series of standalone Books, each addressing one or more associated systems, as follows:

Volume 1 Process

Book A Subsea Facilities Book B Oil Processing Facilities Book C Gas Processing Facilities Book D Produced Water and Sand Jetting Facilities Book E Water Injection Facilities (Not Used - Future) Book F Flare and Vent Systems Book G Main Power Generation and Distribution Book H Cooling Medium System Book I Heating Medium System Book J Compressed Air and Nitrogen Systems Book K Fuel Gas System Book L Seawater System Book M Chemical Injection Systems Book N Export Pipelines (Not Used) Book O Laboratory Procedures Book P Glycol Regeneration System Book Q Drainage Systems

Volume 1 Process (Continued)

Volume 2 Marine

Book A Crude Oil Storage and Offloading Book B Ballast Systems Book C Crude Oil Washing Book D Marine Power Generation (Not Used) Book E Compressed Air Book F Seawater Service Systems Book G Freshwater Systems Book H Main Boiler Systems Book I Fuel Oil (Not used) Book J Diesel Oil Book K Lube Oil Book L Bilge and Sludge Systems Book M Soil System Book N Stern Thruster (Not Used) Book O Main Engine System (Not Used) Book P Deck Equipment Book Q Inert Gas Facilities Each Volume provides a description of the system and its associated equipment and provides detailed start-up, operation and shutdown procedures. In addition, isolation/reinstatement procedures are also included in Volume 1 for all of the main process plant.


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Introduction

1.04 Definition

Definition of this Manual is in accordance with the ISO 8402 Standard. Those definitions which are not included in that standard are in accordance with the terms of ISO 9004 or the Company’s own definitions.

Approval

Statement or signature from an authorised person that a product or service complies with specified requirements or that a defined series of planned actions may be initiated.

Area Manager

The person designated to manage the activities of Maersk FPSOs Floating Production Division in a specific area.

Maersk Operational Documentation Control

The organisational unit designated by the Operations Manager to conduct the control of documents and publications issued under the Maersk FPSOs - Floating Production Division Operational Documentation Management System.

Company Policy

Any of the policies stated within the framework of the Management System Manuals and explicitly authorised by the Maersk FPSOs Floating Production Division Operations Manager.

Offshore Installation Manager (OIM)

That person on an offshore unit who has the highest authority (in some publications this person may be referred to as the Person in Charge).


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System Overview


System Overview 2.01 2.02

Introduction Process Flow Summary

Figure 2.01

Topsides Processing Facilities Overview


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System Overview

2.01 Introduction

The Curlew FPSO is designed to accept well fluids from the Curlew subsea wells and process fully stabilised or ‘dead’ crude for cargo tank storage with export via shuttle tankers. The Curlew subsea development includes the Curlew D field, a gas/condensate field in Block 29/7 of the Western Central Graben and Curlew B field, an under-saturated oil reservoir located approximately 4km west of Curlew D. Total Curlew production is currently from Curlew D wells as Curlew B is no longer producing and all indications are that it is dead. The topsides process facilities include the oil stabilisation plant, gas compression train, dehydration equipment for sales gas export and the produced water treatment package. Produced water treatment facilities are provided to clean up the produced water from the well stream fluids enabling the polished produced water to be discharged overboard. Detailed information on the Produced Water Treatment facilities is provided in Volume 1 Book D of the Operating Procedures Manuals. Figure 2.01 provides an overall simplified schematic of the main topsides oil processing facilities. Topside production routing is configured such that Curlew D wells production is routed to the HP Separator and the Curlew B well production to the MP Separator. The oil stabilisation facilities consist of a single separation train with three stages of flash separation and an electrostatic coalescer which reduces the water content in the crude oil to 0.5% (volume). A single gas compression train is provided configured as three stages with a single train of gas dehydration between the 2nd and 3rd stages of compression. Detailed information on the Gas Processing facilities is provided in Volume 1 Book C of the Operating Procedures Manuals. The Oil Stabilisation Facilities are located in areas M01, M02, and M03 of the Process Deck and comprise the following main items of equipment: 

Test Separator, V-1005



HP Separator, V-1001



HP Crude Oil Heater, E-1001



MP Separator, V-1002



MP Crude Oil Heater, E-1002



LP Separator, V-1003



Produced Water Transfer Pumps, P-1002A/B



Crude Oil Transfer Pumps, P-1001A/B


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System Overview 2.01 Introduction (Continued)

2.02 Process Flow Summary



Electrostatic Coalescer, V-1004



Coalescer Power Pack, L-1001



Export Crude Oil Cooler, E-1004

Well fluids from the Curlew B and D flow, via subsea flowlines and flexible risers, to the FPSO turret. Individual production choke valves, operated from the Central Control Room (CCR) are located at the subsea xmas trees and within the turret to control the flow from each well. The individual well design flowrates are 20,000bpd of fluids with a minimum operational flowrate of 13,000bpd. The well flowlines are designed for bullheading of scale inhibitor squeeze chemicals back from the FPSO to each well with a maximum pump discharge pressure of 356barg which exceeds the maximum shut-in wellhead pressure of 327barg for the Curlew ‘B’ well and 354barg for the Curlew ‘D’ wells. Although sand production is not anticipated, sandwashing connections are provided for all separation vessels included in the oil processing facilities. Chemical injection points are provided on the topsides flowlines to enable methanol, demulsifier, antifoam and corrosion inhibitor to be injected (refer to Volume 1, Book M of the Operating Procedures Manuals). The arrival temperature of the Curlew fluids under normal operation is designed to be a minimum of 60°C, this temperature being set by the cloud point temperature of the live crude to minimise the possibility of wax deposition. Production and test manifolds within the turret collect fluids from all wells. The two flowlines from the Curlew D subsea production facilities are either routed directly through a dedicated production manifold in the swivel to the HP production separator or directed to the test manifold. The fluids from the test manifold pass through a separate path within the swivel to the Test separator in the Oil Stabilisation Facilities. In the event of any problems with the Test or Production swivels, crossover between the HP and Test production manifold is provided to facilitate an alternative back-up production flowpath via the ‘redundant’ Water Injection Swivel, thus allowing continued operation of the Curlew field. The operation of this crossover is further detailed in Sections 3.02 and 4.02. Due to its lower wellhead pressure the single Curlew B flowline is routed through the swivel to either the MP separator or the Test separator via separate manifolds. The Oil Processing Facilities are designed to handle 75,000BPD of fluids, with a maximum oil rate of 45,000BOPD, a maximum water rate of 30,000BWPD and a maximum gas export rate of 110MMSCFD.


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System Overview 2.02 Process Flow Summary (Continued)

The oil production train comprises three stages of separation, namely the HP Separator V-1001, MP Separator V-1002 and LP Separator V-1003. Curlew fluids are routed to the HP Separator, V-1001. Partially stabilised crude from Curlew then enters the MP Separator, V-1002, for further stabilisation. Each vessel is equipped to achieve three-phase separation of gas, hydrocarbon liquid and produced water. Produced gas from the vessels flows under pressure control to the gas compression facilities. Demulsifier and anti-foam injection points are provided on the inlet headers to the Test separator, HP separator and MP separator to enhance the separation process. Crude oil heating is provided between the separation stages. The HP Crude Oil Heater E-1001 is installed on the oil outlet from the HP separator (upstream of tie in with Test separator fluids) and the MP Crude Oil Heater E-1002 is located on the outlet from the MP separator. The HP crude oil heater is a shell and tube heat exchanger and the MP crude oil heater is designed as plate type heat exchanger. Both heaters use heating medium to increase the temperature of the crude oil to the desired temperature to enhance separation. The HP, MP, LP and Test separators are designed so that the liquid carryover in the gas outlet stream from the vessels does not exceed 0.10 US gals per MMSCF. If the Oil Processing Facilities are operating efficiently, the water content in the oil outlet streams from these vessels should not exceed 2.0% (volume). The fully stabilised crude oil from the LP separator, together with any produced water carried over from the vessel, is pumped to the electrostatic coalescer. The coalescer operates at a pressure approximately 5barg greater than the LP separator and is designed to ensure that the water content of the crude is reduced to less than 0.5% (volume). If required, the crude oil passing through the coalescer can be dehydrated to a BS&W of 0.3% as the salt content of the crude oil export must not exceed 500mg/lt. However, it is anticipated that the salt content of the crude oil will be less than 300mg/lt if the electrostatic coalescer is set to reduce the water content of the crude to less than 0.5%. The water removed in the coalescer is returned under level control to the MP crude oil heater. The dehydrated crude from the coalescer flows through the Export Crude Oil Cooler E-1004 before entering the FPSO storage facilities. The cooler is a plate type exchanger which uses cooling medium to cool the fully stabilised crude to 30oC for storage. The separators, crude oil heaters and coalescer included in the oil processing facilities ensure that the stabilised crude oil exported to the shuttle tankers has a maximum True Vapour Pressure (TVP) of 0.83barg at 26.67oC. A design margin has been incorporated into the capacity of the HP and MP crude oil heaters to ensure that the TVP can be achieved during conditions of variable flow.


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System Overview 2.02 Process Flow Summary (Continued)

Well Testing is performed using the Test separator. Existing vortex meters located on the oil outlet of the first stage separators (HP and Test) are utilised as part of new facility for production allocation metering. This will comprise a fast loop crude sampling pump system incorporating in-line density and BS&W meters.


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Figure 2.01: Topsides Processing Facilities Overview

Process Description


Process Description 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12

Subsea System Overview Test and Production Manifolds Test Separator V-1005 HP Separator V-1001 HP Crude Oil Heater E-1001 MP Separator V-1002 MP Crude Oil Heater E-1002 LP Separator V-1003 Produced Water Transfer Pumps P-1002A/B Crude Oil Transfer Pumps P-1001A/B Electrostatic Coalescer V-1004 Export Crude Oil Cooler E-1004

Figures 3.01 3.02 3.03

Production Subsea Tree with Umbilical Interface (Curlew Well DP1 - Typical) Turret – Process and Control Interface Schematic Oil Stabilisation Train Schematic – Process Facilities


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Process Description 3.01 Subsea System Overview

Wells have been drilled at two subsea locations (the Curlew B and D Drilling Centres). Crude oil flows from the remaining subsea wells, via subsea flowlines and flexible risers to the FPSO turret. Each production well is connected to the FPSO by a single flowline with a production choke mounted within the FPSO turret. A subsea choke is fitted to the xmas trees for all wells. The Subsea Control System is a multiplexed electro-hydraulic system. The subsea facilities are monitored and controlled from the Local Equipment Room (LER), via the Process Control System (PCS). All electrical monitoring and control signals are performed from the Master Control Station (MCS) located in the LER. The MCS interfaces with the Integrated Control and Safety System (ICSS) to allow the control of the subsea facilities to be transferred to the PCS. Valves operated at each production xmas tree are as follows:        

Production Wing Valve (PWV) Annulus Wing Valve (AWV) Production Upper Master Valve (PUMV) Annulus Master Valve (AMV) Annulus Crossover Valve (AXOV) Subsurface Safety Valve (SSSV) [Downhole Safety Valve] Methanol Injection Valve (MIV) Subsea Choke Valve

The system also provides constant monitoring of the following functions at each well:        

Downhole Pressure Downhole Temperature Annulus Bore Pressure Wellhead Pressure Wellhead Temperature Flowline Pressure Subsea Choke Position Topsides Choke Position

The ICSS controls all the riser Emergency Shutdown Valves (ESDVs) located in the turret. These shutdown valves are the first barrier on the FPSO from the subsea wells. All safety critical ESD signals to the turret are hardwired across a slip ring system incorporated at the swivel in the turret. Data monitoring and non-critical functions are operated via high security telemetry between the CCR and the turret turntable.


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Process Description 3.01 Subsea System Overview (Continued)

3.02 Test and Production Manifolds (Refer to Figure 3.03)

Further details of the subsea wellheads and controls are provided in Volume 1, Book A – Subsea Facilities. Refer also to the following figures at the end of this Section: 

Figure 3.01: Production Subsea Tree with Umbilical Interface (Typical)



Figure 3.02: Turret - Process and Control Interface Schematic

Well fluids from any subsea production well flow through its subsea flowline and riser to the FPSO turret. The riser enters the base of the turret and passes vertically up through the turret to its riser emergency shutdown valve. The pipework for the well then leads the well fluids through a downstream HIPS valve on the flowline to the remotely operated choke valve. The Curlew flowlines are then divided into separate feeds for the test and production turret located manifolds. Each supply to the manifolds is fitted with a manual diverter valve. Under normal conditions, when the production swivels are trouble and leakage-free, the Curlew D production fluids are routed to the HP Separator and the Curlew B wellfluids routed to the Test Separator. When producing Curlew through the HP swivels to the Test separator via the crossover manifold, the terminations to the routing switches on the Curlew routing valves 07-XV-110 and 07-XV-402 (flowline DP2) as well as 07-XV-210 and 07-XV-403 must be switched over. This is to ensure that the shutdown signal from the Test separator is correctly routed. The turret located manifolds are constructed circumferentially around the centrally positioned facility termed the swivel. The swivel receives crude from each manifold into its lower-most inlet ports, transferring the well fluids upwards through internal concentric annuli to the upper outlet ports. The outlet ports are arranged one upon another, maintaining isolated flowpaths for the test and production crude, and link directly across to the respective test and production manifolds which are part of the FPSO structure. The uppermost section of the swivel, which contains the outlet ports, is free to rotate with the FPSO, while its lowermost inlet ports are attached to the turret and therefore fixed in relation to the seabed. The swivel also provides the link between the FPSO and turret for the gas export and water injection manifolds, however the water injection manifold is not normally in use. The test and production manifolds on the FPSO transfer the well fluids to the test, HP or MP separators respectively for the three-phase separation of crude oil, produced water and gas.


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Process Description 3.02 Test and Production Manifolds (Continued) (Refer to Figure 3.03)

Chemical injection facilities are provided on the FPSO to direct the following chemicals into the inlet headers for the test, HP and MP separators downstream of the turret:  

Demulsifier Antifoam

Chemical injection facilities are provided on the FPSO to direct the following chemicals into the production facilities within the turret and subsea wellheads:    

Methanol Corrosion Inhibitor Wax Inhibitor Scale Inhibitor

Details of all chemical injection facilities on the FPSO are provided in Volume 1 Book M. 3.03 Test Separator V-1005 (Refer to Figure 3.03)

The Test separator is no longer utilised as a well testing facility and is dedicated solely for production of Curlew fluids. The function of the Test separator is to receive Curlew D production fluids from the subsea well(s) and conduct three-phase separation of the reservoir fluid into the following constituent parts:   

Crude Oil Produced Water Produced Gas

The Test separator operates at 39barg and 60 to 70oC and is designed to process up to 20,000BOPD. Crude oil from the test manifold enters the Test separator and is immediately subjected to a reduction in pressure and velocity in the vessel. The reduction in pressure and the retention time of the Test separator facilitates an efficient three-phase separation to take place within the vessel. An internal weir has been installed to aid separation, and the instrumentation which controls the oil/water interface in the bulk side of the separator is used to increase (or decrease) the residence time of the well fluids. The oil and produced water components are drawn off either side of the weir from within their respective operating levels for further processing. The off-gas leaves the Test separator from the outlet nozzle positioned on top of the vessel. A Vortex Meter, 10-FT-0515, is installed in the gas outlet line and data from this instrument is transmitted to the PCS. The gas then commingles with the process gas from the HP separator and passes forward to the Gas Compression Facilities for further processing.


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Process Description 3.03 Test Separator V-1005 (Continued) (Refer to Figure 3.03)

The crude oil from the Test separator is measured by a Vortex Meter, 10FT-0519 with data transmitted to the PCS. The crude then passes forward to the MP separator for partial stabilisation or on to the process inlet for the MP crude oil heater for preheating prior to entering the LP separator for full stabilisation. The produced water from the Test separator is measured by a Vortex Meter, 10-FT-0521 with data transmitted to the PCS. The produced water then passes directly to the test hydrocyclone in the Produced Water Package for clean-up. However, a crossover has been provided between the Test separator and HP Hydrocyclone. When Curlew produced water rates are in excess of 5000 BWPD, repositioning of spectacle blinds and adjustment of control switch, 40-HS-4001A, allows produced water from the Test separator to be routed to the HP Hydrocyclone. The oil, gas and produced water metering facilities at the Test separator allow Curlew fluids to be measured for the purpose of metering allocation. Sampling of the incoming crude to the Test separator provides the Base Sediment and Water readings (BS&W). Sampling and analysis of the produced gas exiting the Test separator provides the Carbon Dioxide (CO 2 ), Hydrogen Sulphide (H 2 S) and composition of the gas.

3.04 HP Separator V-1001 (Refer to Figure 3.03)

The function of the HP separator is to receive production fluids from the subsea well(s) and conduct three-phase separation of the reservoir fluid into the following constituent parts:   


The HP separator operates at approximately 39barg and 35oC to 60oC and is designed to process up to 37000BOPD. Crude oil enters the separator and is immediately subjected to a reduction in pressure and velocity in the vessel. The designed retention time of the HP separator allows three-phase separation to take place within the vessel. An internal weir has been installed in V-1001 to aid separation, and the instrumentation which controls the oil/water interface in the bulk side of the separator is used to increase (or decrease) the residence time of the well fluids. The oil and produced water components are drawn off either side of the weir from within their respective operating levels for further processing. The flowrates of crude oil, produced water and produced gas from the HP separator are accurately measured by vortex meters on leaving the vessel. The crude from the HP separator passes to the HP crude oil heater for pre-heating prior to entering the MP separator.


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Process Description

3.04 HP Separator V-1001 (Continued) (Refer to Figure 3.03)

The produced water from the HP separator is directed to the HP hydrocyclone in the produced water package for clean-up. Conversely to the arrangement with the Test separator, produced water from the HP separator can be routed to the Test hydrocyclone. When Curlew production is less than 5000 BWPD, the HP hydrocyclone is used. The produced gas leaves the HP separator from the outlet nozzle positioned at the top end of the vessel. Downstream of the HP separator the produced gas passes to the inlet gas cooler included in the Gas Compression Facilities for further processing.

3.05 HP Crude Oil Heater E-1001 (Refer to Figure 3.03)

The HP crude oil heater is a conventional shell and tube heat exchanger designed to raise the temperature of the partially stabilised crude from the HP separator. The warmed crude oil leaving the crude oil heater is fed to the MP separator for further processing.

3.06 MP Separator V-1002 (Refer to Figure 3.03)

The MP separator is provided to receive the well fluids from the Curlew B subsea well and semi-dry, preheated crude oil from the HP crude oil heater. Well fluids from the Curlew D subsea wells, the partially stabilised crude from the Test separator, is also directed to V-1002. In addition, the 2in common discharge line from the produced water transfer pumps is hardpiped to the MP separator to dispose of the produced water from these facilities. Three-phase separation of the fluids occurs inside the MP separator into the following components:   


The MP separator operates at approximately 10barg and 48 to 67oC and is designed to process up to 49000BOPD. Wellfluids, produced water and Crude oil enter the separator and are immediately subjected to a reduction in pressure and velocity in the vessel. The designed retention time of the MP separator allows three-phase separation to take place within the vessel. An internal weir has been installed in V-1002 to aid separation, and the instrumentation which controls the oil/water interface in the bulk side of the separator is used to increase (or decrease) the residence time of the well fluids. The oil and produced water components are drawn off either side of the weir from within their respective operating levels for further processing. The flowrates of crude oil, produced water and produced gas from the MP separator are accurately measured by vortex meters on leaving the vessel. The partially stabilised crude from the MP separator passes to the MP crude oil heater for pre-heating prior to entering the LP separator for full stabilisation.


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Process Description

3.06 MP Separator V-1002 (Continued) (Refer to Figure 3.03)

The produced water from the MP separator is directed to the MP hydrocyclone in the produced water package for clean-up.

3.07 MP Crude Oil Heater E-1002 (Refer to Figure 3.03)

The MP crude oil heater is a conventional plate heat exchanger designed to raise the temperature of the crude flowing to the downstream LP separator. This is essential, as the LP separator must be capable of producing fully stabilised crude oil suitable for storage on the FPSO and export to the shuttle tankers.

The produced gas leaves the MP separator from the outlet nozzle positioned at the top end of the vessel. Downstream of the MP separator the produced gas passes to the MP compressor suction cooler in the Gas Compression Facilities for further processing.

Typically, the crude temperature is raised to 65 to 68oC when passing through the cold side of the heater by heating medium at 5barg and 120oC passing through the hot side of the exchanger. 3.08 LP Separator V-1003 (Refer to Figure 3.03)

The LP separator is provided to receive the preheated crude oil from the MP crude oil heater and conduct three-phase separation of the fluids into the following components:   


The LP separator vessel has a design pressure and temperature of 16barg and -30/+85oC respectfully, and normally operates at 1.1barg and 67oC. Preheated crude oil enters the second stage separator and is subjected to a further reduction in pressure and velocity in the vessel. The designed retention time of the LP separator allows three phase separation to take place within the vessel. An internal weir has been installed in V-1003 to aid separation, and the instrumentation which controls the oil/water interface in the bulk side of the separator is used to increase (or decrease) the residence time of the fluids. The oil and produced water components are drawn off either side of the weir from within their respective operating levels for further processing. The crude oil recovered in the LP separator passes out of the bottom of the vessel and flows to the oil transfer pumps which are located directly below the separator. The produced water from the LP separator is directed to the produced water transfer pumps also located beneath the separator. The evolved gas leaves the vessel from a single outlet nozzle at the top of the vessel and flows under pressure control to the LP compressor cooler in the Gas Compression Facilities for further processing.


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Process Description 3.09 Produced Water Transfer Pumps P-1002A/B (Refer to Figure 3.03)

The produced water transfer pumps are provided to receive the produced water from the LP separator at a pressure of 1.1barg and pump the liquids back to the MP separator at a discharge pressure of approximately 11barg. The produced water transfer pumps are single stage, centrifugal pumps driven by 18.5kW electric motors. Each pump is rated at 16.5m3/hr. The two pumps operate on a duty/standby basis.

3.10 Crude Oil Transfer Pumps P-1001A/B (Refer to Figure 3.03)

The crude oil transfer pumps draw the wet crude from the LP separator at a pressure of 1.1barg and pump the crude to the electrostatic coalescer for further processing at a discharge pressure of approximately 7barg.

The two identical crude oil transfer pumps are single stage, centrifugal pumps driven by 90kW electric motors. Each pump is rated at 326m3/hr. The 100% capacity pumps operate on a duty/standby basis. A dedicated flow control valve 10-FCV-0328 is fitted on the common discharge line from both crude oil transfer pumps to provide minimum flow protection to the Transfer Pumps by recycling a controlled flow of crude oil via 10-FICA-0328 back to the LP separator. 3.11 Electrostatic Coalescer V-1004 (Refer to Figure 3.03)

The coalescer is designed to reduce the water-in-oil content of the crude oil for export/storage to 0.5% (volume). The demulsifier which can be injected into the test and production manifolds at the turret helps break down the oily film around water molecules in the upstream separation trains, but further treatment in the coalescer is required to complete the operation. The coalescer operates by breaking down oil/water emulsions with the use of a high voltage electric field. Note: An emulsion can be depicted as water molecules surrounded by a thin film of oil, held together by surface tension. The oil film requires to be broken to allow the water molecules to coalesce. The coalescer operates in a completely flooded condition at all times. The crude oil and water emulsion enters the coalescer at the bottom and is ducted to below the electrostatic grids where it is then evenly distributed along the length of the vessel. As the crude/emulsion moves vertically towards the outlet collector tray it passes between the high voltage grids where an intense electrostatic field exists. This results in suspended water droplets within the crude becoming charged and distended. The charged water particles are attracted to each other at opposite poles and as they collide they coalesce to form larger droplets. These larger water droplets fall towards the bottom of the vessel against the general direction of flow.


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Process Description

3.11 Electrostatic Coalescer V-1004 (Continued) (Refer to Figure 3.03)

The dry crude oil passes out of the top of the coalescer and is fed to the export crude oil cooler for further processing.

3.12 Export Crude Oil Cooler E-1004 (Refer to Figure 3.03)

The export crude oil cooler is a plate type exchanger provided to cool the dehydrated crude oil from the electrostatic coalescer to 30oC before its arrival at the cargo oil storage tanks on the FPSO.

The produced water passes out of the bottom of the coalescer and is directed back to the MP crude oil heater.

The cooler utilises cooling medium (70% / 30% water/glycol) as the heat exchange material. The outlet temperature of the crude leaving the coolers is controlled by a temperature control valve located on the cooling medium return line.


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Figure 3.01 Production Subsea Tree with Umbilical Interface (Curlew Well DP1 - Typical)

Figure 3.02: Turret – Process and Control Interface Schematic

Figure 3.03: Oil Stabilisation Train Schematic – Process Facilities

Equipment Description


Equipment Description 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11

Test and Production Manifolds Test Separator V-1005 HP Separator V-1001 HP Crude Oil Heater E-1001 MP Separator V-1002 MP Crude Oil Heater E-1002 LP Separator V-1003 Produced Water Transfer Pumps P-1002A/B Crude Oil Transfer Pumps P-1001A/B Electrostatic Coalescer V-1004 Export Crude Oil Cooler E-1004


Page 1 / 36


Equipment Description 4.01 Test and Production Manifolds (Refer to P&ID Drgs CUR-MAS-PB-20022-001, CUR-MAS-TP-42002-001 and CUR-MAS-TP-42035-001)

During normal operation reservoir fluids from Curlew D and Curlew B production wells flow through individual risers to the turret before passing on to the test and production manifolds. Production from DP3 can pass through either the DP1 or DP2 flowlines; normal production from DP3 would pass through DP2 flowline. Well fluids from Curlew DP1 production line pass to the turret through an 8in riser and flowline which is provided with the following flow control and shutdown isolation valves: Riser Shutdown Valve Flowline Shutdown Valve Choke Valve Production Diverter Valve Test Diverter Valve

- 07-XV-200 - 07-XV-205 - 07-PCV-209 - 07-XV-210 - 07-XV-403

Well fluids from Curlew DP2 production line pass to the turret through an 8in riser and flowline which is provided with the following flow control and shutdown isolation valves: Riser Shutdown Valve Flowline Shutdown Valve Choke Valve Production Diverter Valve Test Diverter Valve

- 07-XV-100 - 07-XV-105 - 07-PCV-109 - 07-XV-110 - 07-XV-402

Well fluids from Curlew BP1 production line pass to the turret through a 6in riser and 8in flowline which is provided with the following flow control and shutdown isolation valves: Riser Shutdown Valve Flowline Shutdown Valve Choke Valve Production Diverter Valve Test Diverter Valve

- 07-XV-300 - 07-XV-305 - 07-PCV-309 - 07-XV-310 - 07-XV-404

The spare production line passes to the turret as a 12in riser and 12in flowline which is provided with the following flow control and shutdown isolation valves: Riser Shutdown Valve Flowline Shutdown Valve Choke Valve Isolation Valve


- 07-XXV-0500 - 07-XV-0505 - 07-PCV-0509 - 07-XV-0510

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4.01 Test and Production Manifolds (Continued)

Crossover lines are provided to facilitate flow from the spare production line to be routed through the water injection swivel, when there are problems with the production or test swivels. During this time Curlew D production will remain to be through the production or test swivel to allow positive isolation and maintenance of whichever swivel requires it. During the utilisation of the water injection swivel, a further crossover is installed outside of the turret to the spare production line to be routed to HP separator and Curlew fluids routed to the Test separator. At this time, there is no need for any crossover outside of the turret. Curlew D production is via the production swivel to the HP separator and well testing is via the test swivel to the Test separator. Refer to Figure 3.8 Crude Production Flowline System Valves and Spectacle Blind Status. All four production risers are protected by a series of layers of armoured protection with an inner carcass. The inner carcass is not pressure retaining and is designed to prevent the collapse of the pressure sheath on top of it. Any pressure in the carcass is safely vented to atmosphere via two dedicated carcass vent lines located upstream of the riser valves. Any leakage from the carcass passes through these vent lines which are permanently locked open to an atmospheric vent header. The Riser Shutdown Valve is hydraulically actuated and is located upstream of the topsides flowline shutdown valve to provide positive isolation from the well in accordance with SI 1029. The riser valve is reset locally and can be partially closed to 25% of its full travel for test purposes. The riser valves are controlled by the PSD System and are normally only closed on the occurrence of a Level C General Facilities Shutdown or in the event of Level A or B Emergency Shutdowns.


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Note: An Emergency Shutdown button is located in the CCR which 4.01 allows the riser PSD valves to be closed manually. Test and Production Manifolds (Continued) The riser valves are also closed on activation of the flowline High Integrity Protection System (HIPPS). This protection system is provided because the shut-in pressure of the Field pipelines may exceed the design pressure of the separation system vessels. The HIPPS System operates on a two-out-of-three voting system and is independent of the PSD System. Provision is made downstream of the riser valves to inject the following chemicals if required: 

Methanol: can be used to prevent hydrate formation during start-up/shutdown operations



Corrosion Inhibitor: can be used to prevent corrosion in the topsides pipework



Squeeze Chemicals: to chemically treat or ‘kill’ the well during well servicing operations

Isolation of the four oil production flowlines is provided downstream of the riser valves by the Flowline Shutdown Valves. All flowline valves are hydraulically actuated and controlled through the PSD System. The flowline valves are normally open but will close on the occurrence of a Level D Production Shutdown or in the event of a Level D General Facilities Shutdown or Level A or B Emergency Shutdowns. As with the riser valves, the flowline valves are also closed on activation of the flowline High Integrity Protection System (HIPPS). A Low Low Pressure Shutdown System is provided on each flowline upstream of the flowline valve utilising individual pressure transmitters. Activation of any of these instruments initiates a PSD to protect the Oil Processing Facilities from dangerously low pressures. Motorised choke valves are installed on all three Curlew production flowlines downstream of the flowline valves to control the flowrate of well fluids from the wells.


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Equipment Description 4.01 Test and Production Manifolds (Continued)

All choke valves are remotely operated from the PCS system. The position of the choke valve is accessed via the PCS system and a shutdown signal automatically closes the choke on the occurrence of a process shutdown or in the event of a Level C General Facilities Shutdown or Level A or B Emergency Shutdown. As the shut-in pressure of the Curlew Field pipelines and risers may exceed the design pressure of the separation vessels included in the Oil Processing Facilities, a High Integrity Protection System (HIPS) has been provided for each of the DP1 and 2 and Spare flowlines. Each comprises three independent pressure transmitters which operate in a two-out-of-three voting system. The BP1 flowline is equipped with two sets of three of HIPS transmitters. As with the other HIPS transmitters, each set comprises three independent pressure transmitters which operate in a two-out-of-three voting system. The HIPS facilities are located downstream of the topsides choke valves and operate independently of the PSD System. Provision is made downstream of the choke valves to inject Corrosion Inhibitor to prevent corrosion of the flowlines and downstream test and production manifolds. Temperature and pressure transmitters located upstream and downstream of the topsides choke valves continuously monitor the operating temperature and pressure of the oil flowlines in the swivel. Signals from each transmitter provides pressure/temperature indication on the PCS. Each indicator is equipped with high and low alarms which annunciate on the PCS. Manually operated diverter valves are positioned on the Curlew flowlines in the turret to direct the well fluids to the Test or Production Manifolds. Position indicators are provided for the diverter valves which relay the status of the each valve to the PCS. Opening or closing the correct sequence of spectacle blinds on the spare flowline allows the well fluids to be directed to the production, test or water injection swivel.


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Equipment Description 4.01 Test and Production Manifolds (Continued)

Note: A valve status interlock is provided for the topsides choke valve which prevents the choke from opening unless a permissive is obtained from the PCS. A permissive is only obtained if the position indicators for the diverter valves, flowline PSD valve and riser PSD valve indicate that a valid route is available to the test or production separation train. The production manifold for the Curlew BP1 well is 8in in diameter and is mounted around the base of the turret. During normal operation the production manifold for the Curlew D wells is 8in in diameter and located beneath the Curlew B manifold. The test manifold is positioned below the production manifolds and is 8in in diameter. The Curlew D manifold is provided with two nozzles, one for Riser DP1 and the other for DP2.

Cause and Effect Charts

The Cause and Effect Charts associated with the test and production manifolds are System 07, 27 and 34 CUR-MAS-PB-20655.

4.02 Test Separator V-1005 (Refer to P&ID Drg No CUR-MAS-PM-20048-501)

Curlew well fluids enter the Test separator through 10in pipework from the test manifold. Demulsifier and defoamer injection points are hardpiped to the Test separator inlet pipework to allow the injection of chemicals to improve the separation process. On entering the Test separator the flow of reservoir fluids is distributed throughout the vessel by a distribution plate fitted at the fluid inlet nozzle. This also reduces the velocity of the flow to aid separation. Separation takes place within the main hold-up area of the separator which contains two perforated baffle plates. The baffle plates are installed in a cross and longitudinal configuration and are designed to reduce the velocity of the reservoir fluids and minimise the effects of any surging. A corrugated plate coalescing pack assembly is fitted in between the two baffle plates to encourage coalescence and therefore enhance separation of the oil and water phases. Produced gas fills the vapour space of the vessel and the oil and produced water liquids collect on the bottom of the Test separator. The gas leaves the top of the separator through 10in gas outlet pipework after passing through a parallel plate vane mist eliminator which removes any liquids from the gas stream. The vane mist eliminator reduces the gas velocity and allows any entrained droplets to separate out by gravity, impinge on the parallel plates and fall back to the vessel. The eliminator is designed to ensure that the gas outlet stream contains a maximum of 0.1USgal/MMSCF and a maximum particle size of 10microns.


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Equipment Description 4.02 Test Separator V-1005 (Continued)

The flow of gas exiting the Test separator is metered by Vortex Meter 10FT-0515. This provides flow indication on PCS through Flow Indicator 10-FI-0515. A local sample point is situated adjacent to 10-FT-0515. This allows gas samples to be taken to determine the hydrocarbon composition of the Test separator off-gas. H 2 S scavenger is injected downstream of the sample point to ensure no build up of H 2 S in the system. Further details regarding chemical injection can be found in POPM Volume N41M3. Pressure within the Test separator is monitored through Pressure Transmitters 10-PT-0507, 10-PT-0508 and 10-PT-0509. Signals from 10PT-0507 are relayed to Pressure Controller 10-PIC-0507 which maintains the Test separator pressure. Signals from the other pressure transmitters provide input signals to the PSD system to protect the Test separator against high and low pressures. Pressure within the Test separator is controlled through Pressure Controller 10-PIC-0507. This controller operates on split range control and modulates Pressure Control Valves 10-PCV-0507A and B as required to maintain the control setpoint. Gas from the Test separator co-mingles with the gas outlet from the HP separator at the Inlet Cooler E-2201 in the Gas Compression Facilities under pressure control through 10-PCV-0507A for further processing. If the pressure in the Test separator rises and 10-PCV-0507A is fully open, then 10-PCV-0507B opens to control the pressure, directing the gas flow from the separator to the HP Flare System for safe disposal. The 10in gas outlet line contains Gas Outlet Shutdown Valve 20-XV-1191 located downstream of the Pressure Control Valve 10-PCV-0507A. This is a pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with open and closed position switches on the valve stem. These provide open and closed position indication on PCS through 20-ZI-1191. The valve is reset by the control room operator in the CCR after confirmation from the field operator that it is safe to do so. A contingency ‘wet’ fuel gas supply facility is provided from the gas outlet line of the Test separator to the Fuel Gas Cooler. This source of fuel gas is normally locked closed and is only used if the normal source of fuel gas from the glycol contactor is unavailable. The retention time of the liquids flowing through the Test separator is such that oil and water separation occurs in the bulk side of the vessel, with the less dense oil phase accumulating above the water layer.


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4.02 Test Separator V-1005 (Continued)

The interface level in the vessel is maintained by the Interface Level Control Valve 10-LCV-0511 located on the clean water outlet from the Test separator hydrocyclone. This level control valve is controlled by an Interface Level Controller 10-LIC-0511 on signals from Level Transmitter 10-LT-0511. The level controller is equipped with PCS generated high and low level alarms through 10-LAH-0511 and 10-LAL-0511 respectively. Alternatively, when the Curlew produced water rate is 5000BWPD and above, control signal 40-HS-4001A allows Test separator to be lined up with the HP Hydrocyclone. In this instance the interface level in the Test separator is maintained by Interface Control Valve 10-LCV-0111, located on the clean water outlet from the HP Hydrocyclone. This level control valve is controlled by an Interface Level Controller 10-LIC-0111 on signals from Level Transmitter 10-LT-0511. The level controller is equipped with PCS generated high and low level alarms through 10LAH-0511 and 10-LAL-0511 respectively. Level Transmitter 10-LT-0511 is located on top of the Test separator with its displacer located in a still well within the vessel to reduce motion effects. Produced water leaves the Test separator through 4in pipework containing Manual Isolation Valve HV-10281 to Test separator Hydrocyclone V-4003, or HP Hydrocyclone V-4001. The 4in produced water outlet pipework is insulated and heat traced for freeze protection. The flow of produced water to the Test Hydrocyclone, which is either from the Test separator or the HP Separator, is metered downstream of the shutdown valve by Vortex Meter 10-FT-0521. This provides produced water flow indication on PCS through 10-FI-0521. A chemical injection point is provided downstream of the vortex meter which can be utilised for the injection of scale inhibitors to prevent scaling of the produced water pipework or reverse demulsifiers to improve the performance of the Test separator hydrocyclone. Oil level in the Test separator is maintained by Level Control Valve 10-CV-0514 located on the oil outlet line from the vessel. This level control valve is controlled by Level Controller 10-LIC-0514 on signals from Level Transmitter 10-LT-0514. The level transmitter displacer is located in a still well within the vessel to reduce motion effects. The level controller is equipped with PCS generated high and low level alarms 10LAH-0514 and 10-LAL-0514 respectively. A normally isolated 3in bypass line is provided around the level control valve for use in the event of control valve maintenance.


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The Test separator is protected against high and low oil levels through Level Transmitters 10-LT-0512 and 10-LT-0513 respectively. Activation of either switch is relayed to the PSD System. Crude oil leaves the Test separator through 6in pipework to the MP Separator V-1002 or MP Heater E-1002 for further processing. The 6in oil outlet pipework contains Oil Outlet Shutdown Valve 10-XV0518. This is pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with open and closed position switches on the valve stem. These provide open and closed position indication on PCS through 10-ZI-0518. The oil outlet valve is reset by the control room operator in the CCR after confirmation from the field operator that it is safe to do so. A local sample point situated upstream of the shutdown valve enables crude oil samples to be obtained for analysis. The flow of crude oil from the Test separator is metered downstream of the shutdown valve by Vortex Meter 10-FT-0519. This provides oil outlet flow indication on PCS through 10-FI-0519. For future use the Test separator is provided with a sandwash facility This will be utilised to remove any deposited solids from the bottom of the separator by the introduction of seawater. A hose connection is fitted to the sandwash pipework to facilitate the transfer of deaerated seawater from the water injection or flushing water from the utility seawater system to the Test separator. When in use the sandwash water will be introduced to the Test separator through three high velocity jetting nozzles with the vessel on-line. Sandwash water will enter the base of the separator through individual valves fitted on the jetting lines. Any deposits from the bottom of the vessel will be directed to the skid drip pan through the belly drain lines for safe disposal to the Hazardous Open Drain. The following pressure and level trip signals are provided as inputs to the PSD system from transmitters on the Test separator: 10-LT-0510 10-LT-0512 10-LT-0513 10-PT-0508 10-PT-0509


Oil/Water Interface Level Low Low Oil Level Low Low Liquid Level High High Pressure Low Low Pressure High High

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Overpressure protection of the Test separator is provided by Pressure Safety Relief Valves, 10-PSV-0503A and 10-PSV-0503B, located on a line routed from the Test separator to the HP flare header. Both valves are set to relieve at 45.0barg and are fitted with a valve interlock system that ensures that one relief valve is on-line at all times. A normally isolated 1in line is provided around the PSV set which allows the Test separator to be manually depressurised to HP Flare. The Test separator may be automatically depressurised to HP Flare through 3in blowdown pipework containing Blowdown Valve 10-XV-0501. The blowdown valve is pneumatically actuated and fails open on loss of instrument air supply. The blowdown valve is controlled through the PSD system and is opened on activation of a Level C-Fire (C-F) - General Facilities Shutdown on Confirmed Fire. The rate of depressurisation is limited by Flow Orifice 10-FO-0502 installed downstream of the blowdown valve. The flow is restricted to ensure that the separator is depressurised within fifteen (15) minutes under fire conditions. The separator may also be manually depressurised through a 1in line upstream of the blowdown valve. This line is normally isolated and depressurises the separator to LP Flare.

Local Instrumentation

The following local instrumentation is provided on and around the Test separator: 10-LG-0517 10-LG-0516 10-TG-0505 10-TG-0528 10-PG-0506

Oil/Gas Interface Level Oil/Water Interface Level Vessel Temperature Produced water outlet temperature Vessel Pressure

Technical Data

Dimensions: Design Pressure: Design Temperature:

Cause and Effects

The Cause and Effect Chart associated with the Test separator is System 10.2 CUR-MAS-PB-20655.


2200mm ID x 4900mm TT Full Vac/45barg -30°C/+100°C

Page 10 / 36



4.03 HP Separator V-1001 (Refer to P&ID Drg No CUR-MAS-PM-20041-501)

Reservoir fluids from the Curlew production wells enter the HP separator through 14in pipework from the turret swivel. Demulsifier and defoamer injection points are hardpiped to the HP separator inlet pipework allowing the injection of chemicals to improve the separation process. On entering the HP separator the flow of reservoir fluids is distributed throughout the vessel by a distribution plate fitted at the fluid inlet nozzle. This also reduces the velocity of the flow to aid separation. Separation takes place within the main hold-up area of the separator which contains four perforated baffle plates. The baffle plates are installed in a cross and longitudinal configuration and are designed to reduce the velocity of the reservoir fluids and minimise the effects of any surging. A corrugated plate coalescing pack assembly is installed downstream of the perforated baffle plates to encourage coalescence and therefore enhance separation of the oil and water phases. Produced gas fills the vapour space of the vessel and the oil and produced water liquids collect on the bottom of the HP separator. The separated gas flow leaves the separator through 12in pipework after passing through a parallel plate vane mist eliminator which removes any entrained liquids from the gas stream. The vane mist eliminator reduces the gas velocity and allows any entrained droplets to separate out by gravity, impinge on the parallel plates and fall back to the vessel. The eliminator is designed to ensure that the gas outlet stream contains a maximum of 0.1USgal/MMSCF and a maximum particle size of 10microns. The flow of gas exiting the HP separator is metered by Vortex Meter 10FT-0115. This provides flow indication on PCS through Flow Indicator 10-FI-0115. A local sample point is situated adjacent to 10-FT-0115. This allows gas samples to be obtained to determine the hydrocarbon composition of the HP separator off-gas. H 2 S scavenger is injected downstream of the sample point to ensure no build up of H 2 S in the system. Further details regarding chemical injection can be found in POPM Volume N41M3. Pressure within the HP separator is monitored through Pressure Transmitters 10-PT-0107. 10-PT-0108 and 10-PT-0109. Signals from 10PT-0107 are relayed to Pressure Controller 10-PIC-0107 which vents excess pressure from the HP separator to HP Flare through Pressure Control Valve 10-PCV-0107. Signals from the other pressure transmitters provide input signals to the PSD system to protect the HP separator against high and low pressures.


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4.03 HP Separator V-1001 (Continued)

Pressure within the HP separator is normally controlled by the load control setpoint for Export Compressor K-2001. Gas is routed from the top of the HP separator through 10in pipework and normally passes to the Inlet Cooler E-2201 through Inlet Cooler Gas Supply Valve 22-XV-1051. This is a pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with switches on the valve stem. These provide open and closed position indication on PCS through 22-ZI-1051. The inlet cooler is provided with a 2in pressurisation bypass line containing Pressurisation Valve 22-XV-1052. This is a pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with position switches on the valve stem. These provide open and closed position indication on PCS through 22-ZI-1052. The valves are reset by the control room operator in the CCR after confirmation from the field operator that it is safe to do so. A contingency supply of ‘wet’ fuel gas supply is provided from the gas outlet line of the HP separator to the fuel gas cooler. This source of fuel gas is normally isolated and is only in use if the normal source of fuel gas from the glycol contactor is unavailable. The retention time of the liquids flowing through the HP separator is such that oil and water separation occurs in the bulk side of the vessel, with the less dense oil phase accumulating above the water layer. The interface level in the vessel is maintained by the Interface Level Control Valve 10-LCV-0111 located on the clean water outlet from the HP separator hydrocyclone. This level control valve is controlled by an Interface Level Controller 10-LIC-0111 on signals from Level Transmitter 10-LT-0111. The level controller is equipped with PCS generated high and low level alarms through 10-LAH-0111 and 10-LAL-0111 respectively. Alternatively when the Curlew produced water rate is 5000BWPD and above, control signal switch 40-HS-4001A allows HP Separator to be lined up with the Test Hydrocyclone. In this instance the interface level in the HP Separator is maintained by Interface Level Control Valve 10-LCV0511, located on the clean water outlet from the Test Hydrocyclone. This level control valve is controlled by an Interface Level Controller 10-LIC0511 on signals from Level Transmitter 10-LT-0111. The level controller is equipped with PCS generated high and low level alarms through 10LAH-0111 and 10-LAL-0111 respectively.


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Equipment Description 4.03 HP Separator V-1001 (Continued)

Level Transmitter 10-LT-0111 is located on top of the HP separator with its displacer located in a still well within the vessel to reduce motion effects. Produced water leaves the HP separator through 6in pipework containing Manual Isolation Valve HV-10046 to HP Hydrocyclone V-4001, or Test Hydrocyclone V-4003. The 6in produced water outlet pipework is insulated and heat traced for freeze protection. The flow of produced water to the HP Hydrocyclone, which is either from the HP Separator or the Test separator, is metered downstream of the outlet valve HV-10046 by Vortex Meter 10-FT-0121. This provides flow indication on PCS through Flow Indicator 10-FI-0121. A chemical injection point is provided downstream of the vortex meter which can be utilised for the injection of scale inhibitors to prevent scaling of the produced water pipework or reverse demulsifiers to improve the performance of the HP separator hydrocyclone. Oil level in the HP separator is maintained by Level Control Valve 10-LCV-0114 located on the oil outlet line from the HP crude oil heater. This level control valve is controlled by Level Controller 10-LIC-0114 on signals from Level Transmitter 10-LT-0114. The level transmitter displacer is located in a still well within the vessel to reduce motion effects. The level controller is equipped with PCS generated high and low level alarms 10-LAH-0114 and 10-LAL-0114 respectively. Crude oil leaves the HP separator through 6in pipework to the HP Crude Oil Heater E-1001 for further processing. The 6in crude oil outlet pipework contains Oil Outlet Shutdown Valve 10XV-0118. This is a pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with open and closed position switches on the valve stem. These provide open and closed position indication on PCS through 10-ZI-0118. The oil outlet valve is reset from the control room after confirmation from the field that it is safe to do so. A local sample point situated upstream of the shutdown valve enables crude samples to be taken for analysis. The flow of crude oil from the HP separator is metered downstream of the shutdown valve by Vortex Meter 10-FT-0119. This provides flow indication on PCS through Flow indicator 10-FI-0119.


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Equipment Description 4.03 HP Separator V-1001 (Continued)

For future use the HP separator is provided with a sandwash facility which will be utilised to remove any deposited solids from the bottom of the separator by the introduction of seawater. A hose connection is fitted to the sandwash pipework to facilitate the transfer of deaerated seawater from the water injection or flushing water from the utility seawater system to the HP separator. When in use the sandwash water will be introduced to the HP separator through three high velocity jetting nozzles with the vessel on-line. Sandwash water will enter the base of the separator through individual valves fitted on the jetting lines. Any deposits from the bottom of the vessel will be directed to the skid drip pan through the belly drain lines for safe disposal to the Hazardous Open Drain. The following pressure and level trip signals are provided as inputs to the PSD system from transmitters on the vessel: 10-LT-0110 10-LT-0112 10-LT-0113 10-PT-0108 10-PT-0109


Overpressure protection of the HP separator is provided by Pressure Safety Relief Valves, 10-PSV-0103A and 10-PSV-0103B located on a line routed from the HP separator to the HP flare header. Both valves are set to relieve at 45.0barg and are fitted with a valve interlock system that ensures that one relief valve is on-line at all times. A normally isolated 1in line is provided around the PSV set which allows the HP separator to be manually depressurised to HP Flare. The HP separator may be automatically depressurised to HP Flare through 4in blowdown pipework containing Blowdown Valve 10-XV-0101. The blowdown valve is pneumatically actuated and fails open on loss of instrument air supply. The blowdown valve is controlled through the PSD system and is opened on activation of a Level C-Fire (C-F) - General Facilities Shutdown on Confirmed Fire. The rate of depressurisation is limited by Flow Orifice 10-FO-0102 installed downstream of the blowdown valve. The flow is restricted to ensure that the separator is depressurised within fifteen (15) minutes under fire conditions. The separator may also be manually depressurised through a 1in line upstream of the blowdown valve. This line is normally isolated and depressurises the separator to LP Flare.


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Equipment Description 4.03 HP Separator V-1001 (Continued) Local Instrumentation

The following local instrumentation is provided on and around the HP Separator: 10-LG-0117 10-LG-0116 10-TG-0105 10-PG-0106

Oil/Gas Interface Level Oil/Water Interface Level Vessel Temperature Vessel Pressure

Technical Data


Cause and Effects

The Cause and Effect Chart associated with the HP separator is System 10.1 CUR-MAS-PB-20655.

4.04 HP Crude Oil Heater E-1001 (Refer to P&ID Drg CURMAS-PM-20042-501)

2900mm ID x 7000mm TT Full Vac/45barg -30°C/+100°C

Partially stabilised crude oil from the HP separator flows through a manual isolation valve to the HP crude oil heater inlet. The HP crude oil heater is a horizontally mounted shell and tube heat exchanger located in the HP separation train. Crude oil is passed through the tube bundle of the exchanger where it is heated to between 55 and 75oC by heat exchange with the heating medium flowing through the shellside. The heated crude leaves the exchanger through a 6in connection fitted to the tube head and passes on to the MP separator for further stabilising. The flow of crude oil through the exchanger is controlled through Level Control Valve 10-LCV-0114 located on the oil outlet line. The control valve controls the oil level in the HP separator on signals from Level Controller 10-LIC-0114. The level control valve is pneumatically operated and fails closed on loss of instrument air supply. A normally isolated 3in bypass line is provided around the level control valve for use in the event of control valve maintenance. The 30% TEG/70% freshwater solution utilised for heating purposes flows through a 4in supply line from the heating medium circuit to the shellside of the HP crude oil heater. The heating medium then passes through the exchanger where heat is exchanged with the crude oil passing through the tubeside of the unit. After giving up its heat to the crude oil, the heating medium passes out of the exchanger through Temperature Control Valve 10-TCV-0155 and downstream Shutdown Valve 44-XV-2017 before flowing to the heating medium return circuit.


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Equipment Description 4.04 HP Crude Oil Heater E-1001 (Continued)

The shutdown valve is a pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD system and is equipped with position switches on the valve stem. These provide open and closed indication on PCS through 44-ZI-2017. The valve is reset by the control room operator in the CCR after confirmation from the field operator that it is safe to do so. Heating medium flow through the exchanger is controlled by Temperature Control Valve 10-TCV-0155. This temperature control valve is regulated by Temperature Controller 10-TIC-0155 on signals from Temperature Transmitter 10-TT-0155 located on the heater oil outlet line. The temperature controller is equipped with PCS generated high and low temperature alarms through 10-TAH-0155 and 10-TAL-0155 respectively. The following temperature and pressure trip signals are provided as inputs to the PSD System from transmitters located on the crude oil and heating medium outlets from the heater: 10-TT-0154 44-PT-2016

Crude oil outlet temperature high high Heating Medium outlet pressure high high

In the unlikely event of tube bundle rupture, the heating medium circuit is protected from overpressurisation by Pressure Transmitter 44-PT-2016 fitted to the heating medium outlet from the HP crude oil heater. Activation of 44-PT-2016 initiates a PSD shutdown which isolates the flowrate of crude through the heater. Overpressure protection of the tubeside of the HP crude oil heater is provided by Pressure Safety Valve 10-PSV-0153 located on the oil outlet line. This relief valve is set at 45barg and relieves excess pressure to the HP Flare header. Overpressure protection of the shellside of the HP crude oil heater is provided by Pressure Safety Valve 44-PSV-2013 located on the heating medium outlet line. This relief valve is set at 16barg and relieves excess pressure to the LP Flare. Local Instrumentation

The following local instrumentation is provided on and around the HP crude oil heater: 10-TG-0151 10-TG-0156 10-PG-0157 44-TG-2011 44-PG-2012 44-TG-2015 44-PG-2014


Crude oil to E-1001 temperature Crude oil from E-1001 temperature Crude oil from E-1001 pressure Heating Medium to E-1001 temperature (at heating medium circuit) Heating Medium to E-1001 pressure (at heating medium circuit) Heating medium from E-1001 temperature (at heating medium circuit) Heating medium from E-1001 pressure (at heating medium circuit)

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4.04 HP Crude Oil Heater E-1001 (Continued)

Technical Data

Dimensions: Design Pressure (oil side): Design (heating medium side): Design Temperature (oil side): Design (heating medium side): Design Duty:

4500mm TT 45barg Pressure 16barg -30oC to 120oC Temperature 130oC 1509KW

Cause and Effects

The Cause and Effect Chart associated with the HP crude oil heater is System 10.1 CUR-MAS-PB-20655.

4.05 MP Separator V-1002 (Refer to P&ID Drg No CUR-MAS-PM-20043-001)

Reservoir fluids from the Curlew B Production Well BP1 enter the MP separator through 10in pipework from the turret swivel. Demulsifier and defoamer injection points are hardpiped to the MP separator inlet header for dosing with chemicals to improve the separation process. Fluids from the following sources are also directed to the MP separator inlet header: 

Pre-heated crude oil from the HP Crude Oil Heater E-1001



Curlew crude oil from the Test separator V-1005



Produced water from the common discharge of the Produced Water Pumps P-1002A/B



Condensates recovered from the Export Gas Scrubber V-2001 and Glycol Contactor C-2201

On entering the MP separator the flow of reservoir fluids is distributed throughout the vessel by a distribution plate fitted at the fluid inlet nozzle. This also reduces the velocity of the flow to aid separation. Separation takes place within the main hold-up area of the separator which contains four perforated baffle plates. The baffle plates are installed in a cross and longitudinal configuration and are designed to reduce the velocity of the reservoir fluids and minimise the effects of any surging. A corrugated plate coalescing pack assembly is installed downstream of the perforated baffle plates to encourage coalescence and therefore enhance separation of the oil and water phases.


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Equipment Description 4.05 MP Separator V-1002 (Continued)

Produced gas fills the vapour space of the vessel and the oil and produced water liquids collect on the bottom of the MP separator. The separated gas flow leaves the separator through 10in pipework after passing through a parallel plate vane mist eliminator which removes any entrained liquids from the gas stream. The vane mist eliminator reduces the gas velocity and allows any entrained droplets to separate out by gravity, impinge on the parallel plates and fall back to the vessel. The eliminator is designed to ensure that the gas outlet stream contains a maximum of 0.1USgal/MMSCF. The flow of gas exiting the MP separator is metered by Vortex Meter 10FT-0215. This provides flow indication on PCS through Flow Indicator 10-FI-0215. A local sample point is situated adjacent to 10-FT-0215. This allows gas samples to be obtained to determine the hydrocarbon composition of the MP separator off-gas. Pressure within the MP separator is monitored through Pressure Transmitters 10-PT-0207. 10-PT-0208 and 10-PT-0209. Signals from 10PT-0207 are relayed to Pressure Controller 10-PIC-0207 which vents excess pressure from the MP separator to HP Flare through Pressure Control Valve 10-PCV-0207B. Signals from the other pressure transmitters provide input signals to the PSD system to protect the MP separator against high and low pressures. Pressure Control Valve 10-PCV-0207B is a pneumatically operated valve which fails closed on loss of instrument air supply. Pressure within the MP separator is normally controlled by the load control setpoint for MP Compressor K-2002. Gas is routed from the top of the MP separator through 10in pipework and passes to the MP Compressor Suction Cooler E-2002 through MP Compressor Suction Cooler Gas Supply Valve 20-XV-1201. This is a pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with switches on the valve stem. These provide open and closed position indication on PCS through 20-ZI-1201. The MP compressor suction cooler is provided with a 2in pressurisation bypass line containing Pressurisation Valve 20-XV-1202.


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This is a pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with position switches on the valve stem. These provide open and closed position indication on PCS through 20-ZI-1202. The valves are reset by the control room operator in the CCR after confirmation from the field operator that it is safe to do so. The retention time of the liquids flowing through the MP separator is such that oil and water separation occurs in the bulk side of the vessel, with the less dense oil phase accumulating above the water layer. The interface level in the vessel is maintained by the Interface Level Control Valve 10-LCV-0211 located on the clean water outlet from MP Hydrocyclone V-4002. This level control valve is controlled by an Interface Level Controller 10LIC-0211 on signals from Level Transmitter 10-LT-0211. The level controller is equipped with PCS generated high and low level alarms through 10-LAH-0211 and 10-LAL-0211. Level Transmitter 10-LT-0211 is located on top of the MP separator with its displacer located in a still well within the vessel to reduce motion effects. Produced water leaves the vessel through 6in pipework containing Manual Isolation Valve HV-10112 to MP Hydrocyclone V-4002. The 6in produced water outlet pipework is insulated and heat traced for freeze protection. The flow of produced water from the MP separator is metered downstream of HV-10112 by Vortex Meter 10-FT-0221. This provides flow indication on PCS through Flow Indicator 10-FI-0221. Oil level in the MP separator is maintained by Level Control Valve 10-LCV-0214 located on the 8in crude oil outlet line. This level control valve is controlled by Level Controller 10-LIC-0214 on signals from Level Transmitter 10-LT-0214. The level transmitter displacer is located in a still well within the vessel to reduce motion effects. The level controller is equipped with PCS generated high and low level alarms 10-LAH-0214 and 10-LAL-0214 respectively. Crude oil leaves the MP separator through 8in pipework to the MP Crude Oil Heater E-1002 for further processing. The 8in crude oil outlet pipework contains Oil Outlet Shutdown Valve 10XV-0218. This is pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with open and closed position switches on the valve stem. These provide open and closed position indication on PCS through 10-ZI-0218.


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The oil outlet valve is reset from the control room after confirmation from the field that it is safe to do so.

A local sample point situated upstream of the shutdown valve enables a crude samples to be taken for analysis. The flow of crude oil from the MP separator is metered downstream of the shutdown valve by Vortex Meter 10-FT-0219. This provides flow indication on PCS through Flow indicator 10-FI-0219. For future use the MP separator is provided with a sandwash facility This will be utilised to remove any deposited solids from the bottom of the separator by the introduction of seawater. A hose connection is fitted to the sandwash pipework to facilitate the transfer of deaerated seawater from the water injection or flushing water from the utility seawater system to the MP separator. When in use the sandwash water will be introduced to the MP separator through five high velocity jetting nozzles with the vessel on-line. Sandwash water will enter the base of the separator through individual valves fitted on the jetting lines. Any deposits from the bottom of the vessel will be directed to the skid drip pan through the belly drain lines for safe disposal to the Hazardous Open Drain. The following pressure and level trip signals are provided as inputs to the PSD system from transmitters on the vessel: 10-LT-0210 10-LT-0212 10-LT-0213 10-PT-0208 10-PT-0209


Overpressure protection of the MP separator is provided by Pressure Safety Relief Valves, 10-PSV-0203A and 10-PSV-0203B located on a line routed from the MP separator to the LP flare header. Both valves are set to relieve at 16.0barg and are fitted with a valve interlock system that ensures that one relief valve is on-line at all times. A normally isolated 1in line is provided around the PSV set which allows the MP separator to be manually depressurised to LP Flare. The MP separator may be automatically depressurised to LP Flare through 4in blowdown pipework containing Blowdown Valve 10-XV-0201. The blowdown valve is pneumatically actuated and fails open on loss of instrument air supply. The blowdown valve is controlled through the PSD system and is opened on activation of a Level C-Fire (C-F) - General Facilities Shutdown on Confirmed Fire.


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The rate of depressurisation is limited by Flow Orifice 10-FO-0202 installed downstream of the blowdown valve. The flow is restricted to ensure that the separator is depressurised within fifteen (15) minutes under fire conditions.


The following local instrumentation is provided on and around the MP Separator: 10-LG-0217 10-LG-0216 10-TG-0205 10-PG-0206


Technical Data


Cause and Effects

The Cause and Effect Chart associated with the MP separator is System 10.1 CUR-MAS-PB-20655.


3200mm ID x 7200mm TT 16barg -30oC/+100oC

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4.06 MP Crude Oil Heater E-1002 (Refer to P&ID Drg No CUR-MAS-PM-20044-501)

Partially stabilised crude from the oil outlet line of the MP separator flows through 8in pipework which increases to a 16in line downstream of Level Control Valve 10-LCV-0214. The crude oil stream is then routed to the inlet of the MP crude oil heater. Fluids from the following sources are also directed to the inlet header for the MP crude oil heater: 

Curlew crude oil from Test separator V-1005



Produced water from Electrostatic Coalescer V-1004



Condensate recovered from the LP and MP Compressor Suction Scrubbers



Condensate recovered from the Fuel Gas Scrubber V-5201 and Glycol Regeneration Package A-2201



Liquids from the LP and HP Flare KO drums

A manually operated isolation ball valve is provided on the process inlet to the MP crude oil heater. This valve is always in the open position as the MP crude oil heater is in continuous service. Crude oil passes through the MP crude oil heater where the temperature of the oil is increased to 65 to 68oC by heat exchange with heating medium. The heated oil flows out of the plate type exchanger and combines with the reject oil flow from the HP, MP and Test Hydrocyclones before passing onwards to the LP separator for full stabilisation. The 30% TEG/70% freshwater solution utilised for heating purposes flows through a 6in supply line to the hot side of the MP crude oil heater from the heating medium circuit. The heating medium passes through the plate type exchanger where heat is exchanged with the crude. After giving its heat to the crude oil, the heating medium passes out of the MP crude heater through 6in pipework containing Temperature Control Valve 10-TCV-0255. The temperature control valve is a pneumatically operated valve which fails closed on loss of instrument air supply. The valve is provided with a normally isolated 4in bypass line for use in the event of control valve maintenance.


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4.06 MP Crude Oil Heater E-1002 (Continued)

Heating medium flow through the MP crude oil heater is controlled by Temperature Control Valve 10-TCV-0255. This temperature control valve is regulated by Temperature Controller 10-TIC-0255 on signals from Temperature Transmitter 10-TT-0255 located on the heater oil outlet line. The temperature controller is equipped with PCS generated high and low temperature alarms through 10-TAH-0255 and 10-TAL-0255 respectively. The following temperature trip signal is provided as an input to the PSD System from an independent transmitter located on the oil outlet from the MP crude oil heater: 21-TT-0254

Crude oil temperature high high

Overpressure protection of the crude oil side of the MP crude oil heater is provided by a Pressure Safety Relief Valve 10-PSV-0253 located on the oil inlet line. This relief valve is set at 16barg and relieves excess pressure to the LP flare header. Local Instrumentation

The following local pressure and temperature instrumentation is provided on and around the MP crude oil heater: 10-TG-0251 10-PG-0250 10-TG-0256 10-PG-0257 44-TG-2021 44-PG-2022 44-TG-2025 44-PG-2024

Technical Data

Crude oil to E-1002 temperature Crude oil to E-1002 pressure Crude oil from E-1002 temperature Crude oil from E-1002 pressure Heating medium to E-1002 temperature Heating medium to E-1002 pressure Heating medium from E-1002 temperature Heating medium from E-1002 pressure

Overall Dimensions: Design Pressure (Oil Side): Design (Heating Medium Side): Design Temperature (Oil Side): Design (Heating Medium Side): Duty:

Cause and Effects

1828m (L) x 1060mm (W) x 1985mm (H) 16.0barg Pressure 16.0barg -30oC to 120oC Temperature 130oC 6288KW

The Cause and Effect Chart associated with the heater is System 10-1 CUR-MAS-PB-20655.


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4.07 LP Separator V-1003 (Refer to P&ID Drg No CUR-MAS-PM-20045-001)

Pre-heated crude enters the LP separator through 20in pipework from the MP crude oil heater. On entering the vessel the crude oil flow is distributed throughout the vessel by a distribution plate fitted at the fluid inlet nozzle. This also reduces the velocity of the flow to aid separation. Separation takes place within the main hold-up area of the separator which contains four perforated baffle plates. The baffle plates are installed in a cross and longitudinal configuration and are designed to reduce the velocity of the reservoir fluids and minimise the effects of any surging. A corrugated plate coalescing pack assembly is installed downstream of the perforated baffle plates to encourage coalescence and therefore enhance separation of the oil and water phases. Produced gas fills the vapour space of the vessel and the oil and produced water liquids collect on the bottom of the LP separator. The separated gas leaves the separator through 16in pipework after passing through a parallel plate vane mist eliminator which removes any entrained liquids from the gas stream. The vane mist eliminator reduces the gas velocity and allows any entrained droplets to separate out by gravity, impinge on the parallel plates and fall back to the vessel. The eliminator is designed to ensure that the gas outlet stream contains a maximum of 0.1USgal/MMSCF and a maximum particle size of 10microns. The flow of gas exiting the LP separator is metered by Vortex Meter 10FT-0315. This provides flow indication on PCS through Flow Indicator 10-FI-0315. A local sample point is situated adjacent to 10-FT-0315. This allows gas samples to be obtained to determine the hydrocarbon composition of the LP separator off-gas. Pressure within the LP separator is monitored through Pressure Transmitters 10-PT-0307. 10-PT-0308 and 10-PT-0309. Signals from 10-PT-0307 are relayed to Pressure Controller 10-PIC-0307 which vents excess pressure from the LP separator to LP Flare through Pressure Control Valve 10-PCV-0307B. This pressure controller is equipped with PCS generated high and low pressure alarms through 10PAH-0307 and 10-PAL-0307 respectively. The controller also provides an input signal to True Vapour Pressure (TVP) Relay 10-XY-0307.


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4.07 LP Separator V-1003 (Continued)

Signals from the other pressure transmitters provide input signals to the PSD system to protect the LP separator against high and low pressures.

Pressure Control Valve 10-PCV-0307B is a pneumatically operated valve which fails closed on loss of instrument air supply. Pressure within the LP separator is normally controlled by the load control setpoint for LP Compressor K-2003. Gas is routed from the top of the LP separator to the inlet of LP Compressor Cooler E-2003 through 16in pipework containing Shutdown Valve 20-XV-1221. This is a pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with position switches on the valve stem. These provide open and closed position indication on PCS through 20-ZI-1221. The shutdown valve is reset by the control room operator from the CCR after confirmation from the field that it is safe to do so. The retention time of the liquids flowing through the LP separator is such that oil and water separation occurs in the bulk side of the vessel, with the less dense oil phase accumulating above the water layer. The interface level in the LP separator is maintained by the Interface Level Controller 10-LIC-0311 on signals from Level Transmitter 10LT-0311. The level controller operates in an on/off control configuration and controls the interface level by starting and stopping the duty Produced Water Transfer Pump P-1002A/B located beneath the vessel. The level controller is equipped with high and low level alarms which on activation annunciate on PCS through 10-LAH-0311 and 10-LAL-0311 respectively. Level Transmitter 10-LT-0311 is located on top of the LP separator with its displacer located in a still well within the vessel to reduce motion effects. Produced water leaves the LP separator through 3in pipework and is routed to the suction of Produced Water Transfer Pumps P-1002A/B. These facilities return the produced water from the LP separator to the MP separator and are detailed in Paragraph 4.08 of this Volume.


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The 3in produced water outlet pipework is insulated and heat traced for freeze protection and contains Produced Water Outlet Valve 10-XV0334. This is a pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with position switches on the valve stem. These provide open and closed indication on PCS through 10-ZI-0334. The produced water outlet valve is reset from the control room after confirmation from the field that it is safe to do so. The flow of produced water from the LP separator is metered downstream of the produced water transfer pumps by Vortex Meter 10FT-0321. This provides flow indication on PCS through Flow Indicator 10-FI-0321. Oil level in the LP separator is maintained by Level Control Valve 10-LCV-0314 located on the oil outlet line from the Export Crude Oil Cooler E-1004. This level control valve is controlled by Level Controller 10-LIC-0314 on signals from Level Transmitter 10-LT-0314. The level transmitter displacer is located in a still well within the vessel to reduce motion effects. The level controller is equipped with PCS generated high and low level alarms 10-LAH-0314 and 10-LAL-0314 respectively. Crude oil leaves the LP separator through 12in pipework to the suction of Crude Oil Transfer Pumps P-1001A/B. These facilities direct the crude recovered in the LP separator to the Electrostatic Coalescer V-1004 for further processing. Full details on the operation and control of the crude oil transfer pumps are provided in Paragraph 4.09 of this Volume. The 12in crude oil outlet pipework contains Oil Outlet Shutdown Valve 10-XV-0335. This is pneumatically actuated valve which fails closed on loss of instrument air supply. The valve is controlled through the PSD System and is equipped with open and closed position switches on the valve stem. These provide open and closed position indication on PCS through 10-ZI-0335. The oil outlet valve is reset from the control room after confirmation from the field that it is safe to do so. A local sample point situated downstream of the shutdown valve enables crude samples to be taken for analysis. For future use the LP separator is provided with a sandwash facility This will be utilised to remove any deposited solids from the bottom of the separator by the introduction of seawater. A hose connection is fitted to the sandwash pipework to facilitate the transfer of deaerated seawater from the water injection or flushing water from the utility seawater system to the LP separator.


Page 26 / 36




When in use the sandwash water will be introduced to the LP separator through five high velocity jetting nozzles with the vessel on-line. Sandwash water will enter the base of the separator through individual valves fitted on the jetting lines. Any deposits from the bottom of the vessel will be directed to the skid drip pan through the belly drain lines for safe disposal to the Hazardous Open Drain. The following pressure and level trip signals are provided as inputs to the PSD system from transmitters on the vessel: 10-LT-0310 10-LT-0312 10-LT-0313 10-PT-0308 10-PT-0309


Overpressure protection of the LP separator is provided by Pressure Safety Relief Valves, 10-PSV-0303A and 10-PSV-0303B. These relief valves are set at 16barg and relieve excess pressure to the LP flare header. The PSV sets are fitted with a valve interlock system which ensures that one of the relief valves is on-line at all times. A normally isolated 1in line is provided around the PSV set which allows the LP separator to be manually depressurised to LP Flare. The LP separator may be automatically depressurised to LP Flare through 4in blowdown pipework containing Blowdown Valve 10-XV-0301. The blowdown valve is pneumatically actuated and fails open on loss of instrument air supply. The blowdown valve is controlled through the PSD system and is opened on activation of a Level C-Fire (C-F) - General Facilities Shutdown on Confirmed Fire. The rate of depressurisation is limited by Flow Orifice 10-FO-0302 installed downstream of the blowdown valve. The flow is restricted to ensure that the separator is depressurised within fifteen (15) minutes under fire conditions. Local Instrumentation

The following local instrumentation is provided on and around the LP Separator: 10-LG-0317 10-LG-0316 10-TG-0305 10-PG-0306



Page 27 / 36



Technical Data


Cause and Effects

The Cause and Effect Chart associated with the LP separator is System 10.2 CUR-MAS-PB-20655.


2900mm ID x 6650mm TT Full Vac/16barg -30oC/+85oC

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4.08 Produced Water Transfer Pumps P-1002A/B (Refer to P&ID Drg No CUR-MAS-PM-20045-501)

Produced water is routed from the LP separator to the individual suction lines for the produced water transfer pumps through 3in pipework containing Produced Water Outlet Shutdown Valve 10-XV-0334. Both suction lines are fitted with a manual isolation valve and a downstream strainer. The in-line strainer is provided to remove any material from the produced water stream which could damage the pump internals. The transfer pumps and associated suction and discharge pipework is insulated and heat traced for freeze protection. The suction pressure available at the produced water transfer pump is a combination of LP separator pressure and positional head and is in order of 1.1barg. An allowance has been made to compensate for spurious reductions in static head due to vessel motion to ensure that the minimum suction pressure for safe operation of the duty produced water transfer pump is always maintained. The produced water transfer pumps are electric single stage centrifugal pumps manufactured by Howmar. The function of the duty pumps is to increase the pressure of the produced water recovered from the LP separator to around 11barg. This provides the necessary pressure to direct a 16.5m3/hr flowrate of produced water back to MP Separator V1002. The produced water transfer pumps are rated for 100% duty and operate on a duty/standby basis. The water return pumps are driven by 18.5KW motors through direct flanged couplings. The pumps are controlled remotely via the Interface Level Controller 10-LIC-0311 for the LP separator but can be shutdown locally through individual emergency stop pushbuttons provided at the pump skids. PSD inputs to the produced water transfer pump control system provide remote pump shutdowns in the event of an emergency. Note: Before the duty produced water transfer pump can be remotely controlled from the PCS the pump must be set for ‘Remote Operation’ in the MAERSK FPSOS HEADQUARTERS. Produced water leaves the discharge nozzle of each pump through 2in pipework to the common discharge header and back to the MP separator. Each discharge line is fitted with a non-return valve to prevent reverse flow and a manually operated block valve to facilitate pump isolation. Minimum flow protection for the duty produced water transfer pump is provided by recycling produced water from the common discharge through a 2in minimum flow bypass line back to the LP separator.


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4.08 Produced Water Transfer Pumps P-1002A/B (Continued)

The produced water discharge flowrate is monitored through Vortex Meter 10-FT-0321 installed in the common discharge header from the produced water transfer pumps. This provides flow indication on PCS through Flow Indicator 10-FI-0321. Signals from 10-FT-0321 are relayed to Produced Water Transfer Pump Minimum Flow Controller 10-FIC0321. This controller modulates Flow Control Valve 10-FCV-0321 located in the 2in minimum flow bypass line.


The following local instrumentation is provided on and around the produced water transfer pumps: 10-PG-0326 10-PG-0327

P-1002A Discharge Pressure P-1002B Discharge Pressure 16.5m3/hr 12barg 11barg 18.5KW per pump

Technical Data

Design Capacity: Design Pressure: Discharge Pressure: Power Installed:

Cause and Effects

The Cause and Effect Chart associated with the Produced Water Transfer Pumps are the same as those for the LP separator and are detailed on System 10.2 CUR-MAS-PB-20655.


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4.09 Crude Oil Transfer Pumps P-1001A/B (Refer to P&ID Drg No CUR-MAS-PM-20045-001)

Fully stabilised crude oil is routed from the LP separator to the individual suction lines for the crude oil transfer pumps through 12in pipework containing Oil Outlet Shutdown Valve 10-XV-0335. Both suction lines are fitted with a manual isolation block valve and downstream strainer. The in-line strainer is provided to remove any material from the crude oil which could damage the pump internals. The suction pressure available at the pump is a combination of LP separator pressure and positional head and is in the order of 1.1barg under normal conditions. An allowance has been made to compensate for spurious reductions in static head due to vessel motion to ensure that the minimum suction pressure for the duty crude oil transfer pump is always maintained. The crude oil transfer pumps are electric single stage centrifugal pumps manufactured by Howmar. The function of the duty crude oil transfer pump is to increase the pressure of the crude recovered from the LP separator to around 7barg. The duty crude oil transfer pump provides the necessary pressure to direct 326m3/hr crude to the Electrostatic Coalescer V-1004 for further processing. The crude oil transfer pumps are rated for 100% duty and operate on a duty/standby basis. The crude oil transfer pumps are driven by 90 KW motors through direct flanged couplings. The pumps are started and stopped remotely from the CCR but can be shutdown locally through individual emergency stop pushbuttons 10-HS-0324 and 10-HS-0325 at Crude Oil Transfer Pumps P-1001A and B respectively. PSD inputs to the crude oil transfer pump control system provide remote pump shutdowns in the event of an emergency. Crude oil leaves the discharge nozzle of each pump through 8in discharge pipework and forms a common discharge header. Oil is then routed from the discharge header to the electrostatic coalescer. Each pump discharge line is fitted with a non-return valve to prevent reverse flow and a manually operated block valve to facilitate pump isolation. Minimum flow protection for the duty crude oil transfer pump is provided by recycling crude from the common discharge through a 4in minimum flowline back to the LP separator. The discharge flow from the crude oil pumps is monitored through Flow Transmitter 10-FT-0328. Signals from the flow transmitter are relayed to Crude Oil Transfer Pump Minimum Flow Controller 10-FIC-0328. This controller modulates Flow Control Valve 10-FCV-0328 located in the 4in minimum flow pipework. The minimum flow controller is normally set in auto control mode with the setpoint adjusted to provide adequate pump protection against low flow to prevent cavitation.


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4.09 Crude Oil Transfer Pumps P-1001A/B (Continued) 326m3/hr 1.7Metres 92.3Metres 90KW per pump

Technical Data

Design Capacity: NPSH: Head: Power Installed:


The following local instrumentation is provided on and around the crude oil transfer pumps: 10-PG-0322 10-PG-0323

Cause and Effects

P-1001A Discharge Pressure P-1001B Discharge Pressure

The Cause and Effect Chart associated with the Crude Oil Transfer Pumps are the same as those for the LP separator and are detailed on System 10.2 CUR-MAS-PB-20655.


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4.10 Electrostatic Coalescer V-1004 (Refer to P&ID Drg No CUR-MAS-PM-20046-001)

The electrostatic coalescer is designed to operate completely full of liquid and is used to separate crude oil and water by gravity and with the aid of an electrostatic field. The vessel may also be used to desalt the crude oil flow if required by the addition of industrial water to dilute the saline formation water. Fully stabilised crude from the duty crude oil transfer pump enters the bottom of the electrostatic coalescer through 8in pipework. The crude oil inlet pipework is fitted with a manual mixing valve upstream of the crude oil inlet nozzle. This is designed for use when the coalescer is being used to desalt the crude oil flow. When used for desalting the crude oil saline solution is diluted by the addition of industrial water through a hose connection on the crude oil inlet pipework. The flow of industrial water is monitored locally through Flow Gauge 10-FG-0415. The industrial water is mixed with the oil using a manual mixing valve fitted downstream of the industrial water connection. To ensure mixing, the mixing valve is partially closed to create a differential pressure across the valve. The differential pressure is monitored locally through Differential Pressure Gauge 10-PDG-0416. On entering the coalescer, the crude oil flow passes to a distribution pipe installed in the lower section of the vessel, below the grid formed by two electrode plates. The electrode plates are installed one above the other at or near to the vessel centre line to provide the maximum area of electrical field. As the crude outlet is on the top of the vessel, oil flows upward passing between the electrode plates. As the flow passes through the electrode plates the smaller water droplets entrained in the oil are encouraged to coalesce on receiving positive or negative charge from the electrodes. The small water droplets then combine to form larger water droplets which fall by gravity to the bottom of the vessel. The electrical field is generated by Power Unit L-1001. This is a 3:2 phase power unit which incorporates two single phase transformers each rated for 75kV. The two transformers are connected in a single case to provide two high voltage outputs which are connected to the two electrode grids. The power supply to the 75kV transformers fitted to the coalescer power pack is controlled from a remote control box. The power unit is started and stopped at the coalescer power pack control panel using start/stop switches 10-HS-0407 and 10-HS-0408 respectively. To prevent the formation of vapour inside the coalescer a back pressure is maintained within the vessel through LP Separator Oil Level Control Valve 10-LCV-0314 located downstream of Export Crude Oil Cooler E1004.


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4.10 Electrostatic Coalescer V-1004 (Continued)

Crude oil at stock tank specification leaves the top of the coalescer through 8in outlet pipework and flows through a manual isolation valve directly to the Export Crude Oil Cooler E-1004 for further processing. Separated water leaves the bottom of the vessel through 3in pipework and is returned to the inlet of MP Crude Oil Heater E-1002. The interface level in the coalescer is maintained by Interface Level Control Valve 10-LCV-0401 located on the water outlet line from the electrostatic coalescer to the MP crude oil heater. This level control valve is controlled through Interface Level Controller 10-LIC-0401 on signals from Level Transmitter 10-LT-0401. The level controller is equipped with PCS generated high and low level alarms which annunciate on PCS through 10-LAH-0401 and 10-LAL-0401 respectively. To allow the interface level to be manually checked five trycocks are provided at different intervals on the vessel. These allow a sample of the crude oil to be taken for analysis. The crude oil sample is drawn through 2in pipework which is routed through a trycock cooler. To prevent the risk of explosion the coalescer is provided with Low Level Switch 10-LSLL-0406 installed in the top of the vessel. This is designed to detect a build-up of gas within the vessel as a result of a low level. Activation of the switch trips the power unit, to remove a possible source of ignition, and is annunciated on PCS through 10-LALL-0406. Overpressure protection of the electrostatic coalescer is provided by Pressure Safety Relief Valves 10-PSV-0403A/B which are set at 16barg and relieve excess pressure to LP Flare. The valves are fitted with a valve interlock system which ensures that one relief valve is on line at all times.


The following local instrumentation is provided on and around the electrostatic coalescer: 10-LG-0414 10-PG-0405 10-TG-0404

Oil/Water interface level Vessel pressure Vessel temperature

Technical Data


Cause and Effect Charts

The Cause and Effect Chart associated with the electrostatic coalescer is System 10.2 CUR-MAS-PB-20655.


2900mm ID x 9650mm TT 16.0barg/FV -30oC/+85oC

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4.11 Export Crude Oil Cooler E-1004 (Refer to P&ID Drg No CUR-MAS-PM-20047-001)

The export crude oil cooler is a plate type heat exchanger designed to cool the crude oil flow to 30oC by heat exchange with cooling medium. Dehydrated crude from the oil outlet line of the electrostatic coalescer flows through 8in pipework to the inlet of the export crude oil cooler.

The flow of crude entering the cooler is metered by Vortex Meter 10-FT-0459. This provides flow indication on PCS through Flow Indicator 10-FI-0459. Temperature of the crude oil inlet flow is also monitored through Temperature Transmitter 10-TT-0452 located downstream of the vortex meter. This provides inlet temperature indication on PCS through Temperature Indicator 10-TI-0452. A manually operated isolation ball valve is fitted on the crude inlet to the export crude oil cooler. This valve is always in the open position as the export crude oil cooler is in continuous service unless a long term shutdown of the Oil Processing Facilities is in progress, when the cooler may be isolated for maintenance. Crude oil passes through the plate internals of the export crude oil cooler where the temperature of the oil is lowered to 30oC by heat exchange with cooling medium. The cooled oil flows out of the exchanger where it passes onwards to the cargo oil tanks for storage through Outlet Shutdown Valve 10-XV-0458 and Level Control Valve 10-LCV-0314. Outlet Shutdown Valve 10-XV-0458 is a pneumatically actuated valve which fails closed on loss of instrument air supply and is provided with position switches on the valve stem. These provide open and closed position indication on PCS through 10-ZI-0458. The flow of crude oil through the plate exchanger is controlled through Level Control Valve 10-LCV-0314. This valve is controlled through Level Controller 10-LIC-0314 on signals from Level Transmitter 10-LT-0314 located on the oil side of LP Separator V-1003. Level Control Valve 10-LCV-0314 is pneumatically operated and fails closed on loss of instrument air supply. A normally isolated 6in bypass line is provided around the valve for use in the event of control valve failure. Cooling medium is routed to the export crude oil cooler through 6in pipework from the cooling medium supply header. The cooling medium flow passes through the exchanger where heat is transferred from the hot crude oil flow to the cooling medium. After absorbing heat from the crude oil, the cooling medium passes out of the export crude oil cooler through Temperature Control Valve 10-TCV-0455 before flowing on to the cooling medium return circuit.


Page 35 / 36



4.11 Export Crude Oil Cooler E-1004 (Continued)

The flow of cooling medium through the export crude oil cooler is controlled by Temperature Controller 10-TIC-0455 on signals from Temperature Transmitter 10-TT-0455 located on the exchanger crude oil outlet line. The temperature controller modulates 10-TCV-0455 as required to maintain the control setpoint and is equipped with high and low temperature alarms through 10-TAH-0455 and 10-TAL-0455 respectively. The cooler is protected against high temperature through Temperature Transmitter 10-TT-0454 located in the crude oil outlet line. This provides crude oil outlet temperature indication on PCS through 10-TI-0454 and also provides a high temperature shutdown of the cooler through 10TAHH-0454. Activation of the high temperature condition is relayed to the PSD System. A dedicated sample point for crude oil sampling is fitted to the oil outlet line from the export crude oil cooler. Samples from this facility are taken and the crude oil analysed to ensure that the TVP specification of 0.83barg (max) @ 26.67oC is not exceeded.


The following local instrumentation is provided on and around the export crude oil cooler: 10-TG-0451 10-PG-0450 10-TG-0456 10-PG-0457 44-TG-2041 44-PG-2042 44-TG-2045 44-PG-2044

Crude oil to E-1004 temperature Crude oil to E-1004 pressure Crude oil from E-1004 temperature Crude oil from E-1004 pressure Cooling medium to E-1004 temperature Cooling medium to E-1004 pressure Cooling medium from E-1004 temperature Cooling medium from E-1004 pressure

Technical Data

Overall Dimensions:

2058m (L) x 626mm (W) x 2390mm (H) Design Pressure (Oil Side): 16.0barg Design Pressure (Cooling Medium Side): 16.0barg Design Temperature (Oil Side): -30oC to 85oC Design Temperature (Cooling Medium Side): 60oC Duty: 4740KW

Cause and Effects

The Cause and Effect Chart associated with the export crude oil cooler is System 10-2 CUR-MAS-PB-20655.


Page 36 / 36

Operating Procedures


Operating Procedures 5.01 5.01.1 5.01.2 5.01.3 5.01.4 5.01.5 5.01.6

Cold Start-up of the Oil Processing Facilities Preamble Plant Status Preconditions Cold Start-up Valve Checklist Start-up Overrides Cold Start-up Procedure

5.02 5.02.1 5.02.2 5.02.3 5.02.4 5.02.5

Hot Start-up of the Oil Processing Facilities Preamble Preconditions Hot Start-up PSD Valve Checklist Hot Start-up Overrides Hot Start-up Procedure

5.03

Normal Running

5.04 5.04.1 5.04.2 5.04.3

Planned Shutdown of the Oil Processing Facilities Preamble Preconditions Planned Shutdown Procedure

5.05 Unplanned Shutdown of the Oil Processing Facilities 5.05.1 Preamble 5.05.2 Unplanned Shutdown Procedure 5.06

Process and Emergency Cause and Effect Charts

5.07

Pressure Safety Valve Five Key Interlock Operations

Figures 5.01

Interlocked Pressure Safety Valves


Page 1 / 81


Operating Procedures 5.01 Cold Start-up of the Oil Processing Facilities 5.01.1 Preamble

This procedure covers the case of starting up all Curlew wells to Curlew FPSO as required to provide procedural coverage for all well start-ups. The assumed routing is Curlew wells DP1, DP2, DP3 and DP4 started up with commingling flow at the manifold through both Riser D1 and Riser D2 to the HP Separator. Well BP1 is assumed to be started up to the Test Separator through Riser B1. Procedure would need to be adapted appropriately to perform other start-up cases. The Curlew D wells are expected to be started up in the order DP1, DP2, DP4 and then DP3. Potentially DP3 and BP1 wells will not be under production. If well testing a Curlew D well then production from this well would be routed to the Test Separator. Well BP1 would not be produced if the Test Separator is being used for a Curlew D well. Based on erosional data results, if single riser production is used for all Curlew D wells this will require production deferment, ie. choking back on wells for initial years. If production rates up both Curlew D risers do not achieve arrival temperatures that exceed the wax appearance temperature of 35°C then Curlew D should be changed to single riser production, However, commingling flow via both flowlines hydraulically unconstrains Curlew D production as FTHP’s decline. Continuous wax inhibitor injection will be required if arrival temperatures remain below the wax appearance temperature. The wax inhibitor injection strategy would be provided by Production Engineering in this late-field case. Continuous scale inhibitor injection will be required when DP3 is produced and is expected to be required a few months into production from the DP4 well. The Scale Inhibition Strategy provides guidance and input will be provided to operators from Production Engineering at this stage. Manifold crossover valve 03-XV-1003 should be retained open for shutdowns/start-up if both flowlines are used during normal operation. This is in order to prevent pressure differentials over it and unnecessary damage to the valve seats from opening it. If changing to one flowline operation then the crossover valve 03-XV-1003 should be closed. The cold start-up procedure for the Oil Processing Facilities can be summarised in the following major steps:


Page 2 / 81



5.01.1 Preamble - Continued

•

Line up the oil flow from the Curlew D subsea wells to the HP Separator, MP Separator, MP Crude Oil Heater, LP Separator, Crude Oil Transfer Pump and Electrostatic Coalescer.

•

During start-up all gas produced is routed to the flares.

Line-up the produced water outlet from the HP and Test separators to the HP and Test hydrocyclone using the keyswitch selector and manual valves on water outlets to dispose of the produced water. •

Line-up the fully stabilised oil flow from the Electrostatic Coalescer through the Export Crude Oil Cooler to the Crude Storage Tanks until the oil processing facilities have achieved stable operating conditions.

•

Ensure that Heating Medium is available to the HP and MP Crude Oil Heaters.

. •

. •

•

Ensure that Cooling Medium is available to prepare the Export Crude Oil Cooler to receive stabilised crude oil from the Electrostatic Coalescer. If the separators have been depressurised it should be possible to repressurise them from produced gas. If necessary the separators may be pressurised using nitrogen for stability during start-up. Commence methanol injection to each Curlew D well sequentially to prevent the formation of hydrates in the flowlines during well start-ups. C ur l e w D H y dr a t e For ma t i on C ur v e s ( 1 °C Sa f e t y Fa c t or )

120. 00

100. 00

80. 00 Condensed Wat er P r oduc ed Wat er

60. 00

A r r i v al P r es sur e 40. 00

20. 00

0. 00 0. 00

5. 00

10. 00

15. 00

20. 00

25. 00

30. 00

T e mp e r a t u r e ( ° C )


Page 3 / 81




•

Start up the Curlew Well DP1 to the HP separator by slowly opening the subsea choke

•

Establish operating levels, pressures and temperatures in the HP Separator, then the MP separator, and then establish a flowrate through the MP Crude Oil Heater to the LP Separator. Reset the shutdown valves on the liquid outlets as the operating levels are established.

•

Start the duty Crude Oil Transfer Pump to fill the Electrostatic Coalescer and start the duty Produced Water Transfer Pump to direct any produced water recovered in the Coalescer back to the MP separator for further processing

• •

Start up the Curlew Well DP2 to the HP separator. Reset the PSD shutdown valves for Riser D1 and slowly open the topsides choke to start flowing through Riser D1 as well.

•

Start up the Curlew well DP4 to the HP separator.

•

Start up the Curlew well DP3 to the HP separator.

•

If required to start-up well BP1 then visually check Riser B1 topsides chokes are in the closed position and line up the oil flow from the well BP1 to the Test Separator.

•

Commence methanol injection and wax inhibitor to the Curlew B subsea well to prevent the formation of hydrates and wax deposition in the flowlines and topsides facilities during start-up

• •

Start up the Curlew Well BP1 to the Test separator. Establish operating levels, pressures and temperatures in the Test Separator.

Once the oil processing facilities have achieved stable operating conditions and the crude oil has achieved export specification of 0.83 barg (max) at 26.67oC direct the flowrate of dead crude from the Export Crude Oil Cooler to the Cargo Storage Tanks


Page 4 / 81


Operating Procedures 5.01.1 Preamble - Continued

Limitations to Single Riser Production Due to Sand

This cold start-up procedure must be read in conjunction with the cold start-up procedures of the following systems: •

Volume 1 Book A - Subsea Facilities

•

Volume 1 Book C - Gas Processing Facilities

•

Volume 1 Book D - Produced Water Facilities

•

Volume 1 Book K - Fuel Gas System

•

Volume 1 Book M - Chemical Injection

•

Volume 2 Book A - Crude Oil Storage and Offloading

The following details simulation results of the reduction in riser life while producing through a single riser due to the effect of sand associated with production flow rates. On observing sand measurements above 1.3lb/1000bbl liquid consultation should be taken with Production Engineering to determine optimal production rates.

Max Flow Rate 100 MMscfd

GOR 4,600 scf/bbl (819 m3/m3) Water cut 0% Liquid rate 21,739 bbl/d (3,456 m3/d) Arrival pressure 42 barg Sand content 10 lb/1000bbl for 6months then 5lb/1000bbl for residual service life 10 lb/1000bbl for 6months then 1.3lb/1000bl for residual service life

5.01.2

Calculated Life (yrs) 0.5 + 3.75 0.5 + 14.5

Following completion of all maintenance activities within the boundary


Page 5 / 81


Operating Procedures Plant Status

isolation, as detailed in Procedure 6.15 Oil Processing Facilities Boundary Reinstatement in Part 6 of this Volume, all equipment has now undergone pre-start pressure testing to 95% of the relief valve lifting pressures. It is only after successful pre-start pressure tests, as witnessed by the Operations Supervisor, that the boundary isolation can be lifted and the cold start-up procedure undertaken. Various ‘Cold Start-up’ and operating scenarios are possible, depending on the level of shutdown and the status of the production flowlines and oil processing facilities. A full listing of these is given in Section 2 of the MAS Alliance Curlew Field Development Project - Oil and Gas Operability Review (Document Number CUR-MAS-G-O-50030). In later Curlew field life the following factors will change: •

The expected flowrates of well fluids from the subsea production wells

•

Line-up of the hydrocyclones in the produced water facilities

•

Depletion of produced gas from the oil processing facilities

•

Injection of increased quantities of methanol during the Cold Startup when the water cut of the well fluids has increased

This procedure is for starting the oil processing facilities from a cold start, ie the facilities have been shut down for some time and the temperature of the crude oil in the flowlines from the subsea production facilities has achieved the minimum seabed temperature of 4°C. The D1 and D2 flowline pressures have been blown-down to 10 barg to prevent hydrate formation on start-up. The B1 flowline pressure has been blown-down to <2 barg to prevent hydrate formation and to help kick-off the depleted well. If the shutdown was planned, then methanol has been injected in the production flowlines.


Page 6 / 81



5.01.3 Preconditions

WARNING: ALL SYSTEM PRESSURE SAFETY RELIEF VALVES MUST BE LINED UP FOR NORMAL OPERATION. (1)

No Permits to Work or electrical isolations are in force which may prohibit system start-up.

(2)

The Fire and Gas Detection/Protection, Process Control System (PCS) and Safety Related Systems (PSDs) are operational along with the alarms, trips, and controllers.

(3)

All spades and spectacle blinds are in the correct positions as per the P&IDs.

(4)

All drains, vents, integral double block and bleed assemblies, sandwash valves, purge and sample points are closed and blanked where necessary.

(5)

All instrument and level bridle drain valves are closed.

(6)

All instrument isolation valves are open.

(7)

The following utility systems are available: • Electrical Power Distribution (including trace heating) • Instrument Air • Heating Medium • Cooling Medium (including cooling seawater)

(8)

Chemical Injection Package including the availability of the following chemicals, as required: • Methanol • Demulsifier • Anti-foam • Scale Inhibitor • Corrosion Inhibitor • Wax Inhibitor • HP Flare System (requires N 2 purge)


Page 7 / 81



5.01.3 PreconditionsContinued

• LP Flare System (requires N 2 purge) • Hazardous Open Drains (9)

Ensure that the Gas Compression Facilities are prepared to receive the process gas from the Test, HP, MP and LP separators included in the Oil Processing Facilities.

(10)

Ensure that Glycol Circulation has been initiated and the glycol is up to temperature in the Gas Dehydration System. Note that the Glycol system can be operated on the ‘short loop’, Surge Drum to Flash Drum, whilst the plant is shutdown.

(11)

The produced water disposal facilities are available for use.

(12)

Communications have been established between all personnel involved in this procedure.

(13)

All HVAC and Turret Annulus Fans have been restarted.


Page 8 / 81



5.01.4 Cold Start-up Valve Checklist

Refer to Figures 3.01 to 3.08 in Section 3 of this Volume and the P&IDs identified below. (1)

The System Operator should CHECK the following valves to confirm the valve settings are as given below.

(2)

Where the valves are found to be out of position, the operator should satisfy himself that it is safe to move the valves before doing so.

Subsea Production Well Curlew ‘B’ (BP1) - Valve Checklist Ref P&ID No (CUR-MAS-PB-20021-003)

Valve Tag

Valve Description

Setting

03-AMV-0204

Annulus Master Valve Well BP1

OPEN

03-ASV-0202

Annulus Swab Valve Well BP1

CLOSED

03-AXOV-0201

Annulus Crossover Valve Well BP1

CLOSED

03-SSSV-0211

Subsurface Safety Valve Well BP1

CLOSED

03-PUMV-0205

Production Upper Master Valve Well BP1

CLOSED

03-PSV-0203

Production Swab Valve Well BP1

CLOSED

03-PWV-0206

Production Wing Valve Well BP1

CLOSED

03-PCV-0208

Production Choke Valve Well BP1

CLOSED

03-MIV-0207

Methanol Injection Valve Well BP1

CLOSED


Page 9 / 81



Subsea Production Well Curlew ‘D’ (DP1) - Valve Checklist Ref P&ID No (MAERSK DRILLING AUSTRALIA-CP692-B-20021-001 Rev C1)

Valve Tag

Valve Description

Setting

03-AMV-0004

Annulus Master Valve Well DP1

OPEN

03-ASV-0002

Annulus Swab Valve Well DP1

CLOSED

03-AXOV-0001

Annulus Crossover Valve Well DP1

CLOSED

03-SSSV-0011

Subsurface Safety Valve Well DP1

CLOSED

03-PUMV-0005

Production Upper Master Valve Well DP1

CLOSED

03-PSV-0003

Production Swab Valve Well DP1

CLOSED

03-PWV-0006

Production Wing Valve Well DP1

CLOSED

03-PCV-0008

Production Choke Valve Well DP1

CLOSED

03-MIV-0007

Methanol Injection Valve Well DP1

CLOSED

03-PTIV-0010

Production Test Isolation Valve Well DP1

CLOSED


Page 10 / 81




Valve Tag

Valve Description

Setting

03-AMV-0104


OPEN

03-ASV-0102


CLOSED

03-AXOV-0101


CLOSED

03-SSSV-0111


CLOSED

03-PUMV-0105


CLOSED

03-PSV-0103


CLOSED

03-PWV-0106


CLOSED

03-PCV-0108


CLOSED

03-MIV-0107


CLOSED


Page 11 / 81




Valve Tag

Valve Description

Setting

03-AMV-0304


OPEN

03-ASV-0302


CLOSED

03-AXOV-0301


CLOSED

03-SSSV-0311


CLOSED

03-PUMV-0305


CLOSED

03-PSV-0303


CLOSED

03-PWV-0306


CLOSED

03-PCV-0308


CLOSED

03-MIV-0307


CLOSED


Page 12 / 81




Valve Tag

Valve Description

Setting

03-AMV-1104


OPEN

03-ASV-1102


CLOSED

03-AXOV-1101


CLOSED

03-SSSV-1111


CLOSED

03-PUMV-1105


CLOSED

03-PSV-1103


CLOSED

03-PWV-1106


CLOSED

03-PCV-1108


CLOSED

03-MIV-1107


CLOSED

03-CIV1-1113

Chemical Injection Valve

CLOSED

03-CIV2-1114

Chemical Injection Valve

CLOSED


Page 13 / 81



Subsea Production Manifold Curlew ‘D’ - Valve Checklist Ref P&ID No (MAERSK DRILLING AUSTRALIA-CP692-U-20021-001 Rev C1)

Valve Tag

Valve Description

Setting

03-XV-1001

Riser D2 Manifold Isolation Valve

OPEN

03-XV-1002


OPEN

03-XV-1003

Crossover Isolation Valve

OPEN


Page 14 / 81



Production Flowlines - Valve Checklist Ref P&ID No (CUR-MAS-TP-42002-001 Rev C8) Valve Tag 07-XXV-100

Valve Description Curlew Riser D2 ESD Valve

Setting CLOSED (Set for Start-up)

07- HV-002

Isolation Valve for Riser D2 carcass Vent No 1

LOCKED OPEN

07-HV-003


LOCKED OPEN

07-HV-004

Double block and bleed valves for Riser D2 low point drain

CLOSED

07-HV-005

Double block and bleed valves for squeeze/diesel injection point for Riser D2

CLOSED

07-HV-006

Double block and bleed valves for methanol injection point for Riser D2

CLOSED (Set for Start-up)

07-XV-105

Riser D2 ESD Valve


Topsides Choke Valve Riser D2

CLOSED (Set for Start-Up)

07-HV-008

Double block and bleed valves for corrosion inhibitor injection point for Riser D2

OPEN

07-HV-009


CLOSED

07-XV-402

Riser D2 Test Diverter Valve


07-XV-110

Riser D2 Production Diverter Valve


Curlew Riser D1 ESD Valve


07-HV-012


LOCKED OPEN

07-HV-013


LOCKED OPEN

07-PCV-109

07-XXV-200


Page 15 / 81



Production Flowlines - Valve Checklist (Continued) Valve Tag 07-HV-014

Valve Description Double block and bleed valves for Riser D1 low point drain

Setting CLOSED

07-HV-015

Double block and bleed valves for squeeze/diesel injection point for Riser D1

CLOSED

07-HV016

Double block and bleed valves for methanol injection point for Riser D1


07-XV-205

Riser D1 ESD Valve


Topsides Choke Valve Riser D1


07-HV018

Double block and bleed valves for corrosion inhibitor injection point for Riser D1

OPEN

07-HV019


CLOSED

07-XV-403

Riser D1 Test Diverter Valve


07-XV-210

Riser D1 Production Diverter Valve


Riser B1 ESD Valve


07-HV022

Isolation Valve for Riser B1 carcass Vent No 1

LOCKED OPEN

07-HV-023

Isolation Valve for Riser B1 carcass Vent No 2

LOCKED OPEN

07-HV-024

Double block and bleed valves for Riser B1 low point drain

CLOSED

07-HV-025

Double block and bleed valves for squeeze/diesel injection point for Riser B1

CLOSED

07-HV-026

Double block and bleed valves for methanol injection point for Riser B1


07-XV-305

Riser B1 ESD Valve


07-PCV-209

07-XXV-300


Page 16 / 81



Production Flowlines - Valve Checklist (Continued) Valve Tag 07-PCV-309

Valve Description

Setting

Topsides Choke Valve Riser B1


07-HV-028

Double block and bleed valves for corrosion inhibitor injection point for Riser B1

OPEN

07-HV-029

Double block and bleed valves for Riser B1 low point drain

CLOSED

07-XV-404

Riser B1 Test Diverter Valve


07-XV-310

Riser B1 Production Diverter Valve



Page 17 / 81



Swivel Stack Leak Recuperation System - Valve Checklist Ref P&ID No (CUR-MAS-TM-41096-001) Valve Tag

Valve Description

Setting

07 HV-046

Three way valve for 8in Gas Swivel X-0701 (top seal ring) to the leak recuperation tank

OPEN (Set for Start-up)

07 HV-045

Three way valve for 8in Gas Swivel X-0701 (bottom seal ring) to the leak recuperation tank


07 HV-044

Three way valve for 8in Curlew B Production Swivel X-0704 (top seal ring) to the leak recuperation tank


07 HV-043

Three way valve for 8in Curlew B Production Swivel X-0704 (bottom seal ring) to the leak recuperation tank


07 HV-042

Three way valve for 8in Curlew D Production Swivel X-0703 (top seal ring) to the leak recuperation tank


07 HV-041

Three way valve for 8in Curlew D Production Swivel X-0703 (bottom seal ring) to the leak recuperation tank


07 HV-040

Three way valve for 8in Test Swivel X-0705 (top seal ring) to the leak recuperation tank


07 HV-039

Three way valve for 8in Test Swivel X-0705 (bottom seal ring) to the leak recuperation tank


07 HV-037

2in isolation valve for Leak Recuperation Tank T-0705 to the Hazardous Open Drains

LOCKED OPEN


Page 18 / 81



Test Separator - Valve Checklist Ref P&ID No (CUR-MAS-PM-20048-501 and CUR-MAS-PB-20048-002) Valve Tag

Valve Description

Setting

HV-10260/1

10in Isolation valves for the inlet header to the Test separator

LOCKED OPEN

HV-73007

½in Isolation valve for the demulsifier dosing point at the Test separator inlet

OPEN (If required)

HV-73009

½in Isolation valve for the anti-foam dosing point at the Test separator inlet

OPEN (If required)

HV- 10307

6in Isolation valve for the inlet to Pressure Safety Relief Valve 10-PSV- INTERLOCKED OPEN 0503A

HV-10243/4

6in Isolation valve for the outlet from Pressure Safety Relief Valve INTERLOCKED OPEN 10-PSV-0503A to the HP Flare

HV- 10308

6in Isolation valve for the inlet to Pressure Safety Relief Valve 10-PSV- INTERLOCKED CLOSED 0503B

HV-10248/9

6in Isolation valve for the outlet from Pressure Safety Relief Valve INTERLOCKED OPEN 10-PSV-0503B to the HP Flare

HV-10251

1st in line isolation valve on bypass line for 10-PSV-0503A and B

CLOSED

HV-10250

2nd in line isolation valve on bypass line for 10-PSV-0503A and B

CLOSED

Blowdown Valve to the HP Flare

CLOSED

HV-10239

8in Isolation valve downstream of 10-XV-0501

LOCKED OPEN

HV-10237

1st in line isolation valve on manual depressurisation line to LP Flare

CLOSED

HV-10236

2nd in line isolation valve on manual depressurisation line to LP Flare

CLOSED

10-XV-0501

HV-10253/4

Single twin seal valve downstream of 10-PCV-0507B on Test separator OPEN gas outlet line to the HP flare

HV-10258/9

Single twin seal valve downstream of 10-PCV-0507A on Test separator OPEN gas outlet line to gas compression


Page 19 / 81


Operating Procedures Valve Tag 20-XV-1191

Valve Description PSD isolation valve for Test separator gas outlet line


Setting CLOSED

Page 20 / 81



Test Separator - Valve Checklist (Continued) Valve Tag

Valve Description

Setting

HV-52003

10in Isolation ball valve downstream of 20-XV-1191 for Test separator gas to LOCKED the fuel gas cooler E-5202 CLOSED

HV-20072

10in Isolation ball valve downstream of 20-XV-1191 for Test separator gas to CLOSED MP Separator V-1002 (Set for Start-up)

HV-20071

10in Isolation ball valve downstream of 20-XV-1191 for Test separator gas to CLOSED the MP compressor cooler E-1002 (Set for Start-up)

HV-20073

10in Isolation ball valve downstream of 20-XV-1191 for Test separator gas to CLOSED the Inlet Cooler E-2201 (Set for Start-up)

HV-10282

6in Manual isolation ball valve for Test separator oil outlet line

OPEN

PSD Isolation valve for Test separator oil outlet line

CLOSED

10-XV-0518 HV-10285

6in Isolation ball valve upstream of 10-LCV-0514 for Test separator oil outlet OPEN line

HV-10286

6in Isolation ball valve downstream of 10-LCV-0514

OPEN

HV-10289

3in isolation globe valve for 10-LCV-0514 bypass line

CLOSED

HV-10077

6in Isolation ball valve on the line from the Test separator oil outlet to the MP OPEN separator (Set for Start-up)

HV-10122

6in Isolation ball valve on the line from the Test separator oil outlet to the MP CLOSED crude oil heater (Set for Start-up) 4in Manual isolation ball valve for Test separator produced water outlet line OPEN

HV-10281 -

Isolation valve(s) for the spare chemical injection point to the Test separator CLOSED produced water outlet line

HV-10273

Manual Jetting Water Valve No 1 from the jetting water inlet manifold to the Test separator

CLOSED

HV-10275


CLOSED


Page 21 / 81



Test Separator - Valve Checklist (Continued) Valve Tag

Valve Description

Setting

HV-10277


CLOSED

HV-10278

Isolation ball valve from the jetting water inlet manifold to the skid drip pan

CLOSED

HV-10304

4in Isolation valve between the Test separator V-1005 and the Test OPEN Hydrocyclone V-4003 (When V-1005 is Lined Up to V-4003)

HV-10305

4in Isolation valve between the HP Separator V-1001 and the Test CLOSED Hydrocyclone V-4003 (When V-1005 is Lined Up to V-4003)

HV-10306

Low point drain valve in the produced water cross-over between the HP CLOSED Separator and the Test Hydrocyclone

HV-10321 & 3in Isolation valve in the jet mix nozzle supply from the crude oil fast loop OPEN HV-10322 sampling system (When Hooked Up) HV-10319 & 4in Isolation valve in crude the supply line to the fast loop sampling system OPEN HV-10320 (When Hooked Up) HV-73316

Integrated DB&B and check valve for the H2S Scavenger injection


OPEN

Page 22 / 81



HP Separator - Valve Checklist Ref P&ID Nos (CUR MAS-PMT-20041-501 and CUR-MAS-PB-20041-002) Valve Tag HV-10013/4

Valve Description

Setting

14in Isolation valve for the inlet header to the HP Separator

LOCKED OPEN

HV-73001

½in Isolation valve for the demulsifier dosing point at the HP separator inlet

OPEN

HV-73002

½in Isolation valve for the anti-foam dosing point at the HP separator inlet

OPEN

HV10019/20

6in Isolation valve for the inlet to Pressure Safety Relief Valve INTERLOCKED OPEN 10-PSV-0103A

HV-1023/4

8in Isolation valve for the outlet from Pressure Safety Relief Valve INTERLOCKED OPEN 10-PSV-0103A to the HP Flare

HV-10025/6

6in Isolation valve for the inlet to Pressure Safety Relief Valve INTERLOCKED CLOSED 10-PSV-0103B

HV10029/30

8in Isolation valve for the outlet from Pressure Safety Relief Valve INTERLOCKED OPEN 10-PSV-0103B to the HP Flare

HV-10032


CLOSED

HV-10031


CLOSED

Blowdown Valve to the HP Flare

CLOSED

HV-10033


LOCKED OPEN

HV-10015

1st in line isolation valve on manual depressurisation line to LP Flare

CLOSED

HV-10017

2nd in line isolation valve on manual depressurisation line to LP Flare

CLOSED

HV-10018

3rd in line isolation valve on manual depressurisation line to LP Flare

CLOSED

HV-22001

Isolation ball valve downstream of 10-PCV-0107 on HP separator gas OPEN outlet line to the HP flare

HV-52001

4in Isolation ball valve for the fuel gas supply from HP separator gas CLOSED outlet line to the fuel gas cooler E-5202 (Set for Start-up)

10-XV-0101


Page 23 / 81



HP Separator - Valve Checklist (Continued) Valve Tag

Valve Description

Setting

20-XV-1051

PSD Isolation Valve on HP separator gas outlet line

CLOSED

20-XV-1052

Pressurisation Bypass Valve for Test separator gas outlet line

CLOSED

HV-10048

6in Manual isolation ball valve for HP separator oil outlet line

OPEN

PSD Isolation Valve for HP separator oil outlet line

CLOSED

HV-10046

6in Manual isolation ball valve for HP separator produced water outlet line

OPEN

-

Isolation valve(s) for the spare chemical injection point to the HP separator produced water outlet line

CLOSED

HV-10037

Manual Jetting Water Valve No 1 from the jetting water inlet manifold to the HP separator

CLOSED

HV-10039


CLOSED

HV-10041


CLOSED

HV-10043


CLOSED

HV-10060


CLOSED

HV-10059

Isolation ball valve for the jetting water inlet manifold to the skid drip pan

CLOSED

HV-10300

Low point drain valve in the produced water cross-over between the Test CLOSED separator and the HP Hydrocyclone

HV-10301

6in Isolation valve between the Test separator V-1005 and the HP CLOSED Hydrocyclone V-4001 (When V-1001 is Lined Up to V-4001)

HV-10302

4in Isolation valve between the HP Separator V-1001 and the Test CLOSED Hydrocyclone V-4003 (When V-1001 is Lined Up to

10-XV-0118


Page 24 / 81


Operating Procedures Valve Tag

Valve Description

Setting V-4001)

HP Separator - Valve Checklist (Continued) Valve Tag HV-10303

Valve Description

Setting

6in Isolation valve between the HP Separator V-1001 and the HP OPEN Hydrocyclone V-4001 (When V-1001 is Lined Up to V-4001)

HV-10314 & 3in Isolation valve in the jet mix nozzle supply from the crude oil fast loop OPEN HV-10317 sampling system (When Hooked Up) HV-73322

Integrated DB&B and check valve for the H2S Scavenger injection


CLOSED

Page 25 / 81


Operating Procedures HP Crude Oil Heater - Valve Checklist

Ref P&ID No (CUR-MAS-PM-20042-501) Valve Tag

Valve Description

Setting

HV-10061/2

6in Isolation ball valve on the crude inlet to the HP crude oil heater

OPEN

HV-10063/4

6in Isolation ball valve on the crude outlet from the HP crude oil heater

OPEN

4in Isolation ball valve on the crude bypass for the crude oil heater

CLOSED

HV-10065 HV-10068/9

6in Double block and bleed valves upstream of 10-LCV-0114 on the oil OPEN outlet line from the HP crude oil heater

HV-10070/1

10in Double block and bleed valves downstream of 10-LCV-0114

OPEN

HV-10073

3in Isolation globe valve on 10-LCV-0114 bypass line

CLOSED

HV-10067

2in Isolation valve for 10-PSV-0153 discharge to the HP flare

LOCKED OPEN

HV-44054

4in Manual isolation valve for the Heating Medium Supply to the HP crude oil OPEN heater

HV-44058

4in Isolation ball valve upstream of 10-TCV-0155 on the heating medium OPEN outlet line from the HP crude oil heater

HV-44059

4in Isolation valve downstream of 10-TCV-0155

OPEN

HV-44062

3in Isolation globe valve on 10-TCV-0155 bypass line

CLOSED

44-XV-2017

Shutdown valve for the Heating Medium Return from the HP crude oil heater CLOSED

HV-10313 & 4in Isolation valve in crude the supply line to the fast loop sampling system OPEN HV-10316 (When Hooked Up)


Page 26 / 81



MP Separator - Valve Checklist Ref P&ID No (CUR-MAS-PM-20043501 and CUR-MAS-PB-20043-002) Valve Tag

Valve Description

HV-10075

10in Isolation ball valve on the inlet header for the Curlew B well to the MP separator

LOCKED OPEN (Set for Start-up)

HV-10076

10in Isolation ball valve on the inlet line from the HP crude heater to the MP separator


HV-10077

6in Isolation ball valve on the inlet line from the Test separator to the MP separator


HV-10078

2in Isolation ball valve on the discharge line from the produced water pumps to the MP separator inlet header


HV-73004

½in Isolation valve for the demulsifier dosing point at the MP separator inlet header

OPEN (If required)

HV-73006

½in Isolation valve for the anti-foam dosing point at the MP separator inlet header

OPEN (If required)

HV-10081


HV-10083

8in Isolation valve for the outlet from Pressure Safety Relief Valve INTERLOCKED OPEN 10-PSV-0203A to the LP Flare

HV-10084


HV-10086

8in Isolation valve for the outlet from Pressure Safety Relief Valve INTERLOCKED OPEN 10-PSV-0203B to the LP Flare

HV-10088


CLOSED

HV-10087


CLOSED

Blowdown Valve to the LP Flare

CLOSED

HV-10079


LOCKED OPEN

HV-10090

Isolation ball valve downstream of 10-PCV-0207B

OPEN

PSD isolation valve for MP separator gas outlet line

CLOSED

10-XV-0201

20-XV-1201


Setting

Page 27 / 81



Valve Description

Setting

MP Separator - Valve Checklist (Continued) Valve Tag

Valve Description

Setting

20-XV-1202

Pressurisation bypass valve for MP separator gas outlet line

CLOSED

HV-10114

8in Manual isolation ball valve for MP separator oil outlet line

OPEN

PSD Isolation Valve for MP separator oil outlet line

CLOSED

10-XV-0218 HV-10118

8in Isolation ball valve upstream of 10-LCV-0214 on MP separator oil outlet OPEN line

HV-10119


OPEN

HV-10080


CLOSED

HV-10112

6in Manual isolation ball valve for MP separator produced water outlet line OPEN

HV-10102

Manual Jetting Water Valve No 1 from the jetting water inlet manifold to the MP separator

CLOSED

HV-10104


CLOSED

HV-10106


CLOSED

HV-10108


CLOSED

HV-10110


CLOSED

HV-10115


CLOSED


Page 28 / 81



MP Crude Oil Heater - Valve Checklist Ref P&ID No (CUR-MAS-PM-20044-501) Valve Tag

Valve Description

Setting

HV-10123

16in Isolation ball valve on the crude inlet to the MP crude oil heater

OPEN

HV-10125

20in Isolation ball valve on the crude outlet from the MP crude oil heater

OPEN

HV-10126

Isolation valve for 10-PSV-0253 outlet to the LP flare

LOCKED OPEN

HV-44064

6in Manual isolation valve for the Heating Medium Supply to the MP crude OPEN oil heater (Set for Start-up)

HV-44067

6in Isolation ball valve upstream of 10-TCV-0255 on the heating medium OPEN outlet line from the MP crude oil heater

HV-44068


OPEN

HV-44071


CLOSED

HV-44072

6in Manual isolation valve on the Heating Medium Return from the MP crude OPEN oil heater (Set for Start-up)


Page 29 / 81



LP Separator, Crude Oil Transfer Pumps and Produced Water Transfer Pumps Valve Checklist Ref P&ID Nos (CUR-MAS-PM-20045-501 and CUR-MAS-PB-20045-002) Valve Tag

Valve Description

Setting

HV-10127


HV-10129


HV-10130


HV-10132


HV-10134


CLOSED

HV-10133


CLOSED

Blowdown Valve to the LP Flare

CLOSED

HV-10135


LOCKED OPEN

HV-10136

Isolation ball valve downstream of 10-PCV-0307B

OPEN

20-XV-1221

PSD isolation Valve for LP separator gas outlet line

CLOSED

20-XV-334

PSD isolation Valve for LP separator produced water outlet line

CLOSED

20-XV-335

PSD isolation Valve for LP separator crude oil outlet line

CLOSED

HV-10140

Manual Jetting Water Valve No 1 from the jetting water inlet manifold to the LP separator

CLOSED

HV-10142


CLOSED

HV-10144


CLOSED

HV-10146


CLOSED

10-XV-0301


Page 30 / 81



LP Separator, Crude Oil Transfer Pumps and Produced Water Transfer Pumps Valve Checklist (Continued) Valve Tag

Valve Description

Setting

HV-10148


CLOSED

HV-10170


CLOSED

HV-10162

12in Isolation ball valve for Crude Oil Transfer Pump P-1001A suction line

OPEN

HV-10168

8in Isolation ball valve for P-1001A discharge line

OPEN

HV-10165

12in Isolation ball valve for Crude Oil Transfer Pump P-1001B suction line

OPEN

HV-10169

8in Isolation ball valve for P-1001B discharge line

OPEN

HV-10174

3in Isolation ball valve for Produced Water Transfer Pump P-1002A suction line

OPEN

HV-10176

2in Isolation ball valve for P-1002A discharge line

OPEN

HV-10171

3in Isolation ball valve for Produced Water Transfer Pump P-1002B suction line

OPEN

HV-10173

2in Isolation ball valve for P-1002B discharge line

OPEN


Page 31 / 81



Electrostatic Coalescer - Valve Checklist Ref P&ID No (CUR-MAS-PM-20046-501) Valve Tag -

Valve Description

Setting

Mix valve on the discharge line from the crude oil transfer pumps to the FULLY electrostatic coalescer OPEN

HV-10224

1st in line isolation ball valve on the water supply to the mix valve

CLOSED

HV-10223

2nd in line isolation ball valve on the water supply to the mix valve

CLOSED

HV-10218

3in Isolation ball valve upstream of 10-LCV-0401 on the produced water OPEN outlet from the electrostatic coalescer

HV-10219


OPEN

HV-10222


CLOSED

HV-10188

8in Isolation Valve for the electrostatic coalescer oil outlet line

OPEN

HV-10185

4in Isolation valve for the inlet to Pressure Safety Relief Valve 10-PSV- INTERLOCKED OPEN 0403A

HV-10187


HV-10182

4in Isolation valve for the inlet to Pressure Safety Relief Valve 10-PSV- INTERLOCKED CLOSED 0403B

HV-10184


HV-10188


OPEN

HV-10189


CLOSED

HV-10208

Trycock valve from Nozzle N6A to cooler

CLOSED

HV-10213

Outlet valve from trycock cooler - Nozzle N6A

CLOSED

HV-10209

Trycock valve from Nozzle N6B to cooler

CLOSED

HV-10214

Outlet valve from trycock cooler - Nozzle N6B

CLOSED

HV-10210

Trycock valve from Nozzle N6C to cooler

CLOSED


Page 32 / 81


Operating Procedures Valve Tag HV-10215

Valve Description Outlet valve from trycock cooler - Nozzle N6C

Setting CLOSED

Electrostatic Coalescer - Valve Checklist (Continued) Valve Tag

Valve Description

Setting

HV-10211

Trycock valve from Nozzle N6D to cooler

CLOSED

HV-10216

Outlet valve from trycock cooler - Nozzle N6D

CLOSED

HV-10212

Trycock valve from Nozzle N6E to cooler

CLOSED

HV-10217

Outlet valve from trycock cooler - Nozzle N6E

CLOSED

HV-10198

Drain valve for coalescer bushings at Nozzle N5A

CLOSED

HV-10195

Vent valve for coalescer bushings at Nozzle N5A

OPEN

HV-10196

Isolation valve for coalescer bushings vent (Nozzle N5A) to oil outlet line OPEN from the coalescer

HV-10197

Isolation valve for coalescer bushings vent (Nozzle N5A) to drainage

CLOSED

HV-10202

Drain valve for coalescer bushings at Nozzle N5B

CLOSED

HV-10199

Vent valve for coalescer bushings at Nozzle N5B

OPEN

HV-10200

Isolation valve for coalescer bushings vent (Nozzle N5B) to oil outlet line OPEN from the coalescer

HV-10201

Isolation valve for coalescer bushings vent (Nozzle N5B) to drainage


CLOSED

Page 33 / 81



Export Crude Oil Cooler - Valve Checklist Ref P&ID No (CUR-MAS-PM-20047-501) Valve Tag

Valve Description

Setting

HV-10225

8in Isolation ball valve on the crude inlet to the export crude oil cooler

OPEN

HV-10229

8in Isolation ball valve on the crude outlet from the export crude oil cooler

OPEN

PSD isolation valve for the crude outlet from the export crude oil cooler

CLOSED

10-XV-0458 HV-10230

8in Isolation ball valve upstream of 10-LCV-0314 on the crude outlet from OPEN the export crude oil cooler

HV-10231

8in Isolation valve downstream of 10-LCV-0314

OPEN

HV-10234


CLOSED

HV-45103

6in Manual isolation valve for the Cooling Medium Supply to the export crude OPEN oil cooler

HV-45096

6in Isolation ball valve upstream of 10-TCV-0455 on the cooling medium OPEN outlet line from the export crude oil cooler

HV-45097


OPEN

HV-45100


CLOSED

HV-45101

6in Manual isolation valve on the Heating Medium Return from the export OPEN crude oil cooler


Page 34 / 81



During the cold start-up of the Oil Processing Facilities the following shutdown inputs to the Shutdown System require to be overridden at the shutdown panel until steady operating conditions have been achieved.

5.01.5 Start-up Overrides

Switch

Equipment Tag No

Description

Shutdown Level

03-PALL-0016, 0116, 0316, 1116

-

Wellheads

PSD

07-PALL-101, 201 and 301

-

Production Risers

PSD

10-LALL-0510

V-1005

Test separator Oil/Water Interface Level

PSD

10-LALL-0512

V-1005

Test separator Gas/Oil Interface Level

PSD

10-PALL-0508

V-1005

Test separator Pressure

PSD

10-LALL-0110

V-1001

HP Separator Oil/Water Interface Level

PSD

10-LALL-0112

V-1001

HP Separator Gas/Oil Interface Level

PSD

10-PALL-0108

V-1001

HP Separator Pressure

PSD

10-LALL-0210

V-1002

MP Separator Oil/Water Interface Level

PSD

10-LALL-0212

V-1002

MP Separator Gas/Oil Interface Level

PSD

10-PALL-0208

V-1002

MP Separator Pressure

PSD

10-LALL-0310

V-1003

LP Separator Oil/Water Interface Level

PSD

10-LALL-0312

V-1003

LP Separator Gas/Oil Interface Level

PSD

10-PALL-0308

V-1003

LP Separator Pressure

PSD


Page 35 / 81


Operating Procedures 5.01.6 Cold Start-up Procedure STEP

DESCRIPTION

LOCAL

PCS

Refer to Figures 3.01 to 3.03 in Section 3 of this Book while reading the following procedure. 1

INFORM the Marine Supervisor that crude oil will shortly be available for loading. The Marine Supervisor will select the appropriate tank loading sequence and OPEN the appropriate valves to the cargo tank.

2

SET the controllers for the HP Separator as follows: •

Vessel Pressure Controller 10-PIC-0107 to AUTO with a setpoint of 10 barg. This setpoint will provide flowline hydrate mitigation.

*

•

Field production routing keyswitch positioned at 76-XS-1000A in order to confirm Curlew production is routed to the HP Separator.

CCR

•

Produced water routing keyswitch positioned at 40-HS-4000A in order to align the HP Separator Hydrocyclone to the HP Separator.

CCR

Note: Depending on the field water production rate anticipated, it is important that the correct hydrocyclone unit is lined up. The HP Hydrocyclone and the Test Hydrocyclone are rated to 18,000 BWPD and 5,000 BWPD respectively.

3

•

Oil/water Interface Level Controller 10-LIC-0111 to MANUAL with the Level Control Valve 10-LCV-0111 positioned on the clean water outlet from the HP Separator hydrocyclone CLOSED.

*

•

Oil/gas Interface Level Controller 10-LIC-0114 to MANUAL with the Level Control Valve 10-LCV-0114 CLOSED.

*

SET the controllers for the MP Separator as follows: •

Vessel Pressure Controller 10-PIC-0207 to AUTO with a setpoint of 7.7 barg.

*

•

Oil/water Interface Level Controller 10-LIC-0211 to MANUAL with the Level Control Valve 10-LCV-0211 positioned on the water outlet to the MP Separator hydrocyclone CLOSED.

*

•


*


Page 36 / 81


Operating Procedures 5.01.6 Cold Start-up Procedure - Continued STEP 4

5

DESCRIPTION

LOCAL

PCS

SET the controllers for the LP Separator as follows: •

Vessel Pressure Controller 10-PIC-0307 to AUTO with a setpoint of 0.7 barg.

*

•

Once an operable level has been established, set the oil/water Interface Level Controller 10-LIC-0311 to AUTO and Produced Water Transfer Pumps P-1002A/B to AUTO. Any produced water separated in the LP separator is pumped back to the MP separator for further processing by the duty selected produced water transfer pump on demand.

*

•

Oil/gas Interface Level Controller 10-LIC-0314 to MANUAL with the Level Control Valve 10-LCV-0314 CLOSED. The crude oil recovered in the LP separator is pumped to the downstream Electrostatic Coalescer for further processing under flow control by the duty Crude Oil Transfer Pump on start-up.

*

SET the controllers on the Electrostatic Coalescer as follows: •

Oil/Water Interface Level Controller 10-LIC-0401 to MANUAL with the Level Control Valve 10-LCV-0401 on the produced water outlet line from the vessel CLOSED

•

The power supply to the transformers for the Electrostatic Coalescer is SWITCHED OFF at the Local Control Panel

*

* 6

OPEN the 6in isolation ball valve for the cooling medium supply to the Crude Oil Cooler to REINSTATE the flow of cooling medium to the cooler. SET Temperature Controller 20-TIC-0455 to AUTO with a setpoint of 30°C to ESTABLISH the flow of cooling medium through the cooler.

7

OPEN the PSD Isolation Valve 44-XV-2017 for the heating medium outlet from the HP Crude Oil Heater to REINSTATE the flow of heating medium to the heater. SET Temperature Controller 10-TIC-0155 for the heater to MANUAL with the Temperature Control Valve 10-TCV-0155 CLOSED.


*

*

*

Page 37 / 81



5.01.6 Cold Start-up Procedure - Continued STEP

DESCRIPTION

LOCAL

PCS

8

OPEN the isolation valve 07-XV-110 to line up the Riser D2 to the HP Separator.

*

9

ENSURE there is no significant Differential Pressure (DP) across the Riser D2 ESD Valve 07-XXV-100, if necessary equalise using methanol, then OPEN this valve by RESETTING the solenoids at the Local Field Panel. The operating pressure of the subsea flowline from the Curlew Subsea Well(s) to the Riser D2 is indicated on 07-PI-102.

LOCAL RESET

*

10

ENSURE there is no significant Differential Pressure (DP) across the Riser D2 ESD Valve 07-XV-105, if necessary equalise using methanol, then OPEN this valve by RESETTING the solenoids at the Local Field Panel.

LOCAL RESET

*

11

SLOWLY OPEN the Topsides Choke 07-PCV-109 to not more than 10% initially to blow through any gas and allow pressure equalisation then FULLY OPEN the Topsides Choke 07-PCV-109.

*

Note: The topsides choke is NOT used to control the production rate from the well during the cold start-up. Well DP1 Start-up 12

CONFIRM Curlew Well DP1 Subsea Choke Valve 03-PCV-0008 is CLOSED.

*

13

OPEN Methanol Injection Valve 03-MIV-0007 to Curlew Well DP1 xmas tree upstream of Production Wing Valve 03-PWV-0006. ENSURE manifold valves 03-XV-1001/2/3 are positioned to provide an open flowpath of methanol.

*

14

START Methanol Injection Pump P-7301A, B, or C as required for injection to Curlew Well DP1 and OBSERVE the output pressures and operation to verify methanol is being injected.

*

*

Note: Operators must be in the field to observe the start of the pump. 15

ADJUST stroke length in stages slowly pressuring up the methanol piping and umbilical to the desired output.


*

Page 38 / 81


Operating Procedures 5.01.6 Cold Start-up Procedure - Continued STEP

DESCRIPTION

LOCAL

PCS

16

EQUALISE the pressure using methanol across 03-PUMV-0005 as compared from 03-PT-0015 with the last noted well CITHP.

*

17

Provide OPEN signal to 03-PUMV-0005 when the pressures are equalised.

*

Note: PWV must be shut prior to opening PUMV. *

*

18

EQUALISE the pressure using methanol to enable 03-SSSV-0011 to OPEN. Compare pressure at 03-PT-0015 with Downhole Pressure Transmitter 03-PT-0013.

19

Provide OPEN signal to 03-SSSV-0011 when the pressures are equalised.

*

20

OPEN Curlew Well DP1 Production Wing Valve 03-PWV-0006.

*

21

OPEN the Subsea Choke Valve 03-PCV-0008 for Curlew Well DP1 to 18% initially (minimal flow) to avoid exceeding the jumper design temperature (-20°C). Cold temperatures may occur initially from blowing a cold gas cap through the subsea choke. CHECK the temperature at 03-TI-0009 on the DP1 well to ensure that the well is flowing.

*

22

SLOWLY BEAN-UP the choke 03-PCV-0008 to the setting required to achieve topsides arrival temperatures above 20°C. OBSERVE the operating temperature of the well fluids arriving topsides via 07-TI-111 downstream of the topsides choke valve and continue to monitor this temperature until the flowline warms up.

*

23

Adjust Methanol Pump stroke length to set rate to 0.5 m³/h. Continue to inject Methanol at 0.5 m³/h for at least 1 hour after DP1 well startup. Ensure the topsides arrival temperature from Riser D2 is above 20°C before ceasing methanol injection to well DP1.

*

24

START chemical injection as required (referring to current Chemical Dosing Philosophy). Scale Inhibitor injection to well DP1. Corrosion inhibitor injection downstream of Riser D2 topsides choke. Demulsifier and Anti-foam injection to the inlet header for the HP separator.

*

25

MONITOR the rising operating level in the HP Separator and raise the controller setpoint gradually to an operating pressure of 38 barg.

*


Page 39 / 81



DESCRIPTION

LOCAL

PCS

26

When the oil and produced water levels are established above the trip setpoints RESET PSD Isolation Valve 10-XV-0118 for the oil outlet line.

27

SET the HP Separator Oil/Gas Interface Level Controller 10-LIC-0114 to AUTO with a setpoint of 50% and ENSURE that the partially stabilised crude oil is passed forward to the HP crude oil heater for further processing.

*

*

28

SET the HP Separator Oil/Water Interface Level Controller 10-LIC-0111 to AUTO with a setpoint of 50% and ENSURE that any produced water separated in the vessel is passed forward to the HP Separator Hydrocyclone vessel for clean-up.

*

*

29

SET the HP Crude Oil Heater Temperature Controller 10-TIC-0155 to AUTO with a setpoint initially below 70°C in order to prevent tripping on high temperatures. Gradually increase the setpoint to 70°C as conditions allow to provide further stabilisation in the downstream MP separator.

30

START Demulsifier and Anti-foam, chemical injection to inlet header for the MP separator, as required. As the crude oil has already been chemically dosed at the inlet to the HP Separator, the addition of demulsifier and anti-foam may not be necessary.

*

31

MONITOR the rising operating levels, temperature and pressure in the MP Separator and ensure that the pressure in the vessel is controlled at 7.7 barg, with excess gas passing to the HP Flare.

*

32

OPEN the 6” isolation ball valve for the heating medium supply to the MP Crude Oil Heater to REINSTATE the flow of heating medium to the heater. After establishing an initial production flow rate, SET Temperature Controller 10-TIC-0255 for the heater to MANUAL with the Temperature Control Valve 10-TCV-0255 CRACKED OPEN to establish a flow through the heater.

*

CCR

*

*

Note: The operating temperature of the MP Crude Oil Heater must be closely monitored until well fluids are passing through the heater. If the operating temperature increased above 70°C the flowrate of heating medium must be stopped to avoid tripping the heater on high high temperature. 33

RESET the Pressurisation Bypass Valve 20-XV-1202/PSD Isolation Valve 20-XV-1201 on the gas outlet line from the MP separator. These valves will OPEN in sequence to PRESSURISE the MP Compressor Suction Cooler E-2002 with gas.


CCR

Page 40 / 81



5.01.6 Cold Start-up Procedure - Continued STEP

DESCRIPTION

LOCAL

PCS CCR

34


35

SET the MP Separator Oil/Gas Interface Level Controller 10-LIC-0214 to AUTO with a setpoint of 50% and ENSURE that the crude oil is passed forward to the MP Crude Oil Heater for further processing.

*

*

36

When required, SET the MP Separator Oil/Water Interface Level Controller 10-LIC-0211 to AUTO with a setpoint of 50% and ENSURE that any produced water separated in the vessel is passed forward to the MP separator hydrocyclone vessel for further treatment.

*

*

37

SET the MP crude oil heater Temperature Controller 10-TIC-0255 to AUTO with a setpoint of 67oC. This setpoint ensures that the crude oil from the MP Separator passes through the MP crude oil heater at a satisfactory temperature to the downstream LP separator for full stabilisation.

38

MONITOR the rising operating levels and temperature in the LP Separator and ENSURE that the pressure in the vessel is controlled at 0.7 barg.

39

RESET the PSD Isolation Valve 20-XV-1221 on the gas outlet line from the LP Separator. This valve will OPEN to PRESSURISE the LP Compressor Cooler E-2003 with gas.

CCR

40

When the oil level in the LP Separator is established above the trip set point, RESET PSD Isolation Valve 10-XV-335 for the oil outlet line.

CCR

41

SET the LP Separator Oil/Gas Interface Level Controller 10-LIC-0314 to AUTO with a setpoint of 50%. The Process Value (PV) from this instrument will be used as the setpoint for the Level Control Valve 10LCV-0314 on the crude supply line from the outlet of the Export Crude Oil Cooler to the Cargo Storage Tanks.

*

42

SELECT the Crude Oil Transfer Pump P-1001A for DUTY (‘Remote Operation’ in the MAERSK FPSOS HEADQUARTERS).

CCR

43

PRIME Crude Oil Transfer Pump P-1001A selected for duty by OPENING the casing vent. CLOSE the vent valve when oil is evident at the vent. SET the Minimum Flow Controller 10-FIC-0328 to AUTO with a setpoint of 180 m3/hr (minimum flow for a single pump).


*

*

*

*

Page 41 / 81



5.01.6 Cold Start-up Procedure - Continued STEP 44

DESCRIPTION ENSURE that the Electrostatic Coalescer is lined up to receive fully stabilised crude oil from the common discharge of the crude oil transfer pumps and START P-1001A. MONITOR the crude oil transfer pump for correct operation and ENSURE the crude oil is passed forward from the pump to the Electrostatic Coalescer for further processing at 6.5 barg. Any crude oil passed through the minimum flowline is directed back to the LP Separator.

LOCAL *

PCS

Note: the pump may have to be operated in batch mode until steady operations have been achieved. CCR

45

When the produced water level in the LP Separator is established above the trip setpoint, RESET PSD Isolation Valve 10-XV-0334 for the produced water outlet line.

46

SELECT the Produced Water Transfer Pump P-1002A for DUTY (‘Remote Operation’ in the MAERSK FPSOS HEADQUARTERS). This pump will AUTO-START to direct the produced water recovered in the LP Separator back to the MP Separator for further processing once the oil/water interface level achieves the setpoint of 50%.

*

47

MONITOR the rising operating level and pressure in the Electrostatic Coalescer. When the oil level is established above the trip setpoint Shutdown Condition 10-LALL-0406 should be observed to RESET at the Local Control Panel.

*

48

49

Note: The dehydrated crude oil passes out of the Electrostatic Coalescer to the export crude oil cooler for further cooling prior to storage. Once a suitable working level of 50% has been established in the Electrostatic Coalescer SET the Oil/Water Interface Level Controller 10-LIC-0401 for the vessel to AUTO with a setpoint of 50%. Any produced water recovered in the Electrostatic Coalescer is directed to the upstream MP Crude Oil Heater for further processing. Switch on the power supply to the transformers for the Electrostatic Coalescer at the Local Control Panel.

CCR

*

*

Caution: Under no circumstances should the power supply be switched on to the transformers of the Electrostatic Coalescer until the vessel is liquid filled.


Page 42 / 81



DESCRIPTION

LOCAL

50

ENSURE that the crude oil is now being directed forward from the Electrostatic Coalescer to the Export Crude Oil Cooler for further cooling prior to storage. Once the temperature of the crude oil has been reduced to 30°C by heat exchange with cooling medium passing through the export crude oil cooler, the crude is passed forward from the Oil Processing Facilities under level control to the Crude Storage Tanks.

*

PCS

Note: If the PSD Isolation Valve 10-XV-0458 or downstream Level Control Valve 10-LCV-0314 on the crude oil supply line to the Crude Storage Tanks fail closed, the operating level in the LP separator will start to rise. If 10-XV-0458 is not reopened and the flowrate of crude to the storage tanks re-established the High High Level Trip 10-LTHH-0313 for the LP separator will be activated which in turn initiates a PSD shutdown. Note: The Curlew production is now on stream with the oil being produced but all the produced gas flared. The Gas COMPRESSION System should now be brought on line (refer to POPM Volume N41C3). 51

OPEN the Pressurisation Bypass Valve 20-XV-1052 and PSD Isolation Valve 20-XV-1051 on the gas outlet line from the HP Separator. These valves will pressurise the downstream system and divert gas from the HP Separator to the Inlet Cooler E-2001.

CCR

52

Additional Curlew well(s) can now be started to the HP separator as required.

*

Well DP2 Start-up 53


*

54

OPEN Methanol Injection Valve 03-MIV-0107 to Curlew Well DP2 xmas tree upstream of Production Wing Valve 03-PWV-0106. ENSURE manifold routing valves 03-XV-1001/2/3 provide an open flowpath.

*


Page 43 / 81


Operating Procedures 5.01.6 Cold Start-up Production - Continued STEP

DESCRIPTION

LOCAL

PCS

55

START Subsea Methanol Injection Pump P-7301A, B, or C as required for injection to Curlew Well DP2 and OBSERVE the output pressures and operation and flow to verify methanol is being injected.

*

*



*

57

EQUALISE the pressure across 03-PUMV-0105 as compared at 03PT-0115 with the last noted well CITHP.

*

58


*


*

59

EQUALISE the pressure using methanol to enable 03-SSSV-0111 to OPEN. Compare pressure at 03-PT-0115 with Downhole Pressure Transmitter 03-PT-0113.

60


*

61


*

62


*

63

Adjust Methanol Pump stroke length to set rate to 0.5m³/h. Continue to inject Methanol at a rate of 0.5m³/h for 1 hour after DP2 well startup. After 1 hour and provided the topsides arrival temperature is still above 20°C methanol injection to Curlew Well DP2 can be ceased.

*


Page 44 / 81



DESCRIPTION

LOCAL

PCS

64

CLOSE Methanol Injection Valve 03-MIV-0107 to Curlew Well DP2 xmas tree upstream of Production Wing Valve 03-PWV-0106.

65

ENSURE there is no significant Differential Pressure (DP) across the Riser D1 ESD Valve 07-XXV-200, if necessary equalise using methanol, then OPEN this valve by RESETTING the solenoids at the Local Field Panel. The operating pressure of the subsea flowline from the Curlew Subsea Well(s) to the Riser D1 is indicated on 07-PI-202.

LOCAL RESET

*

66

ENSURE there is no significant DP across the Riser D1 ESD Valve 07-XV-205 then OPEN this valve by RESETTING the solenoids at the Local Field Panel.

LOCAL RESET

*

67

OPEN the Production Manifold Diverter Valve 07-XV-210 for Riser D1 to line-up to the HP Separator.

*

68

SLOWLY OPEN the Riser D1 Topsides Choke 07-PCV-209 to commence flow up Riser D1 and cutback on Riser D2 Choke 07PCV-109 in order to flow up both risers. Continue to FULLY OPEN both chokes once flows are even.

*

*



*

70

OPEN Methanol Injection Valve 03-MIV-1107 to Curlew Well DP4 xmas tree upstream of Production Wing Valve 03-PWV-1106. ENSURE manifold valves 03-XV-1001/2/3 are positioned to provide an open flowpath of methanol.

*

71


*

*




*

Page 45 / 81



5.01.6 Cold Start-up Procedure – Continued STEP 73

74

DESCRIPTION EQUALISE the pressure using methanol across 03-PUMV-1105 as compared at 03-PT-1115 with the last noted well CITHP.

LOCAL

OPEN 03-PUMV-1105 when the pressures are equalised.

PCS *

*

Note: PWV must be shut prior to opening PUMV. 75

OPEN 03-SSSV-1111 (valve is self-equalising on well DP4). If it doesn’t open then inject methanol to equalise pressure across the valve.

*

76


*

77

SLOWLY OPEN the DP4 subsea choke valve 03-PCV-1108 to a choke setting of 12% to establish a very low flowrate of well fluids from Well DP4. Once the FTHP falls below 85 barg then the choke can be opened to 15%.

*

78

OBSERVE the temperature of the DP4 well fluids downstream of the choke on 03-TT-1122 and monitor until the well warms up.

*

79

Adjust Methanol Pump stroke length to set rate to 0.5m³/h. Continue to inject Methanol at a rate of 0.5m³/h for 1 hour after DP4 well start-up. Ensure the topsides arrival temperature from both Risers is above 20°C and the temperature downstream of the DP4 choke is above 22°C before ceasing methanol injection to Well DP4.

*



*

82

OPEN Methanol Injection Valve 03-MIV-0307 to Curlew Well DP3 xmas tree upstream of Production Wing Valve 03-PWV-0306. ENSURE manifold routing valves 03-XV-1001/2/3 provide an open flowpath.

*

83


*

*

Note: Operators must be in the field to observe the start of the pump.


Page 46 / 81



5.01.6 Cold Start-up Procedure - Continued STEP 84

DESCRIPTION ADJUST stroke length in stages slowly pressuring up the methanol piping and umbilical to the desired output.

LOCAL *

PCS

85

EQUALISE the pressure using methanol across 03-PUMV-0305 as compared at 03-PT-0315 with the last noted well CITHP.

*

86


*

Note: PWV must be shut prior to opening PUMV. 87

EQUALISE pressure to enable 03-SSSV-1111 to OPEN. Compare pressure at 03-PT-0315 with Downhole Pressure Transmitter 03PT-0313.

*

88


*

89


*

90


*

91

OBSERVE the operating temperature of the well fluids via tree sensor 03-TT-0309 and Riser D1 sensor 07-TT-211 and continue to monitor these temperatures until the well warms up.

*

92

Adjust Methanol Pump stroke length to set rate to 0.5m³/h. Continue to inject Methanol at a rate of 0.5m³/h for at least 1hour after DP3 well start-up. Provided topsides arrival temperature from both Risers is above 20°C then cease methanol injection to Well DP3.

*

93

BEAN-UP Curlew D wells to desired rates by following Production Technologist’s latest Bean-up Procedure.

*

94

The chemical injection rates for all chemicals directed to the Oil Processing Facilities can now be SET to their optimum rate to conserve chemicals.


*

Page 47 / 81



DESCRIPTION

LOCAL

PCS

Well BP1 Start-up 95

RESET the PSD Isolation Valve 20-XV-1191 on the gas outlet line from the Test separator.

96

SLOWLY OPEN the 10in isolation ball valve on the gas outlet line from the Test separator to the Inlet Cooler E-2201.

97


CCR

*

CCR

Note: All PSD isolation valves must be correctly identified in the Valve Checklists included in the Tables in Part 5 of this book BEFORE the valves are reset to the open position. 98

SET the Test separator Oil/Gas Interface Level Controller 10-LIC-0514 to AUTO with a setpoint of 50% and ENSURE that the crude oil is passed forward to the MP separator for further processing.

*

*

99

SET the Test separator Oil/Water Interface Level Controller 10-LIC-0511 to AUTO with a setpoint of 50% and ENSURE that any produced water separated in the vessel is passed forward to the Test separator hydrocyclone vessel for further treatment.

*

*

100

Ensure the Test separator is depressurised to minimum pressure for starting well BP1 to facilitate flowing of the well

*

101

The field production routing keyswitch is positioned at 76-XS-1000A in order to confirm that Curlew B is produced to the Test separator.

*

102

ENSURE there is no significant DP across the Curlew BP1 Flowline ESD Valve 07-XV-305 then OPEN this valve by RESETTING the solenoids at the Local Field Panel.

LOCAL RESET

103

OPEN the Test Manifold Diverter Valve 07-XV-404 for Curlew BP1 riser to line-up this well to the Test manifold.

*

*

Note: The Curlew BP-1 Riser is now isolated from the Test separator by the Topsides Choke Valve 07-PCV-309.


Page 48 / 81


Operating Procedures 5.01.6 Cold Start-up Procedure – Continued STEP 104

DESCRIPTION SET the controllers for the Test separator as follows: •

LOCAL

Vessel Pressure Controller 10-PIC-0507B to AUTO with a setpoint of 10 barg.

*

CCR

•The produced water routing keyswitch is positioned at 40-HS-4000A in order to align the Test separator Hydrocyclone to the Test separator •

•

PCS

Oil/water Interface Level Controller 10-LIC-0511 to MANUAL with the Level Control Valve 10-LCV-0511 positioned on the clean water outlet from the Test separator hydrocyclone CLOSED. Any produced water separated in the Test separator is routed to the Test separator hydrocyclone for further processing on start-up

*


*

105


*

106

EQUALISE the pressure across 03-PUMV-0205 as compared from 03-PT-0215 with the last noted well CITHP.

*

107


*


*

108

EQUALISE pressure to enable 03-SSSV-0211 to OPEN. Compare pressure at 03-PT-0215 with Downhole Pressure Transmitter 03-PT0213.

109


*

110

FULLY OPEN the Subsea Choke Valve 03-PCV-0208 for Curlew Well BP1.

*

111

OPEN Curlew Well BP1 Production Wing Valve 03-PWV-0206. MONITOR BP1 wellhead temperature at 03-TT-0209 to ensure the well is flowing.

*

112

RETURN the Subsea Choke Valve 03-PCV-0208 for Curlew Well BP1 to 50% once the FWT has reached 40 – 50°C.

*


Page 49 / 81



DESCRIPTION

LOCAL

PCS

113

Adjust Methanol Pump stroke length to set rate to 0.5m³/h. Continue to inject Methanol at a rate of 0.5m³/h for at least 1 hour after BP1 well start-up. Ensure the topsides arrival temperature from Riser B1 is above 20°C before ceasing methanol injection to well BP1.

*

*

114

OBSERVE the operating temperature of the well fluids arriving topsides via 07-TI-311 downstream of the topsides choke valve and continue to monitor this temperature until the flowline warms up.

115

Once the topsides arrival temperature has reached 20°C the Test Separator pressure can be steadily increased to desired pressure on 10-PIC-507B.


*

*

Page 50 / 81



5.02 Hot Start-up of the Oil Processing Facilities 5.02.1 Preamble

This procedure assumes that the oil processing facilities have been operating normally but have shutdown either manually for a short period of time or as a result of a Production Stop or Process Trip. The procedure assumes that the reason for the shutdown has been rectified and it is considered safe to re-start the facilities and resume the transfer of fully stabilised crude to the cargo storage tanks. Is assumed for the purposes of this procedure that the subsea flowlines to the FPSO are pressurised and have not cooled down below the hydrate temperature. All the production separators are still pressurised but there is no forward flow of crude oil, produced water or process gas. The levels, temperatures and pressures of all the vessels within the oil processing facilities are at or near their normal operating levels. The crude oil transfer pump and produced water transfer pump in service have shut down. The hot start-up procedure of the oil processing facilities can be summarised in the following major steps: • •

Verify set points/operational modes of process controllers Reset the shutdown valves on the outlets from the vessels and suction lines for any pumps

•

Restart the duty crude oil transfer pump

•

Restart Produced Water Pumps P-1002A/B


Page 51 / 81




•

Re-establish flow from the Curlew Subsea Wells DP1, DP2, DP3 and DP4 to the HP separator to re-introduce gas to the Fuel Gas System and resume the forward flow of crude oil through Oil Processing Facilities

•

Re-establish flow from the Curlew Subsea Well BP1 to the Test separator, if required.

•

Restart chemical injection to the oil processing facilities

This hot start-up procedure must be read in conjunction with the hot start-up procedures of the following systems: •

Volume 1 Book A - Subsea Facilities

•

Volume 1 Book C - Gas Processing Facilities

•

Volume 1 Book D - Produced Water Facilities

•

Volume 1 Book K - Fuel Gas System

•

Volume 1 Book M - Chemical Injection

The hot start-up procedure of the oil processing facilities assumes that the gas compression facilities are prepared to receive process gas from the separation vessels and the produced water treatment package is available to process the produced water from the system.


Page 52 / 81




WARNING: ALL SYSTEM PRESSURE SAFETY RELIEF VALVES MUST BE LINED UP FOR NORMAL OPERATION. (1)

No Permits to Work or electrical isolations are in force which may prohibit system start-up.

(2)

The Fire and Gas Detection/Protection, Process Control System (PCS) and Safety Related Systems (PSDs) are operational along with the alarms, trips and controllers.

(3)

It is assumed that in a short duration shutdown, it is unlikely that spades or blinds would be moved, or drain and vent valves opened, unless to take corrective action on the cause of shutdown. It is therefore unnecessary to recheck these items other than if they have been disturbed.

(4)

All instrument and level bridle drain valves are closed.

(5)

All instrument isolation valves are open.

(6)

Ensure the Inlet Cooler E-2201, MP Compressor Suction Cooler E-2002 and LP Compressor Cooler E-2003 in the Gas Processing Facilities are prepared to receive the process gas from the HP, MP and LP separators.

(7)

Ensure Glycol Circulation has been initiated and the glycol is up to temperature in the Gas Dehydration System.

(8)

The following utility systems are available: • Electrical Power Distribution (including trace heating) • Instrument Air • Heating Medium • Cooling Medium • Cooling Seawater • Chemical Injection Package including the availability of the following chemicals as required: -

Methanol

-

Demulsifier

-

Anti-foam


Scale Inhibitor Page 53 / 81



5.02.2 Preconditions- Continued

-

Corrosion Inhibitor

-

Wax Inhibitor

-

HP Flare System

-

LP Flare System

-

Hazardous Open Drains

(9)

Communications have been established with all the personnel involved.

(10)

All HVAC and Turret Annulus Fans have been restarted.


Page 54 / 81



5.02.3 Hot Start-up PSD Valve Checklist

Refer to Figures 3.01 to 3.03 in Section 3 of this Volume and the P&IDs identified below. (1)

The System Operator should CHECK the following valves to confirm the valve settings are as given below.

(2)

Where the valves are found to be out of position, the operator should satisfy himself that it is safe to move the valves before doing so.

Hot Start-up PSD Valve Checklist Valve Tag

Valve Description

Setting

Subsea Production Wells (P&ID Drawing Nos CUR-MAS-PB-20021-001 to 004)

03-AWV0004/0104/0304/ 1104/0204

Annulus Master Valve (Curlew Wells DP1/DP2/DP3/DP4/BP1)

03-AXOV0001/0101/0301/ 1101/0201

Annulus Crossover Valve (Curlew Wells DP1/DP2/DP3/DP4/BP1)

CLOSED

03-SSSV0011/0111/0311/ 1111/0211

Subsurface Safety Valve (Curlew Wells DP1/DP2/DP3/DP4/BP1)

OPEN

03-PUMV0005/0105/0305/ 1105/0205

Production Upper Master Valve (Curlew Wells DP1/DP2/DP3/DP4/BP1)

OPEN

03-PWV0006/0106/0306/ 1106/0206

Production Wing Valve (Curlew Wells DP1/DP2/DP4/BP1)

CLOSED

03-PCV0008/0108/0308/ 1108/0208

Production Choke Valve (Curlew Wells DP1/DP2/DP3/DP4/BP1)

CLOSED

03-MIV0007/0107/0307/ 1107/0207

Methanol Injection Valve (Curlew Wells DP1/DP2/DP3/DP4/BP1)

OPEN


OPEN

Page 55 / 81



Valve Description

Setting

03-PTIV0010/0110/0310/ 1110/0210

Production Test Isolation Valve (Curlew Wells DP1/DP2/DP3/DP4/BP1)

CLOSED

Curlew D Production Manifold & SDU (P&ID Drawing No MAERSK DRILLING AUSTRALIA-CP692-U0002-001 Rev C1) 03-XV-1001


OPEN

03-XV-1002


OPEN

03-XV-1003

Crossover Isolation Valve

OPEN

Spare Production Flowline (P&ID Drawing No CUR-MAS-TP-42035-001)) 07-XXV-0500

Spare Flowline Riser ESD Valve

CLOSED

07-XV-0505

Spare Flowline ESD Valve

CLOSED

07-XV-0510

12in Spare Flowline Integrated DB&B Isolation Valve

CLOSED

Spare Flowline Topsides Choke Valve

CLOSED

07-PCV-0509

Curlew Production Flowlines (P&ID Drawing No CUR-MAS-TP-42002-001) 07-XXV-100

Curlew Well D2 Riser PSD Valve

CLOSED

D2 Flowline ESD Valve

CLOSED

Choke Valve D2

CLOSED

07-XV-110

D2 Diverter Valve to the HP Separator

CLOSED

07-XV-402

D2 Diverter Valve to the Test Manifold

OPEN

Curlew D1 Riser PSD Valve

CLOSED

D1 Flowline ESD Valve

CLOSED

Choke Valve D1

CLOSED

07-XV-105 07-PCV-109

07-XXV-200 07-XV-205 07-PCV-209


Page 56 / 81



Valve Description

Setting

07-XV-210

D1 Diverter Valve to the HP Separator

OPEN

07-XV-403

D1 Diverter Valve to the Test Manifold

CLOSED

Curlew B1 Riser PSD Valve

CLOSED

B1 Riser ESD Valve

CLOSED

Topsides Choke Valve Riser B1

CLOSED

07-XV-310

Riser B1 Diverter Valve to the MP Separator

CLOSED

07-XV-404

Riser B1 Diverter Valve to the Test Manifold

OPEN

07-XXV-300 07-XV-305 07-PCV-309

Test Separator (P&ID Drawing Nos CUR- MAS-PM-20048-501 and CUR-MAS-PB-20048-002) 10-XV-0501

Blowdown Valve to HP Flare

CLOSED

20-XV-1191

PSD Isolation Valve for gas outlet from Test separator

CLOSED

10-XV-0518

PSD Isolation Valve for crude outlet from Test separator

CLOSED

HP Separator (P&ID Drawing Nos CUR-MAS-PM-20041-501 and CUR-MAS-PB-20041-002) 10-XV-0101

Blowdown Valve to HP Flare

CLOSED

22-XV-1051

PSD Isolation Valve for gas outlet from HP separator

CLOSED

22-XV-1052

Pressurisation Bypass Valve for gas outlet from HP separator

CLOSED

10-XV-0118

PSD Isolation Valve on the crude outlet from HP separator

CLOSED

HP Crude Oil Heater (P&ID Drawing No CUR-MAS-PM-20042-501) 44-XV-2017

PSD Isolation Valve on heating medium return from the HP crude oil heater


CLOSED

Page 57 / 81



Valve Description

Setting

MP Separator (P&ID Drawing Nos CUR-MAS-PM-20043-501 and CUR-MAS-PB-20043-002) 10-XV-0201

Blowdown Valve to LP Flare

CLOSED

20-XV-1201

PSD Isolation Valve for gas outlet from MP separator

CLOSED

20-XV-1202

Pressurisation Bypass Valve for gas outlet from MP separator

CLOSED

10-XV-0218

PSD Isolation Valve on the crude outlet from MP separator

CLOSED

LP Separator (P&ID Drawing Nos CUR-MAS-PM-20045-501 and CUR-MAS-PB-20045-002) 10-XV-0301

Blowdown Valve to LP Flare

CLOSED

20-XV-1221

PSD Isolation Valve for gas outlet from LP separator

CLOSED

10-XV-0335

PSD Isolation Valve for crude outlet from LP separator

CLOSED

10-XV-0334

PSD Isolation Valve for produced water outlet from LP separator

CLOSED

Crude Transfer and Cooling (P&ID Drawing No CUR-MAS-PM-20047-501) 10-XV-0458

PSD Isolation Valve for the crude outlet from the export crude oil cooler to storage


CLOSED

Page 58 / 81



5.02.4 Hot Start-up Overrides

During the hot start-up of the Oil Processing Facilities there are no inputs to the Shutdown System which require to be overridden at the shutdown panel until steady operating conditions have been achieved.


Page 59 / 81


Operating Procedures 5.02.5 Hot Start-up Procedure STEP

DESCRIPTION

LOCAL

PCS

Refer to Figures 3.01 to 3.03 in Section 3 of this Volume while reading the following procedure. 1

ENSURE that all inputs to the Shutdown System are healthy when RESETTING the PSD isolation valves identified in Steps 2 to 6.

CCR

2

On the HP separator RESET the Gas Outlet PSD Isolation Valve 22XV-1051, Oil Outlet PSD Isolation Valve 10-XV-0118 and ENSURE that the controllers are SET as follows:

CCR

•

Vessel Pressure Controller 10-PIC-0107 to AUTO with a setpoint of 38barg

*

•

Oil/Water Interface Level Controller 10-LIC-0111 to AUTO with a setpoint of 50%

*

•

Oil/Gas Interface Level Controller 10-LIC-0114 to AUTO with a setpoint of 50%

*

Note: If the operating levels in the HP separator are high, the level controllers may initially require to be SET in MANUAL with zero output (ie level control valves fully closed). This is to allow the operating levels in the vessel to be slowly reduced by opening the controllers in Manual. 3

On the HP crude oil heater RESET the Heating Medium Outlet PSD Isolation Valve 44-XV-2017, RE-ESTABLISH a flowrate of heating medium through the heater and ENSURE that the Temperature Controller 10-TIC-0155 is SET to AUTO with a setpoint of 70°C.

*

CCR

Note: Depending on the production throughput and fluid arrival temperature, the set point should be set as high as possible within the limit of the Heater rating. The outlet temperature anticipated at the production profile, at full heater design duty is expected to vary in the range of 54 to 71°C. The alarm trip points can be reset based on operating experience.


Page 60 / 81


Operating Procedures 5.02.5 Hot Start-up Procedure - Continued STEP

DESCRIPTION

4

On the MP separator RESET the Gas Outlet PSD Isolation Valve 20XV-1201 and Oil Outlet PSD Isolation Valve 10-XV-0218 and ENSURE that the controllers are SET as follows:

LOCAL

PCS CCR

•

Vessel Pressure Controller 10-PIC-0207 to AUTO with a setpoint of 7 barg

*

•


*

•


*

Note: If the operating levels in the MP separator are high, the level controllers may initially require to be SET in MANUAL with zero output (ie level control valves fully closed). This is to allow the operating levels in the vessel to be slowly reduced by opening the controllers in Manual. 5

On the MP crude oil heater ENSURE that the Temperature Controller 10-TIC-0255 is SET to AUTO with a setpoint of 67oC. A flowrate of heating medium will RE-ESTABLISH itself through the MP crude oil heater once the partially stabilised crude oil from the upstream MP Separator is directed through the heater.

6

On the LP separator RESET the Gas Outlet PSD Isolation Valve 20XV-1221, Oil Outlet PSD Isolation Valve 10-XV-0335 and Produced Water Outlet Valve 10-XV-0334 and ENSURE that the controllers are SET as follows:

*

CCR

CCR

*

•

Vessel Pressure Controller 10-PIC-0307 to AUTO with a setpoint of 1.1 barg

•


*

•


*

Note: If the oil/water interface level in the LP separator is high, set the pumps to manual and stop from the CCR. This is to prevent the duty produced water transfer pump from AUTO-STARTING before forward flow through the Oil Processing Facilities has recommenced.


Page 61 / 81



DESCRIPTION

LOCAL

PCS

7

On the Electrostatic Coalescer ENSURE that the Oil/Water Interface Level Controller 10-LIC-0401 is SET to AUTO with a setpoint of 50%.

*

CCR*

*

*

CAUTION: ENSURE THAT VAPOUR BREAKOUT DOES NOT OCCUR IN THE ELECTROSTATIC COALESCER AND THE VESSEL REMAINS FULL OF LIQUID. THE VENT VALVES FROM THE COALESCER BUSHINGS TO THE OIL OUTLET LINE FROM THE VESSEL MUST REMAIN IN THE OPEN POSITION. 8

ENSURE the flowrate of cooling medium to the export crude oil cooler is uninterrupted and the Temperature Controller 20-TIC-0455 for the cooler is SET to AUTO with a setpoint of 30oC.

9

ENSURE that the appropriate cargo oil tanks are lined up to receive fully stabilised crude oil from the oil processing facilities once production re-commences.

*

10

ENSURE that the Minimum Flow Controller 10-FIC-032B for the Crude Oil Transfer Pumps P-1001A/B is SET to AUTO with a setpoint of 180 m3/hr. (single pump setting)

*

11

RE-START the duty Crude Oil Transfer Pump P-1001A to RE-ESTABLISH the flow of fully stabilised crude oil from the LP separator to the electrostatic coalescer.

*

Note: Until the forward flow of crude oil is re-established through the oil processing facilities it is probable the duty crude oil transfer pump will operate on full recycle. However, the pump may have to be operated in manual – batch dumping until continuous flow has been established. 12

RESTART the power supply to the electrodes of the electrostatic coalescer by operating the reset button on the local control panel.

*

13

Ensure that the Curlew Riser D2 topside choke valve 07-PCV-0109 is in the closed position.

*

Caution: To avoid the risk of overpressurising the production separator with a large gas blowby under the well CITHP condition, the riser valve should not be opened without first ensuring that the choke valve is in the closed position first.


Page 62 / 81



DESCRIPTION

LOCAL

14

ENSURE there is no significant DP across Curlew D2 Riser ESD Valve 07-XXV-100, if necessary equalise using methanol, then REOPEN this valve by RESETTING the solenoids at the Local Field Panel.

LOCAL RESET

15

ENSURE there is no significant DP across the Curlew D2 Flowline ESD Valve 07-XV-105 then OPEN this valve by RESETTING the solenoids at the Local Field Panel.

PCS

*

Note: The well fluids from the Curlew Riser D2 subsea flowline are now isolated from the HP separator by the Topsides Choke Valve 07-PCV-0109. 16

RE-OPEN Topsides Choke Valve 07-PCV-0109 choke. This action will RE-INTRODUCE well fluids from the flowline to the HP separator.

*

Note: The 8in choke valve should be stepped up carefully in small increments of 5% in order to avoid the risk of overpressuring the HP Separator. It should only be opened above 30% when the pipeline pressure drops below 100barg. 17

If the DP1 wellhead temperature has fallen below 20°C then OPEN Methanol Injection Valve 03-MIV-0007 to Curlew Well DP1 xmas tree upstream of 03-PWV-0006. ENSURE manifold valves 03-XV-1001/2/3 are positioned to provide an open flowpath of methanol.

*

18

START Methanol injection to Well DP1 and OBSERVE the output pressures and operation.

*

19

REOPEN 03-PWV-0006 for Curlew well DP1 at the xmas tree.

*

20

SLOWLY OPEN Subsea Choke Valve 03-PCV-0008 for Curlew Well DP1 to its original setting to RE-ESTABLISH flow from the well.

*


*

Page 63 / 81



DESCRIPTION

LOCAL

21

If the DP2 wellhead temperature has fallen below 20°C then OPEN Methanol Injection Valve 03-MIV-0107 and CLOSE DP1 Methanol Injection Valve 03-MIV-0007.

22

REOPEN 03-PWV-0106 for Curlew well DP2 at the xmas tree, then slowly open Subsea Choke Valve 03-PCV-0108 for Curlew Well DP2 to its original setting to RE-ESTABLISH flow from the well.

23

OBSERVE arrival temperature topsides at 07-TT-104 and cease Methanol injection if temperature is above 20°C.

*

24

As the well fluids arrive at the FPSO the forward flow of crude oil from the HP separator will recommence. Once the operating levels, temperatures and pressures of the equipment in the downstream processing facilities returns to normal set the pumps to AUTO from the CCR. This is to allow the duty produced water transfer pump to AUTO-START to control the oil/water interface level in the LP separator.

*

PCS

*

*

Note: As the forward flow of fully stabilised crude oil from the plant increases the Level Control Valve 10-LCV-0314 for the LP separator will progressively OPEN to INCREASE the flowrate of dead crude to the Cargo Storage Tanks. 25

RESTART the following chemical injection facilities, as required: •

Scale Inhibitor at wellheads and Corrosion Inhibitor topsides

•

Demulsifier and Anti-foam to the crude inlet of the HP, Test and MP separators

*

*

26

ENSURE there is no significant DP across the Curlew D1 riser ESD Valve 07-XV-205 and 07-XXV-200 then OPEN these valves by RESETTING the solenoids at the Local Field Panel.

27

SLOWLY OPEN the Topsides Choke 07-PCV-209 for Curlew D1 Riser until fully open.


LOCAL RESET

*

*

Page 64 / 81



DESCRIPTION

28


29

If the temperature downstream of the DP4 choke, as measured on 03-TT-1122, has fallen below 22°C then START Methanol injection to Well DP4 and OBSERVE the output pressures and operation.

30


31

STOP the methanol injection to well DP4 when temperature downstream of the DP4 choke is above 22°C.

32


33

If the DP3 wellhead temperature has fallen below 20°C then START Methanol injection to Well DP3 and OBSERVE the output pressures and operation.

34


35

STOP the methanol pump when arrival temperatures from D1 and D2 flowlines are above 20°C.

36

In order to route Curlew B1 to the Test Separator, RESET the Gas Outlet PSD Isolation Valve 20-XV-1191, Oil Outlet PSD Isolation Valve 10-XV-0518 and Produced Water Outlet PSD Isolation Valve 10-XV-0520 and ENSURE that the controllers are SET as follows: •

Vessel Pressure Controller 10-PIC-0507 to AUTO with a minimal setpoint below 2bar in order to facilitate flowing the Curlew B well

•


•



LOCAL

PCS *

*

*

*

*

*

*

*

*

*

*

Page 65 / 81


Operating Procedures 5.02.5 Hot Start-up Procedure - Continued

37

ENSURE there is no significant DP across Curlew B1 Riser ESD Valve 07-XV-300 then OPEN this valve by RESETTING the solenoids at the Local Field Panel

38

ENSURE there is no significant DP across the Curlew B1 Flowline ESD Valve 07-XV-305 then OPEN this valve by RESETTING the solenoids at the Local Field Panel.

LOCAL RESET

*

*

Note: The Curlew B1 Riser is now isolated from the Test separator by the Topsides Choke Valve 07-PCV-309. 39

SLOWLY OPEN the Topsides Choke 07-PCV-309 for Curlew BP-1 Riser until fully open.

*

40

If the BP1 wellhead temperature has fallen below 20°C then START Methanol injection to Well BP1 and OBSERVE the output pressures and operation.

41

FULLY OPEN the Subsea Choke Valve 03-PCV-0208 for Curlew Well BP1.

*

42

REOPEN 03-PWV-0206 for Curlew well BP1 at the xmas tree to re-establish flow from the well.

*

43

STOP the methanol pump to Curlew well BP1 when Curlew B1 Flowline arrival temperatures are above 20°C as measured on 07TT-304.

44

RETURN the Subsea Choke Valve 03-PCV-0208 for Curlew Well BP1 to 50% once the FWT has reached 40 – 50°C.

*

*

*

Note: If the well fails to flow immediately, leave the well open to the Test separator until advised to shut in by Production engineering. 45

RESTART the following chemical injection facilities, as required: •

Scale Inhibitor at BP1 wellhead and Corrosion Inhibitor topsides

•

Demulsifier and Anti-foam to the crude inlet of the Test separator


*

*

Page 66 / 81



5.03 Normal Running

Under normal operating conditions the oil processing facilities are automatically controlled via the PCS with minimal field operator intervention. However, the following checks should be carried out periodically to ensure that all system equipment is operated within the desired parameters.

Operational Checks

Check all levels, pressures and temperatures throughout the system. The Field Operator should regularly line walk the system to visually inspect for leaks, damage, and any system abnormality. Report any leaks, malfunctions or irregular operating occurrences to the Shift Supervisor immediately. The Field Operator should regularly liaise with the control room operator to cross check the accuracy of the instrumentation, ie the comparison between the local level gauge and the transmitted level at the PCS. Where necessary, blowdown the instruments via their impulse lines. Note: The blowdown of instruments must be a controlled operation when hydrocarbon gases are concerned. Visually inspect the condition of the equipment and pipework for corrosion. Excessive corrosion must be reported to supervision. Visually inspect the condition of the key operated interlocks for the pressure safety relief valves included in the system. Protect against the weather with grease or other weather proofing materials. Check the chemical injection rates are correctly set for the flowrates through the oil processing facilities and the rates as necessary. If production rates up both Curlew D risers does not achieve arrival temperatures that exceed the wax appearance temperature of 35°C then Curlew D should be changed to single riser production, However, commingling flow via both flowlines hydraulically unconstrains Curlew D production as FTHP’s decline. Monitor well arrival temperatures to check if wax inhibitor injection becomes a requirement. Routinely monitor for wax deposits through recording pipeline pressure drop at various rates. Check the inventory of the following chemical stocks: • Methanol • Demulsifier • Anti-foam • Scale Inhibitor • Corrosion Inhibitor • Wax Inhibitor


Page 67 / 81


Operating Procedures 5.03 Normal Running Continued

Shift operator log books are to contain sufficient detail of the plant status including any deviation from the norm such as well alignment or vessel isolations, in particular isolations to any protective equipment. Off-going shift operators are to ensure that the oncoming shift operators are full briefed on the status of the plant as detailed in the log book. Both the off-going and oncoming shift operators must sign the Area Log Book before shift responsibility is handed over.

Test/HP/MP Separators

HP/MP Crude Oil Heaters

LP Separator

(1)

Monitor the operation of the separators, ensuring that the automatic pressure and level control systems are maintaining the operating conditions of the vessels at the desired values.

(2)

Check the water in oil concentration of the crude outlet from the test, HP and MP separators. If the three-phase separation process in these vessels is working efficiently the water in oil concentration should not exceed 5.0% (volume).

(3)

Check the oil in water concentration of the produced water from the test, HP and LP separators. If the three phase separation process in these vessels is working efficiently the oil in water concentration should not exceed 200 to 300PPM.

(1)

Monitor the operation of the heaters, ensuring that the automatic temperature control systems are maintaining the temperature of the incoming crude at the desired temperature of 75oC for the HP crude oil heater and 67oC for the MP crude oil heater.

(2)

Check the pressure of the heating medium supply to and return from the heaters. Low pressures for the heating medium supply and return are indicative of a heating medium distribution fault and not a problem with the crude oil heaters.

(1)

Monitor the operation of the LP separator, ensuring that the automatic pressure and level control systems are maintaining the operating conditions of the vessels at the desired values.

(2)

Ensure that the duty produced water transfer pump auto-starts on demand to control the oil/water interface level in the LP separator.


Page 68 / 81



5.03 Normal Running Continued Produced Water/Crude Oil Transfer Pumps

(1)

Check the pump suction and discharge pressure readings are normal by observing the local pressure gauges on the suction and discharge lines.

(2)

Check all joints, valve glands and mechanical seals for leaks.

(3)

Check the pumpset for unusual/excessive noise or vibration.

Electrostatic Coalescer

(1)

Check the local control panel and investigate alarm or trip conditions.

Export Crude Oil Cooler

(1)

Monitor the operation of the export crude oil cooler, ensuring that the automatic temperature control system is maintaining the stabilised crude exiting the cooler at the desired temperature of 30oC.

(2)

Check the pressure of the cooling medium supply to and return from the cooler. Low operating pressures for the cooling medium supply and return are indicative of a cooling seawater distribution fault and not a problem with the crude oil cooler internals.

(1)

Check single riser production is sufficient for the target production rate by referring to the chart below. The chart provides capacity liquid and gas rate for a particular flowing tubing head pressure. Optimise oil rate up single riser from Curlew D wells by using selected well choke settings as advised by Production Dept.

Curlew D Single Flowline Capacity


Page 69 / 81


Operating Procedures 5.04 Planned Shutdown of the Oil Processing Facilities 5.04.1 Preamble

The following planned shutdown procedure describes the shutdown of the oil processing facilities as part of an overall shutdown of the FPSO processing facilities in preparation for major inspection/maintenance activities that are described in Section 6 of this Volume. The planned shutdown procedure for the Oil Processing Facilities can be summarised in the following major steps: •

Commence Methanol injection to the subsea production facilities. This is to protect the entire length of the flowlines from hydrate formation once production has stopped

•

Reduce the flowrate of well fluids from the Curlew D and B reservoirs by progressively shutting in the wells

•

Direct the decreasing flowrate of crude oil to the selected Crude Oil Storage Tanks

•

Depressurise all flowlines to the separation vessels in the oil processing facilities

•

Flush the crude inventories of the separation vessels to the crude storage tanks using the jetting facilities and deaerated seawater

• •

•

Shutdown the Electrostatic Coalescer Shutdown the duty Crude Oil Transfer Pump and Produced Water Return Pump Reduce the liquid levels in the separation vessels to LALL.

•

Depressurise the separation vessels in the oil processing facilities

•

Shut in and drain the heating and cooling medium from the heaters and crude oil cooler


Page 70 / 81




(1)

No Permits to Work or electrical isolations are in force which may prohibit the shutdown of the Oil Processing Facilities.

(2)

The Fire and Gas Detection/Protection, Distributed Control System (DCS), Safety Related Systems (PSDs) are operational along with the alarms, trips, and controllers.

(3)

Safety meetings have been held with all directly and indirectly concerned parties, outlining the workscope and procedures.

Note: All drainings from the oil processing facilities must be directed to the Hazardous Area Open Drains which are suitable for disposing of liquid hydrocarbons. (4)

Communications have been established between the personnel involved in this procedure.


Page 71 / 81


Operating Procedures 5.04.3 Planned Shutdown Procedure STEP

DESCRIPTION

LOCAL

PCS

1

COMMENCE methanol injection to the xmas trees for the Curlew D production wells. In order to ensure the flowlines are inhibited methanol injection must continue for at least a 2-hour period and at a rate of approximately 1.2m³/h prior to shutting in the wells. Each well that has been in operation should have methanol injected to it for at least half an hour in turn.

*

*

Note: Time to dose the flowlines will depend on production rates and must ensure the whole flowline and riser is inhibited. 2

COMMENCE methanol injection to the BP1 xmas tree to inhibit the Curlew B flowline. Methanol injection must continue for at least 1-hour and at a rate of approximately 1.2m³/h prior to shutting the well. Note: Time to dose the flowlines will depend on production rates and must ensure the whole flowline and riser is inhibited.

3

SHUT DOWN all chemical injection pumps lined up to the Oil Processing Facilities.

4

PROGRESSIVELY CLOSE the Subsea Choke Valves for the Curlew production wells.

5

CLOSE the Tree Valves for the Curlew production wells: PWV, PUMV, SSSV and then MIV, CIVs.

*

*

The following shutdown steps may also be implemented at the discretion of the Production Supervisor. These relate to shutdown of the rest of the oil processing facilities. 6

Once all forward flow of well fluids through the swivel stack has ceased, the Leak Recuperation System must be SHUT DOWN. Details on how to operate these facilities are provided in Sections 4 and 5 of Operating Procedures Manual Volume 1 Book A - Subsea Facilities.

*

7

ENSURE that the Crude Oil Transfer Pump in service is operating on FULL RECYCLE once all forward flow through the Oil Processing Facilities ceases.

*


*

Page 72 / 81


Operating Procedures 5.04.3 Planned Shutdown Procedure - Continued STEP

DESCRIPTION

LOCAL

8

ENSURE that the Produced Water Transfer Pump selected for service has shut down on demand from the LP Separator oil/water interface controller. SET the pumps to manual and STOP from the CCR for both produced water transfer pumps. This is to prevent the pumps AUTO-STARTING on demand when the LP Separator is water flushed later in the procedure.

*

9

At this point in the procedure it will be necessary to WATER FLUSH the separation vessels in preparation for boundary isolation using the sand jetting facilities and utility seawater. The Marine Supervisor must SELECT the appropriate tank loading sequence to LINE UP the Oil Processing Facilities to the Crude Oil Storage Tanks.

10

CONNECT a hose suitable for jetwashing operations to the hose connection for the HP separator jetting water manifold and INTRODUCE seawater into the vessel by OPENING the individual Jetting Water Valve(s).

11

Slowly RAISE the setpoint of Oil/Water Interface Level Controller 10LIC-0111 for the HP separator to increase the produced water level in the separator to just above the weir (@ +1.11m above the vessel bottom elevation).

*

PCS

*

*

Note: This action will eventually introduce seawater into the oilside of the HP Separator, which in time will displace all the oil from the vessel through the HP Crude Oil Heater to the MP Separator. Once flushing operations on the HP separator have been completed, the Test separator can be FLUSHED to the MP Separator in an identical manner. 12

JETWASH the HP Separator until all crude has been displaced from the vessel. The belly drains for the vessel can be periodically opened to the Skid Drip Pan to confirm when all oil is displaced from the vessel.

*

*

Note: To ensure that there is adequate pressure differential (about 2bar) to drive the crude to downstream oil processing system, it may be necessary to recharge the HP Separator pressure with nitrogen and/or lowering the pressure of the MP separator.


Page 73 / 81



DESCRIPTION

LOCAL

PCS

13

SLOWLY LOWER the produced water level in the HP Separator to a minimum without gas blowby by DECREASING the setpoint of 10LIC-0111 to just below the trip setting (@ +0.2m above the vessel bottom elevation). MONITOR the decreasing level in the HP separator via the Local Gauge 10-LG-0116.

*

*

14

SLOWLY LOWER the oil level in the HP separator to a minimum without gas blowby by DECREASING the setpoint of Level Controller 10-LIC-0114 to just below the trip setting (@ +0.95m above vessel bottom elevation). MONITOR the decreasing level in the separator via Local Gauge 10-LG-0117.

*

*

*

*

Note: The field operator must ENSURE that the PSD Isolation Valve 10-XV-0118 on the oil outlet from the vessel and also 40-XV0103 and 40-XV-0104 at the HP Hydrocyclone move to the CLOSED position as a result of procedural steps 15 and 16 above. This is to test the effectiveness of the shutdown system. 15

The Test Separator can be isolated in a similar manner to the HP Separator.

16

CONNECT a hose suitable for jet-washing operations to the hose connection for the MP Separator jetting water manifold and INTRODUCE seawater into the vessel by OPENING the individual Jetting Water Valve(s).

17

Slowly RAISE the setpoint of Oil/Water Interface Level Controller 10LIC-0211 for the MP Separator to increase the produced water level in the separator to just above the weir (@ +1.28m above vessel bottom elevation).

*

Note: This action will eventually introduce seawater into the oil side of the MP separator which in time will displace all the oil from the vessel through the MP crude oil heater to the LP separator. 18

JETWASH the MP Separator until all crude has been displaced from the vessel. The belly drains for the vessel can be periodically opened to the Skid Drip Pan to confirm when all oil is displaced from the vessel.


*

*

Page 74 / 81



DESCRIPTION

LOCAL

PCS

19

SLOWLY LOWER the produced water level in the MP Separator to a minimum without gas blowby by DECREASING the setpoint of 10LIC-0211 to just below the trip setting (@ +0.2m above the vessel bottom elevation). MONITOR the decreasing level in the MP separator via the Local Gauge 10-LG-0216.

*

*

20

SLOWLY LOWER the oil level in the MP separator to a minimum without gas blowby by DECREASING the setpoint of Level Controller 10-LIC-0214 to just below the trip setting (@ +1.14m above the vessel bottom elevation). MONITOR the decreasing level in the separator via the Local Gauge 10-LG-0217.

*

*

*

*

Note: The field operator must ENSURE that the PSD Isolation Valve 10-XV-0218 on the oil outlet from the vessel and also 40-XV0203 and 40-XV-0204 at the MP Hydrocyclone move to the CLOSED position as a result of actions 21 and 22 above. This is to test the effectiveness of the shutdown system. 21

CONNECT a hose suitable for jet-washing operations to the hose connection for the LP Separator jetting water manifold, and INTRODUCE seawater into the vessel by OPENING the individual Jetting Water Valve(s).

22

Slowly RAISE the setpoint of Oil/Water Interface Level Controller 10LIC-0311 for the LP Separator to increase the produced water level in the separator to just above the weir (@ +1.28m above the vessel bottom elevation).

*

Note: This action will eventually introduce seawater into the oil side of the LP separator which in time will displace all the oil from the vessel. 23

As the crude inventory in the LP separator is replaced by seawater ENSURE that the duty crude oil transfer continues to operate normally. The crude oil transfer pumps are designed to pump crude oil from the separator to the electrostatic coalescer with a maximum water content of 0.05% (volume), so it is bad operating practice to pump water for a prolonged period of time.

*

24

JETWASH the LP Separator until all crude has been displaced from the vessel. The belly drains for the vessel can be periodically opened to the Skid Drip Pan to confirm when all oil is displaced from the vessel.

*


*

Page 75 / 81



DESCRIPTION

LOCAL

PCS

25

SLOWLY LOWER the water level in the LP separator to just below the trip setting (@ +0.2m above the vessel bottom elevation) by opening the belly drains for the vessel. MONITOR the decreasing level in the LP separator via the Local Gauge 20-LG-0317.

*

*

Note: The Field Operator must ENSURE that the PSD Isolation Valve 10-XV-0334 on the produced water outlet from the vessel moves to the CLOSED position as a result of this action. This is to test the effectiveness of the shutdown system. 26

INSTALL the override for the Low low Oil Level Trip 10-LSLL-0406 for the Electrostatic Coalescer. As the flowrate of crude oil to this vessel from the duty crude oil transfer pump DECREASES the operating level in the coalescer will fall.

*/CCR

27

RAISE the setpoint of oil/water Interface Level Controller 10-LIC-0401 to 100%. This will ensure that all crude is removed from the vessel.

*/CCR

28

SWITCH OFF the power to the electrodes for the Electrostatic Coalescer at the Local Control Panel prior to commencement of drain down operations from the coalescer.

*

29

SLOWLY LOWER the oil level in the LP separator to a minimum without gas blowby by DECREASING the setpoint of Level Controller 10-LIC-0314 to just below the trip setting (@+1.15m above the vessel bottom elevation). MONITOR the decreasing level in the separator via the Local Gauge 10-LG-0317.

*

*

Note: The Field Operator must ENSURE that the PSD Isolation Valve 10-XV-0335 on the oil outlet from the vessel moves to the CLOSED position and the duty crude oil transfer pump trips as a result of this action. This will stop all forward flow of seawater and any remaining crude and test the effectiveness of the shutdown system. 30

DEPRESSURISE the Test separator to the HP Flare System by OPENING the Pressure Controller 10-PIC-0507 for the vessel in MANUAL mode. This will TRIP the Test separator on low low pressure.

*

Note: The Field Operator must ENSURE that the PSD Isolation Valve 21-XV-1191 on the gas outlet line from the Test separator moves to the CLOSED position. This is to test the effectiveness of the shutdown system.


Page 76 / 81



DESCRIPTION

LOCAL

31

DEPRESSURISE the HP separator to the HP Flare System by OPENING the Pressure Controller 10-PIC-0107 for the vessel in MANUAL mode. This will TRIP the HP separator on low low pressure.

*

PCS

Note: The Field Operator must ENSURE that the PSD Isolation Valve 22-XV-1051 and Bypass Valve 22-XV-1052 on the gas outlet line from the HP separator moves to the CLOSED position. This is to test the effectiveness of the shutdown system. 32

DEPRESSURISE the MP separator to the HP Flare System by FULLY OPENING the Pressure Controller 10-PIC-0207 for the vessel in MANUAL mode. This will TRIP the MP separator on low low pressure.

*

Note: The Field Operator must ENSURE that the PSD Isolation Valve 22-XV-1201 and Bypass Valve 22-XV-1202 on the gas outlet line from the MP separator move to the CLOSED position as a result of this action. This is to test the effectiveness of the shutdown system. 33

DEPRESSURISE the LP separator to the LP Flare System by FULLY OPENING the Pressure Controller 10-PIC-0307 for the vessel in MANUAL mode This will TRIP the LP separator on low low pressure.

*

Note: The Field Operator must ENSURE that the PSD Isolation Valve 22-XV-1221 on the gas outlet line from the LP separator moves to the CLOSED position as a result of this action. This is to test the effectiveness of the shutdown system. 34

CLOSE the 4in isolation ball valve on the heating medium supply line to the HP crude oil heater and ENSURE the PSD Isolation Valve 44XV-2017 on the heating medium return line from the heater is CLOSED.

*

35

CLOSE the 6in isolation ball valves on the heating medium supply and return lines for the MP Crude Oil heater.

*

36

CLOSE the 6in isolation ball valves on the cooling medium supply and return lines to and from the crude oil cooler.

*


Page 77 / 81


Operating Procedures 5.05 Unplanned Shutdown of the Oil Processing Facilities 5.05.1 Preamble

The following unplanned shutdown procedure describes the shutdown of the oil processing facilities as part of a Process Trip or Production Stop.

The unplanned shutdown procedure for the Oil Processing Facilities can be summarised in the following major steps: • •

Methanol injection into the wellhead Depressurise all flowlines to the separation vessels in the oil processing facilities


Page 78 / 81


Operating Procedures 5.05.2 Unplanned Shutdown Procedure STEP

DESCRIPTION

LOCAL

PCS

*

*

There are several unplanned shutdown scenarios with each case requiring different actions. 

Short shutdowns where an immediate restart is expected and the temperature downstream of the subsea chokes does not drop below 22 °C will not require shutdown actions.



Short shutdown where restart is expected to be within the flowline no touch time (likely no less than 4 hours). Inject methanol upstream and downstream of all producing wells subsea chokes.



Shutdowns expected to exceed 4 hours where the flowline temperature falls below the hydrate formation temperature of 20°C. Inject methanol upstream and downstream of all producing wells subsea chokes and depressurise the flowlines if possible.

Note: if wells remain open under a process trip then a restart is required or all tree valves should be closed before the pipeline pressure rises above circa. 50barg. Methanol Injection 1

Inject 0.5m³ of methanol upstream and downstream of the subsea choke for each producing well in turn to protect the immediate area that is subject to rapid cooldown. Flowline Depressurisation

2

All flowlines must be DEPRESSURISED to 10barg for flowline hydrate suppression if the shutdown time is to exceed 4 hours. It will be necessary to temporarily install the overrides for the Low Low Pressure Trips 07PALL-301, 07-PALL-201 and 07-PALL-101 on the risers prior to the start of depressurisation. Depressurisation should be carefully controlled and the rate should not exceed 100 bar/hour for the Curlew D Risers and 10 bar/hour for Riser B1.

*

3

SLOWLY REDUCE the setpoint of the Pressure Controller for the HP separator and Test separator from operating pressure to about 10barg. This allows the Curlew flowlines to settle out to separator pressure.

*

4

CLOSE the Tree Valves AMV, PUMV and PWV in addition to the subsea choke valves for all Curlew wells.

*

5

Once the Curlew flowlines are depressurised to 10barg CLOSE the Topsides Choke Valves (07-PCV-0109, 07-PCV-0209 and 07-PCV-0309).

*


Page 79 / 81



5.06 Process and Emergency Cause and Effect Charts

5.07 Pressure Safety Valve Five Key Interlock Operations

Refer to Drawing Nos CUR-MAS-PB-20655.

Figure 5.01 on the following page shows a typical PSV arrangement with PSV ‘A’ in service and PSV ‘B’ isolated in the maintenance position. The purpose of the 5 key Interlock System is to ensure that one PSV is always on line. Each isolating valve has two (2) locks. One lock has a key locked in, the second has the key removed. The fifth key is held by the Production Supervisor. The valves are changed out as follows: •

Obtain the ‘A’ key for the PSV set from the Production Supervisor

•

Insert the ‘A’ key in the empty lock on the closed flare side valve on PSV ‘B’ and open the valve to release the trapped ‘B’ key. The supervisors ‘A’ key remains in the lock

•

Insert the retrieved ‘B’ key in the locked closed valve below PSV ‘B’ and open the valve to release the trapped ‘C’ key. The ‘B’ key originally from the flare side of PSV ‘B’ remained trapped

•

Insert the retrieved ‘C’ key in the locked open valve below PSV ‘A’ and close the valve to release the trapped ‘D’ key. The ‘C’ key originally from the process side valve of PSV ‘B’ remains trapped

•

Insert the ‘D’ key in the locked open flare side valve on PSV ‘A’ and close the valve to release the trapped ‘E’ key. The final ‘E’ key is now released and returned to the supervisor

This sequence is for switching B into service and isolating A. The procedures is reversed to switch from A to B. For a full maintenance isolation of both PSVs, typically when the process vessel is to be removed from service for a vessel entry, then a sixth key (the maintenance key) is required to enable all four isolation valves to be closed.


Page 80 / 81



INTERLOCKED VALVES TO FLARE HEADER

PSV B

PSV A

FLARE SIDE VALVE

FLARE SIDE VALVE

VESSEL SIDE VALVE

VESSEL SIDE VALVE

VESSEL

NOTE: Relief valve PSV shown isolated for maintenance. In normal operation both flare side isolation valves are open. The on-line relief valve vessel side isolation valve in open and the off-line valve vessel side isolation valve in closed.

N41B3.005

Fig 5.01 Interlocked Pressure Safety Valves


Page 81 / 81

Isolation/Reinstatement Procedures


Isolation/Reinstatement Procedures 6.01

6.01.5 6.01.6

Oil Processing Facilities, Boundary Isolation, Flushing, Draining and Nitrogen Purging Operations Introduction Preconditions Boundary Isolation Oil Processing Facilities, Flushing Operation - Part 1 Oil Processing Facilities, Flushing Operation - Part 2 Oil Processing Facilities, Nitrogen Purging Operation Oil Processing Facilities Boundary Isolation Valve Checklist

6.02 6.02.1 6.02.2 6.02.3 6.02.4

Test Separator V-1005 Preconditions Preparation for Vessel Entry Procedure Reinstatement Procedure Spading Checklist V-1005

6.03 6.03.1 6.03.2 6.03.3 6.03.4

HP Separator V-1001 Preconditions Preparation for Vessel Entry Procedure Reinstatement Procedure Spading Checklist V-1001

6.04 6.04.1 6.04.2 6.04.3 6.04.4

HP Crude Oil Heater E-1001 Preconditions Isolation Procedure Reinstatement Procedure Spading Checklist E-1001

6.05 6.05.1 6.05.2 6.05.3 6.05.4

MP Separator V-1002 Preconditions Preparation for Vessel Entry Procedure Reinstatement Procedure Spading Checklist V-1002

6.06 6.06.1 6.06.2 6.06.3 6.06.4

MP Crude Oil Heater E-1002 Preconditions Isolation Procedure Reinstatement Procedure Spading Checklist E-1002

6.07 6.07.1 6.07.2 6.07.3 6.07.4

LP Separator V-1003 Preconditions Preparation for Vessel Entry Procedure Reinstatement Procedure Spading Checklist V-1003

6.01.1 6.01.2 6.01.3 6.01.4


Page 1 / 105



Isolation/Reinstatement Procedures (Continued)

6.08 6.08.1 6.08.2 6.08.3 6.08.4 6.08.5 6.08.6 6.08.7

Produced Water Transfer Pumps P-1002A/B Preconditions Isolation Procedure Reinstatement Procedure Valve Isolation Checklist P-1002A (Stand-alone) Valve Isolation Checklist P-1002B (Stand-alone) Spading Checklist P-1002A Spading Checklist P-1002B

6.09 6.09.1 6.09.2 6.09.3 6.09.4 6.09.5 6.09.6 6.09.7

Crude Oil Transfer Pumps P-1001A/B Preconditions Isolation Procedure Reinstatement Procedure Valve Isolation Checklist P-1001A (Stand-alone) Valve Isolation Checklist P-1001B (Stand-alone) Spading Checklist P-1001A Spading Checklist P-1001B

6.10 6.10.1 6.10.2 6.10.3 6.10.4

Electrostatic Coalescer V-1004 Preconditions Preparation for Vessel Entry Procedure Reinstatement Procedure Spading Checklist V-1004

6.11 6.11.1 6.11.2 6.11.3 6.11.4

Export Crude Oil Cooler E-1004 Preconditions Isolation Procedure Reinstatement Procedure Spading Checklist E-1004

6.12 Oil Processing Facilities Boundary Reinstatement 6.12.1 Introduction 6.12.2 Boundary Reinstatement


Page 2 / 105


6.01 Oil Processing Facilities, Boundary Isolation, Flushing, Draining and Nitrogen Purging Operations 6.01.1 Introduction


WARNING: THIS PROCEDURE MUST BE READ AND FULLY UNDERSTOOD BEFORE ATTEMPTING TO CARRY OUT ANY ACTION.

The oil processing facilities have been shut down, and jetwashed with utility seawater in preparation for major maintenance activities. Details of this operation are described in the planned shutdown procedure included in Section 5.05 of this book. The Boundary Isolation provides a safe haven for work to be conducted within the whole system, specifically during an annual shutdown for maintenance activities. Each Work Permit issued thereafter shall have a copy of the Boundary Isolation issued with it, together with any Mechanical (spading), Electrical or Instrument isolations and any Vessel Entry Permits required for the specific task in hand. The Boundary Isolation shall remain in place until all work within its confines has been completed.


Page 3 / 105




(1)

All the necessary Work Permits have been raised and authorised prior to commencing this procedure and controls have been established in accordance with Maersk Work Permit Procedures.

(2)

No operations or Work Permits are in force which may prohibit this procedure.

(3)

The following equipment is electrically isolated and an Electrical Isolation Certificate issued for each facility: Heat Tracing Circuits for all Pipework and Instrumentation Produced Water Transfer Pumps, P-1002A/B Crude Oil Transfer Pumps, P-1001A/B Electrostatic Coalescer, V-1004 All Chemical Injection Pumps for the Oil Processing Facilities

(4)

The Subsea Control System for the oil production wells is no longer required for service. Therefore the Topsides HPU, EPU and MCS have been shut down for an extended period. Details on the shutdown of the subsea control system are provided in Section 5 of Operating Procedures Manual Volume 1 Book A - Subsea Facilities.

6.01.2 (5) Preconditions (Continued)

There is sufficient capacity in the Hazardous Drains Collection Tank T-6001 to accept the flushed contents of vessels, pumps and equipment in the Oil Processing Facilities. Excess liquids from the hazardous drains collection tank are routinely pumped to the Port Slops Tank for safe disposal.

(6)

All pipework rendered open-ended during the isolation of plant for the maintenance/inspection must be spaded/blanked off to the potentially live section of line with correctly rated flanges.

This procedure should be used in conjunction with the Boundary Isolation Checklist, and with the following marked up P&IDs included at the end of the procedure. WARNING: THE EXEMPLARY PROCEDURES INCLUDED IN THIS SECTION WERE RAISED IN 1996 AND ARE INCLUDED NOW AS AN AID TO OPERATORS. ACTUAL ISOLATIONS MUST BE MADE AGAINST LATEST CONTROLLED COPIES OF THE P&IDS AND IN ACCORDANCE WITH THE CURRENT OPERATIONAL MANAGEMENT SYSTEM, SPECIFICALLY THE ISOLATIONS STANDARDS AND PROCEDURES.


Page 4 / 105



6.01.3 Boundary Isolation

The closing and securing of all isolation valves and isolation of electrical equipment must be in accordance with Maersk Isolation Philosophy Document Number CUR-MAS-PB-20656.

Refer to P&ID CUR-MAS-TP-42035-001

(1)

ENSURE that the Spare Riser ESD Valve 07-XXV-0500 is CLOSED, then DISABLE and TAG the hydraulically operated actuator.

(2)

ENSURE that the Double Block and Bleed Valve for the Spare Riser low point drain line (downstream of the ESD valve) is CLOSED, then LOCK and TAG the valve.

(3)

ENSURE that the Double Block and Bleed Valve for the Spare Flowline methanol injection point is CLOSED, then LOCK and TAG the valve.

(4)

ENSURE that the Spare Flowline ESD Valve 07-XV-0505 is CLOSED, then DISABLE and TAG the hydraulically operated actuator.

(5)

ENSURE that the Double Block and Bleed Valve for the Spare Flowline corrosion inhibitor injection point is CLOSED, then LOCK and TAG the valve.

(6)

ENSURE that the Double Block and Bleed Valve for the Spare Flowline low point drain line (downstream of the topsides choke valve) is CLOSED.

(7)

ENSURE that the BP1 Riser ESD Valve 07-XXV-300 is CLOSED, then DISABLE and TAG the hydraulically operated actuator.

(8)

ENSURE that the Double Block and Bleed Valve for BP1 Riser low point drain line (downstream of the ESD valve) is CLOSED, then LOCK and TAG the valve.

(9)

ENSURE that the Double Block and Bleed Valve for BP1 Flowline methanol injection point is CLOSED, then LOCK and TAG the valve.

(10)

ENSURE that the BP1 Flowline ESD Valve 07-XV-305 is CLOSED, then DISABLE and TAG the hydraulically operated actuator.

(11)

ENSURE that the Double Block and Bleed Valve for BP1 Flowline corrosion inhibitor injection point is CLOSED, then LOCK and TAG the valve.

(12)

ENSURE that the Double Block and Bleed Valve for BP1 Flowline low point drain line (downstream of the topsides choke valve) is CLOSED.

Refer to P&ID CUR-MAS-TP-42002-001

Note: DO NOT LOCK this valve closed until after the flushing operation. ID: M-CPH-1171-01417_EN_Section_6.doc

Page 5 / 105



6.01.3 Boundary Isolation (Continued)

(13)

ENSURE that the DP1 Riser ESD Valve 07-XXV-200 is CLOSED, then DISABLE and TAG the hydraulically operated actuator.

(14)

ENSURE that the Double Block and Bleed Valve for DP1 Riser low point drain line (downstream of the ESD valve) is CLOSED, then LOCK and TAG the valve.

(15)

ENSURE that the Double Block and Bleed Valve for DP1 Flowline methanol injection point is CLOSED, then LOCK and TAG the valve.

(16)

ENSURE that the DP1 Flowline ESD Valve 07-XV-205 is CLOSED, then DISABLE and TAG the hydraulically operated actuator.

(17)

ENSURE that the Double Block and Bleed Valve for DP1 Flowline corrosion inhibitor injection point is CLOSED, then LOCK and TAG the valve.

(18)

ENSURE that the Double Block and Bleed Valve for DP1 Flowline low point drain line (downstream of the topsides choke valve) is CLOSED.

Note: DO NOT LOCK this valve closed until after the flushing operation. (19)

ENSURE that the DP2 Riser ESD Valve 07-XXV-100 is CLOSED, then DISABLE and TAG the hydraulically operated actuator.

(20) ENSURE that the Double Block and Bleed Valve for DP2 Riser low point drain line (downstream of the ESD valve) is CLOSED, then LOCK and TAG the valve. (21)

ENSURE that the Double Block and Bleed Valve for DP2 Flowline methanol injection point is CLOSED, then LOCK and TAG the valve.

(22) ENSURE that the DP2 Flowline ESD Valve 07-XV-105 is CLOSED, then DISABLE and TAG the hydraulically operated actuator. (23) ENSURE that the Double Block and Bleed Valve for DP2 Flowline corrosion inhibitor injection point is CLOSED, then LOCK and TAG the valve. (24) ENSURE that the Double Block and Bleed Valve for DP2 Flowline low point drain line (downstream of the topsides choke valve) is CLOSED.

Note: DO NOT LOCK this valve closed until after the flushing operation. ID: M-CPH-1171-01417_EN_Section_6.doc

Page 6 / 105


Refer to P&ID CUR-MAS-PM-20048-501


(25)

CLOSE, LOCK and TAG the ½in Isolation Block Valve HV-73007 at the demulsifier injection point on the inlet header to the Test separator.

(26)

CLOSE, LOCK and TAG the ½in Isolation Block Valve HV-73009 at the defoamer injection point on the inlet header to the Test separator.

(27)

ENSURE that the ESD Valve 10-XV-0501 on the Blowdown Line from the Test separator to the HP Flare Header is CLOSED, then CLOSE, LOCK and TAG the downstream isolation ball valve.

(28)

ENSURE that the three 1in Isolation Ball Valves on the manual depressurisation line to LP Flare for the Test separator are CLOSED.

Note: DO NOT LOCK these valves closed until after the nitrogen purge operation. (29)

CLOSE, LOCK and TAG the 6in isolation ball valves downstream of Pressure Safety Relief Valves 10-PSV-0503A and 10-PSV-0503B.

Note: This will require the use of the sixth key (maintenance key) and will result in all four isolation valves for the interlocked pressure safety relief valves being closed. (30)

ENSURE that the isolation valves to HP Flare for the bypass line around the pressure safety relief valves are CLOSED, then LOCK and TAG the valves.

(31)

ENSURE that the isolation valves for the gas outlet sample line are CLOSED, then LOCK and TAG the valves.

(32)

CLOSE, LOCK and TAG the Double Block and Bleed Valve HV-10253/4 downstream of 10-PCV-0507B on the gas outlet line from the Test separator to the HP Flare Header.

(33)

CLOSE, LOCK and TAG the Double Block and Bleed Valve HV-10258/9 downstream of 10-PCV-0507A on the gas outlet line from the Test separator to the Gas Compression Facilities.

(34)

ENSURE that the isolation valves HV-10283 and HV-10284 for the crude outlet sample line are CLOSED.

Note: DO NOT LOCK these valves closed until after the flushing operation. ID: M-CPH-1171-01417_EN_Section_6.doc Page 7 / 105



(35)

CLOSE, LOCK and TAG the 4in Isolation Ball Valve HV-10281 on the produced water outlet line from the Test separator to the Test Hydrocyclone/HP Hydrocyclone.

(36)

ENSURE that the Jetting Water Valve HV-10273 is CLOSED.

(37)


(38)


Note: DO NOT LOCK these valves closed until after the flushing operation.

Refer to P&ID CUR-MAS-PB-20048-002

6.01.3 Boundary Isolation (Continued) Refer to P&ID CUR-MAS-PM-20041-501

(39)

ENSURE that the PSD Valve 20-XV-1191 for the gas outlet from the Test separator is CLOSED, then DISABLE and TAG the pneumatically operated actuator.

(40)

CLOSE, LOCK and TAG the ½in Isolation Block Valve HV-73001 at the demulsifier injection point on the inlet header to the HP Separator

(41)

CLOSE, LOCK and TAG the ½in Isolation Block Valve HV-73002 at the defoamer injection point on the inlet header to the HP Separator.

(42)

ENSURE that the ESD Valve 10-XV-0101 on the Blowdown Line from the HP separator to the HP Flare Header is CLOSED, then CLOSE, LOCK and TAG the downstream isolation ball valve.

(43)

ENSURE the 1in Isolation Ball Valves on the manual depressurisation line for the HP separator are CLOSED.

Note: DO NOT LOCK these valves closed until after the nitrogen purge operation. (44)

CLOSE, LOCK and TAG the 8in isolation ball valves downstream of Pressure Safety Relief Valves 10-PSV-0103A and 10-PSV0103B.

Note: This will require the use of the sixth key (maintenance key) and will result in all four isolation valves for the interlocked pressure ID: M-CPH-1171-01417_EN_Section_6.doc

Page 8 / 105



safety relief valves being closed. (45)

ENSURE that the isolation valves for the bypass line around the pressure safety relief valves are CLOSED, then LOCK and TAG the valves.

(46)

ENSURE that the isolation valve HV-10021 for the gas outlet sample line are CLOSED, then LOCK and TAG the valves.

(47)

ENSURE that the isolation valves HV-10049 and HV-10050 for the crude outlet sample line are CLOSED.

Note: DO NOT LOCK these valves closed until after the flushing operation. (48)

CLOSE, LOCK and TAG the 6in Isolation Ball Valve HV-10046 on the produced water outlet line from the HP separator to the HP Hydrocyclone/Test Hydrocyclone.

(49)


(50)



Page 9 / 105


Isolation/Reinstatement Procedures 6.01.3 Boundary Isolation (Continued)

(51)


(52)


(53)


Note: DO NOT LOCK these valves closed until after the flushing operation. Refer to P&ID CUR-MAS-PB-20041-002



(54)

CLOSE, LOCK and TAG the 14in Isolation Ball Valve HV-22001 downstream of 10-PCV-0107 on the gas outlet line from the HP separator to the HP Flare Header.

(55)

CLOSE, LOCK and TAG the 4in Isolation Ball Valve HV-52002 on the gas outlet line from the HP separator to the Fuel Gas Cooler E5202.

(56)

ENSURE that the PSD Valve 22-XV-1051 for the gas outlet from the HP separator is CLOSED, then DISABLE and TAG the pneumatically operated actuator.

(57)

ENSURE that the Bypass Valve 22-XV-1052 for the gas outlet from the HP separator is CLOSED, then DISABLE and TAG the pneumatically operated actuator.

(58)

CLOSE, LOCK and TAG the 10in Isolation Ball Valve HV-22002 on the gas outlet line from the HP separator to the Inlet Cooler E-2201.

(59)

ENSURE that the PSD Isolation Valve 44-XV-2017 on the heating medium return from the HP crude oil heater is CLOSED, then DISABLE and TAG the pneumatically operated actuator.

(60)

ENSURE that the 4in Isolation Ball Valve HV-44054 on the heating medium supply to the HP crude oil heater is CLOSED, then LOCK and TAG the valve.

(61)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-10067 downstream of 10-PSV-0153 for the crude oil outlet from the HP crude oil heater.

(62)

CLOSE, LOCK and TAG the ½in Isolation Block Valve HV-73004 at the demulsifier injection point on the inlet header to the MP Separator

(63)

CLOSE, LOCK and TAG the ½in Isolation Block Valve HV-73006 at the defoamer injection point on the inlet header to the MP Separator


Page 10 / 105


Isolation/Reinstatement Procedures 6.01.3 Boundary Isolation (Continued)

(64)

ENSURE that the ESD Valve 10-XV-0201 on the Blowdown Line from the MP separator to the LP Flare Header is CLOSED, then CLOSE, LOCK and TAG the downstream 12in isolation ball valve HV-10079.

(65)

CLOSE, LOCK and TAG the 8in isolation ball valves downstream of Pressure Safety Relief Valves 10-PSV-0203A and 10-PSV0203B.

Note: This will require the use of the sixth key (maintenance key) and will result in all four isolation valves for the interlocked pressure safety relief valves being closed. (66)

ENSURE that the isolation valves for the 1in bypass line around the pressure safety relief valves are CLOSED.

Note: DO NOT LOCK these valves closed until after the purging operation. (67)

ENSURE that the isolation valves HV-10091/2 for the gas outlet sample line are CLOSED, then LOCK and TAG the valves.

(68)

CLOSE, LOCK and TAG the Isolation Ball Valve HV-10090 downstream of 10-PCV-0207B on the gas outlet line from the MP separator to the HP Flare Header.

(69)

ENSURE that the isolation valves HV-10116/7 for the crude outlet sample line are CLOSED.

Note: DO NOT LOCK these valves closed until after the flushing operation. (70)

CLOSE, LOCK and TAG the 6in Isolation Ball Valve HV-10112 on the produced water outlet line from the MP separator to the MP Hydrocyclone.

(71)


(72)


(73)


(74)


(75)


Note: DO NOT LOCK these valves closed until after the flushing operation.


Page 11 / 105



6.01.3 Boundary Isolation (Continued) Refer to P&ID CUR-MAS-PB-20043-002







(76)

ENSURE that the PSD Valve 20-XV-1201 for the gas outlet from the MP separator is CLOSED, then DISABLE and TAG the pneumatically operated actuator.

(77)

ENSURE that the Bypass Valve 20-XV-1202 for the gas outlet from the MP separator is CLOSED, then DISABLE and TAG the pneumatically operated actuator.

(78)

CLOSE, LOCK and TAG the 4in Isolation Ball Valve HV-22039 downstream of 22-LCV-0009 to the MP Separator.

(79)

CLOSE, LOCK and TAG 22-LCV-0009 3in bypass valve HV-22038.

(80)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-10007 downstream of 20-LCV-1135 to the MP Separator.

(81)

CLOSE, LOCK and TAG 20-LCV-1135 1in bypass valve HV-10008

. (82)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-40037 on the reject oil line from the Test separator hydrocyclone downstream of 40-PCV-0301.

(83)

CLOSE, LOCK and TAG the 1in Isolation globe Valve HV-40040 on the bypass line for 40-PCV-0301.

(84)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-40021 on the reject oil line from the MP separator hydrocyclone downstream of 40-PCV-0201.

(85)


(86)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-40003 on the reject oil line from the HP separator hydrocyclone downstream of 40-PCV-0101.

(87)


(88)

ENSURE that the PSD Valve 10-XV-1081 for the dump line from the fuel gas scrubber is CLOSED, then DISABLE and TAG the pneumatically operated actuator.


Page 12 / 105


Isolation/Reinstatement Procedures 6.01.3 Boundary Isolation (Continued) Refer to P&ID CUR-MAS-PB-20112-001




(89)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-20012 for the LP Suction Scrubber Pump P-2002A discharge line to the MP crude oil heater.

(90)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-20015 for the LP Suction Scrubber Pump P-2002B discharge line to the MP crude oil heater.

(91)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-10008 for the HP Flare KO Drum Pump P-5001A discharge line to the MP crude oil heater.

(92)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-10009 for the HP Flare KO Drum Pump P-5001B discharge line to the MP crude oil heater.

(93)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-10010 for the LP Flare KO Drum Pump P-5101A discharge line to the MP crude oil heater.

(94)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve HV-10011 for the LP Flare KO Drum Pump P-5101B discharge line to the MP crude oil heater.

(95)

CLOSE, LOCK and TAG the Isolation Ball Valve HV-20031 downstream of 20-LCV-1098 on the liquid outlet line from the MP suction scrubber to the MP crude oil Heater.

(96)


CLOSE, LOCK and TAG the isolation globe valve HV-20074 on 20-LCV-1098 bypass line. (97) ENSURE that the 6in Isolation Ball Valve HV-44072 on the heating medium return from the MP crude oil heater is CLOSED, then LOCK and TAG the valve. (98)

ENSURE that the 6in Isolation Ball Valve HV-44064 on the heating medium supply to the MP crude oil heater is CLOSED, then LOCK and TAG the valve.

(99)

CLOSE, LOCK and TAG the Isolation Ball Valve HV-10126 downstream of 10-PSV-0253 on the crude oil inlet to the MP crude oil heater.


Page 13 / 105




(100) ENSURE that the ESD Valve 10-XV-0301 on the Blowdown Line from the LP separator to the LP Flare Header is CLOSED, then CLOSE, LOCK and TAG the downstream 10in isolation ball valve HV-10135. (101) CLOSE, LOCK and TAG the 6in isolation ball valves downstream of Pressure Safety Relief Valves 10-PSV-0303A and 10-PSV0303B. Note: This will require the use of the sixth key (maintenance key) and will result in all four isolation valves for the interlocked pressure safety relief valves being closed. (102) ENSURE that the isolation valves for the 1in bypass line around the pressure safety relief valves are CLOSED. Note: DO NOT LOCK these valves closed until after the purging operation. (103) ENSURE that the isolation valves for the gas outlet sample line are CLOSED, then LOCK and TAG the valves. (104) CLOSE, LOCK and TAG the Isolation Ball Valve HV-10136 downstream of 10-PCV-0307B on the gas outlet line from the LP separator to the LP Flare Header. (105) ENSURE that the isolation valves HV-10160/1 for the crude outlet sample line are CLOSED. Note: DO NOT LOCK these valves closed until after the flushing operation. (106) ENSURE that the Jetting Water Valve HV-10140 is CLOSED. (107) ENSURE that the Jetting Water Valve HV-10142 is CLOSED. (108) ENSURE that the Jetting Water Valve HV-10144 is CLOSED. (109) ENSURE that the Jetting Water Valve HV-10146 is CLOSED. (110) ENSURE that the Jetting Water Valve HV-10148 is CLOSED. Note: DO NOT LOCK these valves closed until after the flushing operation.


(111) ENSURE that the PSD Valve 20-XV-1221 for the gas outlet from the LP separator is CLOSED, then DISABLE and TAG the pneumatically operated actuator.


Page 14 / 105




(112) CLOSE, LOCK and TAG the isolation ball valves downstream of Pressure Safety Relief Valves 10-PSV-0403A/B. (113) ENSURE that the Drain Valve No 1 for the coalescer bushings at Nozzle N5A is CLOSED, then LOCK and TAG the valve. (114) ENSURE that the Drain Valve No 2 for the coalescer bushings at Nozzle N5A is CLOSED, then LOCK and TAG the valve. (115) ENSURE that the Drain Valve No 1 for the coalescer bushings at Nozzle N5B is CLOSED, then LOCK and TAG the valve. (116) ENSURE that the Drain Valve No 2 for the coalescer bushings at Nozzle N5B is CLOSED, then LOCK and TAG the valve. (117) ENSURE that the Isolation Valves for Sample Line No 1 at Nozzle N6A are CLOSED. (118) ENSURE that the Isolation Valves for Sample Line No 2 at Nozzle N6B are CLOSED. (119) ENSURE that the Isolation Valves for Sample Line No 3 at Nozzle N6C are CLOSED. (120) ENSURE that the Isolation Valves for Sample Line No 4 at Nozzle N6D are CLOSED. (121) ENSURE that the Isolation Valves for Sample Line No 5 at Nozzle N6E are CLOSED.


(122) ENSURE that the 6in Isolation Ball Valve HV-45101 on the cooling medium return from the export crude oil cooler is CLOSED, then LOCK and TAG the valve. (123) ENSURE that the 6in Isolation Ball Valve HV-45103 on the cooling medium supply to the export crude oil heater is CLOSED, then LOCK and TAG the valve. (124) ENSURE that the PSD Valve 10-XV-0458 for the crude outlet from the export crude oil cooler is CLOSED, then DISABLE and TAG the pneumatically operated actuator.


Page 15 / 105



6.01.4 Oil Processing Facilities, Flushing Operation Part 1

CAUTION: THE WATER FLUSHING OPERATION DESCRIBED IN STEPS 1 TO 23 DETAILS THE FLUSHING OF THE FLOWLINES, MANIFOLDS AND HEADERS TO THE TEST, HP AND MP SEPARATORS. THE FLUSHINGS FROM THE SEPARATORS ARE THEN DISPOSED OF TO THE HAZARDOUS AREA OPEN DRAINS. Note: The following procedure assumes ‘normal operation’ where Curlew fluids are produced to the HP Separator via the production swivel and to the Test separator via the test swivel. (1)

ENSURE that the low point drain lines for the Curlew Risers and flowlines are CONNECTED to the Port or Starboard hazardous drains collection tanks with correctly rated flexible hoses.

(2)

ENSURE that the Port or Starboard hazardous drains collection tanks have sufficient capacity to accept the crude drainings from the risers and flowlines by OBSERVING local gauge glasses fitted to the vessels. If this is not the case, the Port or Starboard hazardous drains tank pumps will AUTO-START on demand to control the rising level in the tanks. The discharges from the hazardous drains tank pumps are lined up to the Port Slops Tank, which is suitable for the storage of liquid hydrocarbons.

(3)

DRAIN the contents of the Risers and flowlines located below the turret to the Port or Starboard hazardous drains collection tanks by OPENING the double block and bleed valves for the low drain points. OPEN the valves for the Curlew flowlines to the test separation train and the production separation trains to facilitate full draindown. CLOSE the isolation valves for the low drain point on completion.

Note: Due to the mechanical interlocks fitted on the test and production diverter valves it is necessary to open these valves one at a time. (4)

CLOSE the test and production diverter valves for all flowlines then CONNECT a utility seawater supply hose to the flushing point for each flowline.

(5)

FLUSH all Curlew flowlines through the test manifold and test swivel to the Test separator.


Page 16 / 105



6.01.4 Oil Processing Facilities, Flushing Operation Part 1 (Continued)

(6)

ENSURE that there is no pressure remaining in the Test separator by REMOVING the blank then carefully OPENING the vent valves fitted to the level gauge glasses for the vessel. OPEN the four 2in Isolation valves for the belly drains to drain the contents of the Test separator to the hazardous area open drain via the Skid Drip Pan. The hazardous area open drain header directs all flushings to the Port Hazardous Drains Collection Tank T-6001 for subsequent disposal. CLOSE the belly drains on completion.

(7)

CONNECT a suitable seawater hose to the purge/utility connection of the Test separator. OPEN the isolation valve on the seawater supply and the purge/utility connection valve to flood the vessel. OPEN the four 2in Isolation valves for the belly drains to drain the contents of the separator to the hazardous area open drain header. This will remove all liquid hydrocarbons from the vessel.

(8)

REMOVE the blank then connect a suitable seawater hose to the vent valve for oil/water Interface Level Gauge 10-LG-0516. OPEN the isolation valve for the seawater supply and the drain valve to flush the level gauge to the hazardous area open drains.

(9)

FLUSH the following instrumentation for the Test separator to the hazardous area open drains: 

Interface Level Gauge 10-LG-0517

(10)

FLUSH the flowlines for the Curlew wells through the 8in Production Swivel X-0703 in the turret on to the HP separator.

(11)

ENSURE that there is no pressure remaining in the HP separator by REMOVING the blank then carefully OPENING the vent valves fitted to the level gauge glasses for the vessel. OPEN the six 2in Isolation valves for the belly drains to drain the contents of the HP separator to the hazardous area open drain via the Skid Drip Pan. The hazardous area open drain header directs all flushings to the Port Hazardous Drains Collection Tank T-6001 for subsequent disposal. CLOSE the belly drains on completion.

(12)

CONNECT a suitable seawater hose to the purge/utility connection of the HP separator. OPEN the isolation valve on the seawater supply and the purge/utility connection valve to flood the vessel. OPEN the six 2in Isolation valves for the belly drains to drain the contents of the separator to the hazardous area open drain header. This will remove all liquid hydrocarbons from the vessel.


Page 17 / 105




(13)


(14)

FLUSH the following instrumentation for the HP separator to the hazardous area open drains: 


(15)

CLOSE the Double Block and Bleed Valve downstream of 10-LCV-0114 on the crude oil outlet from the HP crude oil heater. Also ENSURE the 3in isolation ball valve HV-10073 for the bypass valve is CLOSED. CONNECT a utility seawater supply hose to the drain point on the upstream side of 10-LCV-0114.

(16)

OPEN the isolation valve for the seawater supply and the drain valve. Periodically OPEN the 1in isolation ball valve from the process inlet of the HP crude oil heater to the Skid Drip Pan to BACKFLUSH the heater to the hazardous open drains.

Note: If heating medium is available, it will be beneficial to recommission the HP crude oil heater in order to heat the utility seawater during flushing. (17)

SHUT OFF the seawater supply to the HP crude oil heater and DISCONNECT the supply hose. DRAIN the tubeside of the HP crude oil heater to the Skid Drip Pan. CLOSE the 1in isolation ball valve from the process inlet of the HP crude oil heater to the Skid Drip Pan on completion.

(18)

FLUSH the flowline for the Curlew BP1 well through the 8in Production Swivel X-0704 in the turret on to the MP separator.

(19)

ENSURE that there is no pressure remaining in the MP separator by REMOVING the blank then carefully OPENING the vent valves fitted to the level gauge glasses for the vessel. OPEN the six 2in Isolation valves for the belly drains to drain the contents of the MP separator to the hazardous area open drain via the Skid Drip Pan. The hazardous area open drain header directs all flushings to the Port Hazardous Drains Collection Tank T-6001 for subsequent disposal. CLOSE the belly drains on completion.


Page 18 / 105




(20)

CONNECT a suitable seawater hose to the purge/utility connection of the MP separator. OPEN the isolation valve on the seawater supply and the purge/utility connection valve to flood the vessel. OPEN the six 2in Isolation valves for the belly drains to drain the contents of the separator to the hazardous area open drain header. This will remove all liquid hydrocarbons from the vessel.

(21)


(22)

FLUSH the following instrumentation for the MP separator to the hazardous area open drains: 

(23)


Once the flowlines, manifolds and headers are completely flushed and the test, HP and MP Separators are drained of all liquids, ENSURE that the following drain valves are CLOSED, LOCKED and TAGGED: 

Double Block and Bleed Valves at the low drainage points for the Risers and flowlines



Double Block and Bleed Valve at the flush points for the flowlines

Note: The valves listed above are part of the Oil Processing Facilities Boundary Isolation Valve Checklist 6.01.6.


Page 19 / 105



6.01.4 Oil Processing Facilities, Flushing Operation Part 2

CAUTION: THE WATER FLUSHING OPERATION DESCRIBED IN STEPS 24 TO 42 DETAILS THE FLUSHING OF THE REMAINING EQUIPMENT IN THE OIL STABILISATION FACILITIES.

(24)

CLOSE the Isolation Ball Valve HV-10118 upstream of 10-LCV-0214 on the crude oil outlet from the MP separator. Also ENSURE that the 4in isolation ball valve HV-10080 for the bypass line is CLOSED. CONNECT a utility seawater supply hose to the drain point HV-10121 on the downstream side of 10-LCV-0214.

(25)

OPEN the isolation valve for the seawater supply and the drain valve to flush all linework from the oil outlet of the MP separator through the MP crude oil heater and on to the LP separator. Periodically OPEN the 1in isolation ball valve from the process inlet of the MP crude oil heater to the Skid Drip Pan to FLUSH the heater to the hazardous open drains.

Note: If heating medium is available, it will be beneficial to recommission the MP crude oil heater in order to heat the utility seawater during flushing. (26)

SHUT OFF the seawater supply to the crude outlet from the MP separator and DISCONNECT the supply hose. DRAIN the internals of the MP crude oil heater to the Skid Drip Pan. CLOSE the 1in isolation ball valve from the process inlet of the MP crude oil heater to the Skid Drip Pan on completion.

(27)

CLOSE the Isolation Ball Valve HV-10285 upstream of 10-LCV-0514 on the crude oil outlet from the Test separator. Also ENSURE that the 3in isolation ball valve HV-10289 for the bypass line is CLOSED. CONNECT a utility seawater supply hose to the drain point HV-10288 on the downstream side of 10-LCV-0514.

(28)

OPEN the isolation valve for the seawater supply and the drain valve to flush all linework from the outlet of the Test separator through the MP crude oil heater to the LP separator. It may be necessary to OPEN the 6in Isolation Ball Valve HV-10122 on the crude oil outlet from the Test separator to the MP crude oil heater and CLOSE the 6in Isolation Ball Valve HV-10077 on the crude oil outlet from the Test separator to the MP separator to divert the flushing water through the heater.

(29)

SHUT OFF the seawater supply to the crude outlet from the Test separator and DISCONNECT the supply hose once flushing is complete.


Page 20 / 105


Isolation/Reinstatement Procedures 6.01.4 Oil Processing Facilities, Flushing Operation Part 2 (Continued)

(30)

ENSURE that there is no pressure remaining in the LP separator by REMOVING the blank then carefully OPENING the vent valves fitted to the level gauge glasses for the vessel. OPEN the six 2in Isolation valves for the belly drains to drain the contents of the LP separator to the hazardous area open drain via the Skid Drip Pan. The hazardous area open drain header directs all flushings to the Port Hazardous Drains Collection Tank T-6001 for subsequent disposal. CLOSE the belly drains on completion.

(31)

CONNECT a suitable seawater hose to the purge/utility connection of the LP separator. OPEN the isolation valve on the seawater supply and the purge/utility connection valve to flood the vessel. OPEN the six 2in Isolation valves for the belly drains to drain the contents of the separator to the hazardous area open drain header. This will remove all liquid hydrocarbons from the vessel.

(32)

REMOVE the blank then connect a suitable seawater hose to the vent valve for oil/water Interface Level Gauge 10-LG-0316. OPEN the isolation valve for the seawater supply and the drain valve to flush the gauge to the hazardous area open drains.

(33)

FLUSH the following instrumentation for the LP separator to the hazardous area open drains: 

(34)

(35)


CONNECT a suitable seawater hose to the drain point on each produced water transfer pump suction line in turn: 

ENSURE that the manual isolation valve HV-10173/6 on the pump discharge line is OPEN to FLUSH back to the MP separator



CLOSE the drain valve HV-10172/5 on each produced water transfer pump suction line and DISCONNECT the flushing hose on completion

CONNECT a suitable seawater hose to the drain point on each crude oil transfer pump suction line in turn: 

FLUSH the pump suction line and minimum flowline back to the LP separator



ENSURE that the manual isolation valves HV-10168/9 on the pump discharge line are OPEN to flush through to the electrostatic coalescer



CLOSE the drain valve HV-10163/6 on each oil transfer pump suction line and DISCONNECT the flushing hose on completion


Page 21 / 105


Isolation/Reinstatement Procedures 6.01.4 Oil Processing Facilities, Flushing Operation Part 2 (Continued)

(36)

REMOVE the blank then connect a suitable seawater hose to the vent valve for electrostatic coalescer Oil/Water Interface Level Gauge 13-LG-0414. OPEN the isolation valve for the seawater supply and the vent valve to flush the level gauge to the hazardous area open drains.

(37)

FLUSH the following instrumentation for the electrostatic coalescer to the Hazardous Area Open Drain Header:

(38)



Tricock 1 at Nozzle N6A



Tricock 2 at Nozzle N6B



Tricock 3 at Nozzle N6C



Tricock 4 at Nozzle N6D



Tricock 5 at Nozzle N6E

ENSURE that there is no pressure remaining in the electrostatic coalescer then OPEN the 2in Isolation valve for the belly drain to drain the contents of the vessel to the hazardous area open drain header. CLOSE the belly drain valve on completion.

Note: All hydrocarbons have been previously removed from the coalescer by the jetting operations performed during the planned shutdown procedure. (39)

REMOVE the blank then CONNECT a suitable seawater hose to the high vent point HV-10226 for the crude inlet to the export crude oil cooler.

(40)

ENSURE that the 8in Isolation Ball Valve HV-10225 for the inlet to the export crude oil cooler is CLOSED and commence flushing the plate internals of the cooler.

(41)

Periodically OPEN the 1in Isolation Ball Valve HV-10228 from the crude outlet of the export crude oil cooler to the Skid Drip Pan to FLUSH the oil outlet from the electrostatic coalescer.

(42)

Once flushing is complete, SHUT OFF the seawater supply to the process inlet of the export crude oil cooler and DISCONNECT the supply hose.


Page 22 / 105


Isolation/Reinstatement Procedures 6.01.5 Oil Processing Facilities, Nitrogen Purging Operation

WARNING: ANY VENTING OF NITROGEN TO ATMOSPHERE SHOULD BE TREATED WITH EXTREME CARE, AS IN HIGH CONCENTRATIONS, INHALATION WILL CAUSE UNCONSCIOUSNESS ALMOST IMMEDIATELY. THEREFORE, NO CONTINUOUS VENTING OF EQUIPMENT SHOULD TAKE PLACE UNLESS IT IS TEMPORARILY PIPED TO A SUITABLE LOCATION WHERE PERSONNEL ARE NOT EXPOSED. With flushing operations complete, nitrogen purging operations of the oil processing facilities can commence. This is accomplished by purging each vessel and associated lines to flare, as described below. (1)

CHECK all local drain valves from the Oil Processing Facilities to the hazardous area open drains are CLOSED.

(2)

CLOSE the 10in Isolation Ball Valve on the inlet header from the Test Manifold to the Test separator.

(3)

CONNECT the nitrogen hose to the Purge Connection Point for the Test separator.

(4)

OPEN the 1in Isolation Ball Valves on the depressurisation line to the LP Flare.

(5)

OPEN the Isolation Valve for the Purge Connection Point and PURGE the Test separator to the LP Flare by displacement.

(6)

PERIODICALLY SAMPLE the purge gas in the Test separator from the vent valves provided for the level gauges. DISCONTINUE the Test separator purge when the hydrocarbon content is less than 0.25% (volume).

(8)

CLOSE, LOCK and TAG the 1in Isolation Ball Valves on the depressurisation line for the Test separator to the LP Flare.

Note: These valves form part of the Oil Processing Facilities Boundary Isolation Valve Checklist 6.01.6. (9)

CLOSE the 14in Isolation Ball Valve on the inlet header from the turret to the HP Separator.

(10)

CONNECT the nitrogen hose to the Purge Connection Point for the HP separator.

(11)

OPEN the 1in Isolation Ball Valves on the depressurisation line to the LP Flare.


Page 23 / 105



6.01.5 Oil Processing Facilities, Nitrogen Purging Operation (Continued)

(12)

OPEN the Isolation Valve for the Purge Connection Point and PURGE the HP separator to the LP Flare by displacement.

(13)

PERIODICALLY SAMPLE the purge gas in the HP separator from the vent valves provided for the level gauges. DISCONTINUE the HP separator purge when the hydrocarbon content is less than 0.25% (volume).

(14)

CLOSE, LOCK and TAG the 1in Isolation Ball Valves on the depressurisation line for the vessel to the LP Flare.


CLOSE the 8in Isolation Ball Valve on the inlet header from the Turret to the MP Separator.

(16)

CLOSE the 10in Isolation Ball Valve on the oil outlet line from the HP crude oil heater to the MP Separator.

(17)

CONNECT the nitrogen hose to the Purge Connection Point for the MP separator.

(18)

OPEN the 1in Isolation Valves on the bypass line for the interlocked Pressure Safety Relief Valves 10-PSV-0203A and B to the LP Flare.

(19)

OPEN the Isolation Valve for the Purge Connection Point and PURGE the MP separator to the LP Flare by displacement.

(19)

PERIODICALLY SAMPLE the purge gas in the MP separator from the vent valves provided for the level gauges. DISCONTINUE the MP separator purge when the hydrocarbon content is less than 0.25% (volume).

(20)

CLOSE, LOCK and TAG the 1in Isolation Ball Valves on the bypass line for the vessel pressure safety relief valves to the LP Flare.


CLOSE the 16in Isolation Ball Valve on the inlet line to the MP crude oil heater.

(22)

CONNECT the nitrogen hose to the Purge Connection Point for the LP separator.


Page 24 / 105



6.01.5 Oil Processing Facilities, Nitrogen Purging Operation (Continued)

(23)

OPEN the 1in Isolation Valves on the bypass line for the interlocked Pressure Safety Relief Valves 10-PSV-0303A and B to the LP Flare.

(24)

OPEN the Isolation Valve for the Purge Connection Point and PURGE the LP separator to the LP Flare by displacement.

(25)

PERIODICALLY SAMPLE the purge gas in the LP separator from the vent valves provided for the level gauges. DISCONTINUE the LP separator purge when the hydrocarbon content is less than 0.25% (volume).

(26)

CLOSE, LOCK and TAG the 1in Isolation Ball Valves on the bypass line for the vessel pressure safety relief valves to the LP Flare.


CLOSE the 8in Mix Valve on the inlet line to the electrostatic coalescer.

(28)

CONNECT the nitrogen hose to the Purge Connection Point for the electrostatic coalescer.

(29)

REMOVE the blank and CONNECT a hose suitable for purging operations to the vent point for the Level Gauge 10-LG-0414. ENSURE that the hose is routed to a safe area.

(30)

OPEN the Isolation Valve for the Purge Connection Point and PURGE the electrostatic coalescer to atmosphere by displacement.

(31)

PERIODICALLY SAMPLE the purge gas in the electrostatic coalescer from the vent valves provided for the level gauge. DISCONTINUE the purge when the hydrocarbon content is less than 0.25% (volume).

6.01.6 ID: M-CPH-1171-01417_EN_Section_6.doc

Page 25 / 105



Oil Processing Facilities Boundary Isolation Valve Checklist VALVE TAG No

LOCATION

LINE No

ISOLATED POSITION

SIG/ DATE

Refer to P&ID Nos CUR-MAS-TP-42002-001 and CUR-MAS-TP-42005-001 07-XXV-100

Well DP2 Riser ESD Valve

8in-F-07102-25SDB2-PG

CLOSED

-

Well DP1 Riser Low Point Drain Valve

N/A

CLOSED

-

Methanol Injection Double Block and Bleed Valve for Well DP2 Riser

1in-ME-73205-25DA

CLOSED

07-XV-105

Well DP2 Flowline ESD Valve

8in-F-07102-25SDB2-PG

CLOSED

-

Corrosion Inhibitor Injection Double Block and Bleed Valve for Well DP2 Flowline

1/4in-C-73228-25SSA3

CLOSED

-

Well DP2 Flowline Low Point Drain Valve

N/A

CLOSED

-

Flush point from Well DP2 Flowline to Test Separation Train

N/A

CLOSED

-

Flush point from Well DP2 Flowline to Production Separation Train

N/A

CLOSED

COMMENTS NOTE:

OPERATOR SIGNATURE: DATE:


Page 26 / 105



6.01.6 Oil Processing Facilities Boundary Isolation Valve Checklist (Continued) VALVE TAG No

LOCATION

LINE No

ISOLATED POSITION

07-XXV-200

Well DP1 Riser ESD Valve

8in-F-07202-25SDB2-PG

CLOSED

-

Well DP1 Riser Low Point Drain Valve

N/A

CLOSED

-

Methanol Injection Double Block and Bleed Valve for Well DP1 Riser

1in-ME-73204-25DA

CLOSED

07-XV-205

Well DP1 Flowline ESD Valve

8in-F-07202-25SDB2-PG

CLOSED

-

Corrosion Inhibitor Injection Double Block and Bleed Valve for Well DP1 Flowline

¼in-C-73229-25SSA3

CLOSED

-

Well DP1 Flowline Low Point Drain Valve

N/A

CLOSED

-

Flush point from Well DP1 Flowline to Test Separation Train

N/A

CLOSED

-

Flush point from Well DP1 Flowline to Production Separation Train

N/A

CLOSED

07-XXV-300

Well BP1 Riser ESD Valve

8in-F-07302-25DB2-PG

CLOSED

-

Well BP1 Riser Low Point Drain Valve

N/A

CLOSED

-

Methanol Injection Double Block and Bleed Valve for Well BP1 Riser

1in-ME-73206-25DA

CLOSED

SIG/ DATE

COMMENTS NOTE: OPERATOR SIGNATURE: DATE:


Page 27 / 105




LOCATION

LINE No

ISOLATED POSITION

07-XV-305

Well BP1 Flowline ESD Valve

8in-F-07302-25DB3-PG

CLOSED

-

Corrosion Inhibitor Injection Double Block and Bleed Valve for Well BP1 Flowline

¼in-C-73227-25SSA3

CLOSED

-

Well BP1 Flowline Low Point Drain Valve

N/A

CLOSED

-

Flush point from Well BP1 Flowline to Test Separation Train

N/A

CLOSED

-

Flush point from Well BP1 Flowline to Production Separation Train

N/A

CLOSED

Spare Well Riser ESD Valve

12in-F-07552-K15CSC1TPFP

CLOSED

Spare Well Riser Low Point Drain Valve

N/A

CLOSED

Spare Well Flowline ESD Valve

12in-F-07553-K15CSC2HC

CLOSED

Spare Well Flowline Low Point Drain Valve

N/A

CLOSED

Spectacle blind on Spare Well Flowline to Test Separation Train

N/A

CLOSED

Spectacle blind on Spare Well Flowline to Production Separation Train

N/A

CLOSED

Spectacle blind on Spare Well Flowline to Water Injection Swivel

N/A

CLOSED

SIG/ DATE

Refer to P&ID No CUR-MAS-TP-42035-001 07-XXV-0500

07-XV-0505


Page 28 / 105



6.01.6 Oil Processing Facilities Boundary Isolation Valve Checklist (Continued) LOCATION ISOLATED VALVE LINE No POSITION

TAG No

SIG/ DATE

Refer to P&ID Nos CUR-MASPM-20048-501 and CUR-MASPB-20048-002 HV-73007

Isolation valve for demulsifier to the Test separator inlet manifold

1in-C-73514-D6A

CLOSED

HV-73009

Isolation valve for defoamer to the Test separator inlet manifold

1in-C-73522-D6A

CLOSED

3in-V-10003-HB7A

CLOSED

10-XV-0501

Blowdown valve for the Test separator

COMMENTS NOTE:



Page 29 / 105



6.01.6 Oil Processing Facilities, Boundary Isolation Valve Checklist (Continued) VALVE TAG No

LOCATION

LINE No

ISOLATED POSITION

HV-10239

Downstream isolation valve for 10-XV-0501

8in-V-10-003-HB7A

CLOSED

HV-10237

1st in-line isolation valve for Test separator depressurisation line

1in-V-10005-HB7A

CLOSED

HV-10236

2nd in-line isolation valve for Test separator depressurisation line

1in-V-10005-HB7A

CLOSED

HV-10235

3rd in-line isolation valve for Test separator depressurisation line

1in-V-10005-HB7A

CLOSED

HV-10238

Vent valve for Test separator depressurisation line

1in-V-10005-HB76A

CLOSED

HV-10243/4

Downstream isolation valve for 10-PSV-0503A

10in-V-10002-HA6A

CLOSED

HV-10248/9

Downstream isolation valve for 10-PSV-0503B

10in-V-10002-HA6A

CLOSED

HV-10251

1st in-line isolation valve for PSV bypass line

1in-V-10-001-HB7A

CLOSED

HV-10250

2nd in-line isolation valve for PSV bypass line

1in-V-10-001-HB7A

CLOSED

HV-10255

1st in line isolation valve for gas outlet sample point

N/A

CLOSED

SIG/ DATE

COMMENTS NOTE:

OPERATOR SIGNATURE: DATE: ID: M-CPH-1171-01417_EN_Section_6.doc

Page 30 / 105




LOCATION

LINE No

ISOLATED POSITION

HV-10256

2nd in-line isolation valve for gas outlet sample point

N/A

CLOSED

HV-10253/4

Downstream isolation valve for 10-PCV-0507B for the gas outlet from Test separator to the HP Flare

10in-V-10006-HA6A

CLOSED

HV-10258/9

Downstream isolation valve for 10-PCV-0507A for the gas outlet from Test separator to the inlet cooler

10in-G-10-001-HB7A-PG

CLOSED

HV-10283

1st in-line isolation valve for crude outlet sample point

N/A

CLOSED

HV-10284

2nd in-line isolation valve for crude outlet sample point

N/A

CLOSED

HV-10281

Isolation ball valve on Test separator produced water outlet to test/HP hydrocyclone package

4in-WP-10001-B2DHC25

HV-10273

Jetting Water Valve 1

1in-WW-10001-HB2D

CLOSED

HV-10275


1in-WW-10001-HB2D

CLOSED

HV-10277


1in-WW-10001-HB2D

CLOSED

HV-10278

Jetting water outlet valve to skid drip pan

1in-D-10005-HA1C

CLOSED

SIG/ DATE

CLOSED

COMMENTS NOTE:



Page 31 / 105



6.01.6 Oil Processing Facilities Boundary Isolation Valve Checklist (Continued) VALVE TAG No 20-XV-1191

LOCATION

LINE No

Shutdown valve for the Test separator Gas outlet

ISOLATED POSITION

10in-G-20506-B7A-PG

CLOSED

SIG/ DATE


Isolation valve for demulsifier to the HP separator inlet manifold

1in-C-73512-D6A

CLOSED

HV-73002

Isolation valve for defoamer to the HP separator inlet manifold

1in-C-73520-D6A

CLOSED

10-XV-0101

Blowdown valve for the HP separator

HV-10033

HV-10015

HV-10017

CLOSED 4in-V-10009-HB7A

Downstream isolation valve for 10-XV-0101 1st in-line isolation valve for HP separator depressurisation line 2nd in-line isolation valve for HP separator depressurisation line

CLOSED 10in- V-10009-HB7A CLOSED 1in-V-10011-HB7A CLOSED 1in-V-10011-HB7A

HV-10018

3rd in-line isolation valve for HP separator depressurisation line

1in-V-10011-HB7A

CLOSED

HV-10016

Vent isolation valve for HP separator depressurisation line

1in-V-10011-HB7A

CLOSED

COMMENTS NOTE:


Page 32 / 105



6.01.6 Oil Processing Facilities, Boundary Isolation Valve Checklist (Continued) VALVE TAG No HV-10023/4

HV-10029/30

HV-10032

HV-10031

LOCATION

LINE No

Downstream isolation valve for 10-PSV-0103A Downstream isolation valve for 10-PSV-0103B 1st in-line isolation valve for PSV bypass line 2nd in-line isolation valve for PSV bypass line

ISOLATED POSITION CLOSED

10in-V-10008-HA6A CLOSED 10in-V-10008-HA6A CLOSED 1in-V-10007-HB7A CLOSED 1in-V-10007-HB7A

HV-10021

1st in-line isolation valve for gas outlet sample point

N/A

CLOSED

HV-10027


N/A

CLOSED

HV-10049


N/A

CLOSED

HV-10050

2nd in-line isolation valve for crude outlet sample point

N/A

CLOSED

HV-10046

Isolation ball valve on HP separator produced water outlet to HP/Test hydrocyclone package

6in-WP-10002-B7A-HC25


1in-WW-10002-HB2D

HV-10037

SIG/ DATE

CLOSED

CLOSED

COMMENTS NOTE:


Page 33 / 105




LOCATION

LINE No

ISOLATED POSITION

HV-10039


1in-WW-10002-HB2D

CLOSED

HV-10041


1in-WW-10002-HB2D

CLOSED

HV-10043


1in-WW-10002-HB2D

CLOSED

HV-10060


1in-WW-10002-HB2D

CLOSED

HV-22001

Downstream isolation valve for 10-PCV-0107 on the gas outlet line from the HP separator to the HP Flare

14in-G-50526-A6A-PG

CLOSED

HV-52001

Isolation valve for the gas outlet line from the HP separator to the Fuel Gas Cooler

4in-GF-52516-B7A-PG

CLOSED

22-XV-1051

Shutdown valve for the HP separator Gas outlet

10in-G-10-22501-B7A-PG

CLOSED

22-XV-1052

Bypass valve for the HP separator Gas outlet

2in-G-10-22501-B7A-PG

CLOSED

HV-22002

Isolation valve for the gas outlet from the HP separator Gas to the inlet gas cooler

10in-G-10-22501-B7A-PG

CLOSED

SIG/ DATE

COMMENTS NOTE:

OPERATOR SIGNATURE: DATE: 6.01.6 Oil Processing Facilities, Boundary Isolation Valve Checklist (Continued) ID: M-CPH-1171-01417_EN_Section_6.doc

Page 34 / 105


Isolation/Reinstatement Procedures VALVE TAG No

LOCATION

LINE No

ISOLATED POSITION

SIG/ DATE

Refer to P&ID No CUR-MAS-PM20042-501 HV-44054

Isolation valve for the Heating Medium supply to the HP crude oil heater

4in-HM-44001-HA1CHC50

CLOSED

HV-44063

Isolation valve for the Heating Medium return from the HP crude oil heater


CLOSED

HV-10067

Downstream isolation valve for 10-PSV-0153

CLOSED 2in-V-10012-HAGA


Isolation valve for demulsifier to the MP separator inlet manifold

1in-C-73513-D6A

CLOSED

HV-73006

Isolation valve for defoamer to the MP separator inlet manifold

1in-C-73521-D6A

CLOSED

10-XV-0201

Blowdown valve for the MP separator

CLOSED 4in-V-10015-HA2D COMMENTS

NOTE:



Page 35 / 105




LOCATION

LINE No

ISOLATED POSITION

HV-10079


12in-V-10005-HA20

CLOSED

HV-10083


8in-V-10004-HA1C

CLOSED

HV-10086


8in-V-10004-HA1C

CLOSED

HV-10088

1st in-line isolation valve for PSV bypass line

1in-V-10013-HA2D

CLOSED

HV-10087


1in-V-10013-HA2D

CLOSED

HV-10091


N/A

CLOSED

HV-10092


N/A

CLOSED

HV-10090

Downstream isolation valve for 10-PCV-0207B for the gas outlet from MP separator to the LP Flare

8in-V-10017-HA1C

CLOSED

HV-10116


N/A

CLOSED

HV-10117

2nd in-line isolation valve for crude N/A outlet sample point

CLOSED

SIG/ DATE

COMMENTS NOTE:


Page 36 / 105



6.01.6 Oil Processing Facilities, Boundary Isolation Valve Checklist (Continued) VALVE TAG No HV-10112

LOCATION

LINE No

ISOLATED POSITION

SIG/ DATE

CLOSED

Isolation ball valve on MP separator produced water outlet to MP hydrocyclone package

6in-WP-10003-HA1EHC25

HV-10102


1in-WW-10003-HA2D

CLOSED

HV-10104


1in-WW-10003-HA2D

CLOSED

HV-10106


1in-WW-10003-HA2D

CLOSED

HV-10108


1in-WW-10003-HA2D

CLOSED

HV-10110


1in-WW-10003-HA2D

CLOSED

HV-10115

Jetting water drain outlet to skid drip pan

1in-D-10024-HA1C

CLOSED

20-XV-1201

Shutdown valve for the MP separator Gas outlet

10in-G-20502-B2D-PG

CLOSED

20-XV-1202

Bypass valve for the MP separator Gas outlet

2in-G-22502-B2D-PG

CLOSED

COMMENTS NOTE:


Page 37 / 105




LOCATION

LINE No

ISOLATED POSITION

SIG/ DATE

Refer to P&ID Nos CUR-MASPB-20122-001 HV-22039

22-LCV-0009 downstream block 4in-P-10551-A2D-HT valve on Condensate outlet line from Glycol Contactor C-2201 to the MP Separator

CLOSED

HV-22038

Bypass valve around 22-LCV-0009

3in-P-10551-A2D-HT

CLOSED

Refer to P&ID Nos CUR-MASPB-20131-001 HV-10007

20-LCV-1135 downstream block valve on Condensate outlet line from Export Gas Scrubber V-2001 to the MP Separator

2in-P-10552-A2D

CLOSED

HV-10006

Bypass valve around 20-LCV-1135

1in-P-10552-A2D

CLOSED

COMMENTS NOTE:


Page 38 / 105




LOCATION

LINE No

ISOLATED POSITION

SIG/ DATE

Refer to P&ID No CUR-MASPB-20112-001 HV-20012

Isolation Ball Valve for LP Suction Scrubber Pump P-2002A discharge to the MP crude oil heater

2in-P-20601-A2D-HT

CLOSED

HV-20015

Isolation Ball Valve for LP Suction Scrubber Pump P-2002B discharge to the MP crude oil heater

2in-P-20601-A2D-HT

CLOSED


Downstream isolation valve for 20-LCV-1096 on the liquid outlet from the MP suction scrubber to the MP crude oil heater

4in-P-10553-A2D-HT

CLOSED

HV20074

Isolation valve for 20-LCV-1096 bypass line

3in-P-10553-A2D-HT

CLOSED

2in-P-10556-A2D-HT

CLOSED


Isolation Ball Valve for HP Flare KO Drum Pump P-5001A discharge to the MP crude oil heater

COMMENTS NOTE:


Page 39 / 105



6.01.6 Oil Processing Facilities Boundary Isolation Valve Checklist (Continued) VALVE TAG No HV-10009

LOCATION

LINE No

Isolation Ball Valve for HP Flare KO Drum Pump P-5001B discharge to the MP crude oil heater

ISOLATED POSITION

2in-P-10556-A2D-HT

CLOSED

SIG/ DATE


Isolation Ball Valve for LP Flare KO Drum Pump P-5101A discharge to the MP crude oil heater

2in-P-10557-A2D-HT

CLOSED

HV-10011

Isolation Ball Valve for LP Flare KO Drum Pump P-5101B discharge to the MP crude oil heater

2in-P-10557-A2D-HT

CLOSED

2in-P-10558-B2D

CLOSED

Refer to P&ID Nos CUR-MASPB-20044-002 10-XV-1081

Shutdown valve for the liquids outlet from the fuel gas scrubber to the MP crude oil heater

COMMENTS NOTE:



Page 40 / 105




LOCATION

LINE No

ISOLATED POSITION

SIG/ DATE

Refer to P&ID Nos CUR-MASPM-20044-501 HV-44064

Isolation valve for the Heating Medium supply to the MP crude oil heater


CLOSED

Refer to P&ID No CUR-MASPM-20051-501 HV-40003

Isolation Valve downstream of 40-PCV-0101 on oil reject line from the HP hydrocyclone to the MP crude oil heater

2in-WP-40102-HA1E-HT

CLOSED

HV-40006

Isolation Valve on 40-PCV-0101 bypass line


CLOSED


Isolation Valve downstream of 40-PCV-0201 on oil reject line from the MP hydrocyclone to the MP crude oil heater


CLOSED

HV-40024



CLOSED


Isolation Valve downstream of 40-PCV-0301 on oil reject line from the test hydrocyclone to the MP crude oil heater


CLOSED

HV-40040



CLOSED

COMMENTS NOTE: OPERATOR SIGNATURE: DATE:


Page 41 / 105




LOCATION

LINE No

ISOLATED POSITION

HV-44063

Isolation valve for the Heating Medium return from the HP crude oil heater


CLOSED

HV-10126

Downstream isolation valve for 10-PSV-0253

3in-V-10018-HA1C

CLOSED

SIG/ DATE

Refer to P&ID Nos CUR-MASPM-20045-501 10-XV-0301

Blowdown valve for the LP separator

4in-V-10021-HA2D

CLOSED

HV-10135


10in-V-10022-HA1C

CLOSED

HV-10129


10in-V-10020-HA1C

CLOSED

HV-10132


10in-V-10020-HA1C

CLOSED

HV-10134

1st in-line isolation valve for PSV 1in-V-10019-HA2D bypass line

CLOSED

HV-10133


1in-V-10019-HA2D

CLOSED

HV-10138


N/A

CLOSED

HV-10139


N/A

CLOSED

COMMENTS NOTE:



Page 42 / 105




LOCATION

LINE No

ISOLATED POSITION

HV-10136

Downstream isolation valve for 10-PCV-0307B for the gas outlet from LP separator to the LP Flare

14in-V-10023-HA1C

CLOSED

HV-10160


N/A

CLOSED

HV-10161

2nd in-line isolation valve for crude N/A outlet sample point

CLOSED

HV-10140


1in-WW-10004-HA2D

CLOSED

HV-10142


1in-WW-10004-HA2D

CLOSED

HV-10144


1in-WW-10004-HA2D

CLOSED

HV-10146


1in-WW-10004-HA2D

CLOSED

HV-10148


1in-WW-10004-HA2D

CLOSED

HV-10170

Jetting water outlet drain valve to skid drip pan

1in-D-10034-HA1C

CLOSED

16in-G-20503-A2D-PG

CLOSED

SIG/ DATE

Refer to P&ID Nos CUR-MAS-PB20045-002 20-XV-1221

Shutdown valve for the LP separator Gas outlet

COMMENTS NOTE:


Page 43 / 105




LOCATION

LINE No

ISOLATED POSITION

SIG/ DATE



CLOSED 8in-V-10024-HA1C

HV-10184


8in-V-10024-HA1C

CLOSED

HV-10208

Isolation valve to Tricock Cooler for sample line at Nozzle N6A

½in-D-10048-HA2DHC25

CLOSED

HV-10213

Isolation valve from Tricock Cooler for sample line at Nozzle N6A


CLOSED

HV-10209

Isolation valve to Tricock Cooler for sample line at Nozzle N6B


CLOSED

HV-10214

Isolation valve from Tricock Cooler for sample line at Nozzle N6B


CLOSED

HV-10210

Isolation valve to Tricock Cooler for sample line at Nozzle N6C


CLOSED

HV-10215

Isolation valve from Tricock Cooler for sample line at Nozzle N6C


CLOSED

HV-10211

Isolation valve to Tricock Cooler for sample line at Nozzle N6D


CLOSED

COMMENTS NOTE:



Page 44 / 105




LOCATION

LINE No

ISOLATED POSITION

HV-10216

Isolation valve from Tricock Cooler for sample line at Nozzle N6D


CLOSED

HV-10212

Isolation valve to Tricock Cooler for sample line at Nozzle N6E


CLOSED

HV-10217

Isolation valve from Tricock Cooler for sample line at Nozzle N6E


CLOSED

HV-10197

Drain Valve No 1 for coalescer bushings at Nozzle N5A

¾in -D-10042-HA1C

CLOSED

HV-10198

Drain Valve No 2 for coalescer bushings at Nozzle N5A

¾in-D-10041-HA1C

CLOSED

HV-10201

Drain Valve No 1 for coalescer bushings at Nozzle N5B

¾in -D-10040-HA1C

CLOSED

HV-10202

Drain Valve No 2 for coalescer bushings at Nozzle N5B

¾in -D-10041-HA1C

CLOSED

6in-CM-45001-HA1C

CLOSED

SIG/ DATE


Isolation valve for the Cooling Medium supply to the export crude oil cooler

COMMENTS NOTE:



Page 45 / 105




LOCATION

LINE No

ISOLATED POSITION

HV-45101

Isolation valve for the Cooling Medium return from the export crude oil cooler

6in-CM-45002-HA1C

CLOSED

10-XV-0458

Shutdown valve for the crude oil outlet from the export crude oil cooler

8in-F-10015-HA2D

CLOSED

SIG/ DATE

COMMENTS NOTE:



Page 46 / 105



6.02 Test Separator V-1005





The boundary isolations for the oil processing facilities are in place, and the Test separator has been flushed, drained and nitrogen purged, as described in Section 6.01 of this volume



This vessel entry procedure is undertaken within the oil facilities boundary isolations as listed under the Boundary Isolation Valve Checklist



Prior to vessel entry, the Test separator requires to be physically disconnected from the associated pipework by either the rotation of spectacle blinds or the removal of maintenance spools within the process side blinded with correctly rated blind flanges



It is assumed that the pressure safety relief valves for the Test separator will be removed for certification. The flare side flanges for the relief valves must be isolated by suitably rated blind flanges



Prior to vessel entry, the hydrocarbon and nitrogen gases must be displaced until the atmosphere within the vessel contains 21% oxygen and less than 0.25% (volume) hydrocarbons

WARNING: ANY VENTING OF NITROGEN TO ATMOSPHERE SHOULD BE TREATED WITH EXTREME CARE, AS IN HIGH CONCENTRATIONS INHALATION WILL CAUSE UNCONSCIOUSNESS ALMOST IMMEDIATELY. NO LOCAL CONTINUOUS VENTING OF EQUIPMENT SHOULD TAKE PLACE UNLESS IT IS PIPED TO A SUITABLE LOCATION WHERE PERSONNEL ARE NOT EXPOSED. 

While a nitrogen atmosphere remains within the vessel, any work entailing the splitting of pipe flanges (turning of spectacled blinds etc) may require to be undertaken with personnel wearing positive pressure Breathing Apparatus sets



This procedure should be used in conjunction with Spading Checklist, V-1005 and marked up P&ID CUR-MAS-PM-20048-501, included at the end of this procedure


Page 47 / 105



6.02.2 Preparation for Vessel Entry Procedure

(1)

REMOVE the blanks then carefully OPEN the vent valves for the level gauges fitted to the vessel. This will ENSURE that there is no pressure trapped in the Test separator.

Note: Any remaining gases in the Test separator must be vented to a safe area suitable for the disposal of hydrocarbon gases. (2)

SWING Spectacled Blind SB1 on the inlet header to the CLOSED position.

(3)

SWING Spectacled Blind SB2 on the gas outlet line to the CLOSED position.

(4)

SWING Spectacled Blind SB3 on the oil outlet line to the CLOSED position.

(5)

SWING Spectacled Blind SB4 on the produced water outlet line to the CLOSED position.

(6)

SWING Spectacled Blind SB6 on the Belly Drain line at Nozzle N6 to the CLOSED position.

(7)

DIVIDE the Sandwash line at Nozzle N10A and INSERT Spade S10A to the flange faces.

(8)

DIVIDE the Sandwash line at Nozzle N10B and INSERT Spade S10B to the flange faces.

(9)

DIVIDE the Sandwash line at Nozzle N10C and INSERT Spade S10C to the flange faces.

(10)

DIVIDE the Belly Drain line at Nozzle N11A and SWING Spectacle Blind SB11A to the CLOSED position.

(11)

DIVIDE the Belly Drain line at Nozzle N11B and SWING Spectacle Blind SB11B to the CLOSED position.

(12)

DIVIDE the Belly Drain line at Nozzle N11C and SWING Spectacle Blind SB11C to the CLOSED position.

(13)

SWING Spectacle Blind SB7A on the Blowdown line to the CLOSED position.

(14)

SWING Spectacle Blind SB7B on the Manual Depressurisation line to the CLOSED position.

(15)

DIVIDE the Relief line at Nozzle N8 and INSERT Spade S8 to the flange faces.


Page 48 / 105



6.02.2 Preparation for Vessel Entry Procedure (Continued)

(16)

OPEN the Vessel Access Hatches M1A and M1B installed at the ends of the separator.

(17)

POSITION an air mover within each vessel access hatch ENSURING the exhaust ducting vents are led away to a safe area.

(18)

Use the air mover to displace the gases within the separator until the atmosphere inside the vessel contains 21% oxygen and less than 0.25% hydrocarbons.

(19)

If the Pressure Relief Valves 10-PSV-0503A and B are to be removed for recertification, the flare pipework must be blinded off using Blind Flanges BF12 and BF13 and included on Spading Checklist V-1005.

Note: Ensure the open-ended pipework on the relief line from the Test separator are blanked off once the pressure safety relief valves are removed. (20)

The Test separator is available for entry when the appropriate Vessel Entry Permit has been issued.


Page 49 / 105



6.02.3 Reinstatement Procedure

Note: Flanges that have been disturbed must have new replacement gaskets of the correct specification installed. (1)

(2)

CONFIRM that all equipment has been removed from the vessel and the internal trim is in place and secure. CLOSE the Access Hatch Doors M1A and M1B.

(3)

RECONFIRM the boundary isolations on the Boundary Isolation Checklist before removing any blind flanges or turning spectacled blinds.

(4)

SWING Spectacled Blind SB1 on the inlet header to the OPEN position.

(5)

SWING Spectacled Blind SB2 on the gas outlet line to the OPEN position.

(6)

SWING Spectacled Blind SB3 on the oil outlet line to the OPEN position.

(7)

SWING Spectacled Blind SB4 on the produced water outlet line to the OPEN position.

(8)

SWING Spectacled Blind SB6 on the Belly Drain line at Nozzle N6 to the OPEN position.

(9)

DIVIDE the Sandwash line at Nozzle N10A and REMOVE Spade S10A then MAKE UP the flange faces.

(10)

DIVIDE the Sandwash line at Nozzle N10B and REMOVE Spade S10B then MAKE UP the flange faces.

(11)

DIVIDE the Sandwash line at Nozzle N10C and REMOVE Spade S10C then MAKE UP the flange faces.

(12)

DIVIDE the Belly Drain line at Nozzle N11A and SWING SB11A to the OPEN position then MAKE UP the flange faces.

(13)

DIVIDE the Belly Drain line at Nozzle N11B and SWING SB11B to the OPEN position then MAKE UP the flange faces.

(14)

DIVIDE the Belly Drain line at Nozzle N11C and SWING SB11C to the OPEN position then MAKE UP the flange faces.

(15)

SWING Spectacled Blind SB7A on the Blowdown line to the OPEN position.

(16)

SWING Spectacled Blind SB7B on the Manual Depressurisation line to the OPEN position.


Page 50 / 105


Isolation/Reinstatement Procedures 6.02.3 Reinstatement Procedure (Continued)

(17)

DIVIDE the Relief line at Nozzle N8 and REMOVE Spade S8 then MAKE UP the flange faces.

(18)

If the Pressure Relief valves 10-PSV-0503A and B have been removed for recertification, REMOVE Blind Flanges BF12 and BF13 from the flare side pipe flanges and REFIT the relief valves.

The Test separator, V-1005 has now been reinstated. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary.


Page 51 / 105


Isolation/Reinstatement Procedures 6.02.4 Spading Checklist V-1005 BLIND No

LOCATION

LINE No

SB1

Nozzle N1

10in-F-10001-HB2D-PG

SB2

Nozzle N2

10in-G-10001-HB7A-PG

SB3

Nozzle N3

6in-F-10002-HB2D-PG

SB4

Nozzle N4

4in-WP-10001-B2D-HC25

SB6

Nozzle N6

2in-D-10004-HA1C

SB7A

Blowdown Line

8in-V-10003-HB7A

SB7B

Depressurisation Line

1in-V-10005-HB7A

Nozzle N8

4in-V-10001-HB7A

S10A

Nozzle N10A

1in-WW-10001-HB2D

S10B

Nozzle N10B

1in-WW-10001-HB2D

S10C

Nozzle N10C

1in-WW-10001-HB2D

S8

SB11A Nozzle N11A

2in-D-10001-HA1C

SB11B Nozzle N11B

2in-D-10002-HA1C

DATE FITTED

SIG

DATE PULLED

SIG

COMMENTS BF = Blind Flange SB = Spectacled Blind S = Spade



Page 52 / 105


Isolation/Reinstatement Procedures 6.02.4 Spading Checklist V-1005 (Continued) BLIND No SB11C

LOCATION

LINE No

Nozzle N11C

2in-D-10003-HA1C

BF12

13-PSV-0503A

6in-V-10002-HA6A

BF13

13-PSV-0503B

6in-V-10002-HA6A

DATE FITTED

SIG

DATE PULLED

SIG




Page 53 / 105


Isolation/Reinstatement Procedures 6.03 HP Separator V-1001





The boundary isolations for the oil processing facilities are in place, and the HP separator has been flushed, drained and nitrogen purged, as described in Section 6.01 of this volume






Prior to vessel entry the HP separator requires to be physically disconnected from the associated pipework by either the rotation of spectacle blinds or the removal of maintenance spools within the process side blinded with correctly rated blind flanges



It is assumed that the pressure safety relief valves for the HP separator will be removed for certification. The flare side flanges for the relief valves must be isolated by suitably rated blind flanges










Page 54 / 105




(1)

REMOVE the blanks then carefully OPEN the vent valves for the level gauges fitted to the vessel. This will ENSURE that there is no pressure trapped in the HP separator.

Note: Any remaining gases in the HP separator must be vented to a safe area suitable for the disposal of hydrocarbon gases. (2)


(3)


(4)


(5)


(6)

DIVIDE the Belly Drain line at Nozzle N6 and SWING Spectacle Blind SB6 to the CLOSED position.

(7)


(8)


(9)


(10)

DIVIDE the Sandwash line at Nozzle N10D and INSERT Spade S10D to the flange faces.

(11)

DIVIDE the Sandwash line at Nozzle N10E and INSERT Spade S10E to the flange faces.

(12)

DIVIDE the Belly Drain line at Nozzle N11A and SWING Spectacle Blind SB11A to the CLOSED position.

(13)

DIVIDE the Belly Drain line at Nozzle N11B and SWING Spectacle Blind SB11B to the CLOSED position.

(14)

DIVIDE the Belly Drain line at Nozzle N11C and SWING Spectacle Blind SB11C to the CLOSED position.


Page 55 / 105




(15)

DIVIDE the Belly Drain line at Nozzle N11D and SWING Spectacle Blind SB11D to the CLOSED position.

(16)

DIVIDE the Belly Drain line at Nozzle N11E and SWING Spectacle Blind SB11E to the CLOSED position.

(17)

SWING Spectacle Blind SB7A on the Blowdown line to the CLOSED position.

(18)

SWING Spectacle Blind SB7B on the Manual Depressurisation line to the CLOSED position.

(19)


(20)


(21)


(22)


(23)


Note: Ensure that the open-ended pipework on the relief line from the HP separator are blanked off once the pressure safety relief valves are removed. (24)

The HP separator is available for entry when the appropriate Vessel Entry Permit has been issued.


Page 56 / 105





(2)


(3)


(4)


(5)


(6)


(7)


(8)

DIVIDE the Belly Drain line at Nozzle N6 and SWING Spectacle Blind SB6 to the OPEN position.

(9)


(10)


(11)


(12)

DIVIDE the Sandwash line at Nozzle N10D and REMOVE Spade S10D then MAKE UP the flange faces.

(13)

DIVIDE the Sandwash line at Nozzle N10E and REMOVE Spade S10E then MAKE UP the flange faces.

(14)

DIVIDE the Belly Drain line at Nozzle N11A and SWING SB11A to the OPEN position, then MAKE UP the flange faces.

(15)

DIVIDE the Belly Drain line at Nozzle N11B and SWING SB11B to the OPEN position then MAKE UP the flange faces.


Page 57 / 105



6.03.3 Reinstatement Procedure (Continued)

(16)

DIVIDE the Belly Drain line at Nozzle N11C and SWING SB11C to the OPEN position then MAKE UP the flange faces.

(17)

DIVIDE the Belly Drain line at Nozzle N11D and SWING SB11D to the OPEN position then MAKE UP the flange faces.

(18)

DIVIDE the Belly Drain line at Nozzle N11E and SWING SB11E to the OPEN position then MAKE UP the flange faces.

(19)

SWING Spectacled Blind SB7A on the Blowdown line to the OPEN position.

(20)

SWING Spectacled Blind SB7B on the Manual Depressurisation line to the OPEN position.

(21)


(22)


The HP separator, V-1001 has now been reinstated. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary.


Page 58 / 105



LOCATION

LINE No

SB1

Nozzle N1

14in-F-10004-HB2D-PG

SB2

Nozzle N2

12in-G-10003-HB7A-PG

SB3

Nozzle N3

6in-F-10005-HB2D-PG

SB4

Nozzle N4

6in-WP-10002-HB1EHC25

SB6

Nozzle N6

2in-D-10013-HA1C

SB7A

Blowdown Line

10in-V-10008-HB7A

SB7B

Depressurisation Line

1in-V-10011-HB7A

Nozzle N8

6in-V-10007-HB7A

S10A

Nozzle N10A

1in-WW-10002-HB2D

S10B

Nozzle N10B

1in-WW-10002-HB2D

S10C

Nozzle N10C

1in-WW-10002-HB2D

S10D

Nozzle N11A

1in-WW-10002-HB2D

S10E

Nozzle N11B

1in-WW-10002-HB2D

S8

DATE FITTED

SIG

DATE PULLED

SIG




Page 59 / 105



6.03.4 Spading Checklist V-1001 (Continued) BLIND No

LOCATION

LINE No

SB11A

Nozzle N11A

2in-D-10008-HA1C

SB11B

Nozzle N11B

2in-D-10009-HA1C

SB11C

Nozzle N11C

2in-D-10010-HA1C

SB11D

Nozzle N11D

2in-D-100011-HA1C

SB11E

Nozzle N11E

2in-D-10012-HA1C

BF12

10-PSV-0103A

8in-V-10008-HA6A

BF13

10-PSV-0103B

8in-V-10008-HA6A

DATE FITTED

SIG

DATE PULLED

SIG




Page 60 / 105



6.04 HP Crude Oil Heater E-1001





The boundary isolations for the oil processing facilities are in place, and the HP crude oil heater has been flushed and drained, as described in Section 6.01 of this volume



This procedure is undertaken within the oil facilities boundary isolations as listed under the Boundary Isolation Valve Checklist



This procedure is written with the viewpoint that the HP crude oil heater has been shut down as part of the overall oil processing facilities shutdown. When the Curlew production wells are flowing to the Oil Processing Facilities, the HP crude oil heater is normally in constant use to heat the crude oil passing from the HP separator to the MP separator



The following procedure describes the mechanical isolation (spading) required for boundary situations



It is assumed that the Pressure Safety Relief Valve 10-PSV-0153 for the crude outlet from the HP crude oil heater will be removed for certification. The flare side flange on the relief line must be isolated by a suitably rated blind flange



If Pressure Safety Relief Valve 44-PSV-2013 for the heating medium return from the heater is to be removed for certification the inlet flange must be blanked off once the valve is removed



This procedure should be used in conjunction with the Boundary Isolation Valve Checklist, Spading Checklist E-1001 and marked up P&ID CUR-MAS-PM-20042-501, included at the end of this procedure


Page 61 / 105



6.04.2 Isolation Procedure

(1)

Carefully OPEN the drain valve for the crude inlet to the HP crude oil heater. This will ENSURE that there is no pressure trapped in the tubeside of the heater.

Note: Any remaining drainings from the tubeside of the heater must be directed to the skid drip pan, which is suitable for the disposal of liquid hydrocarbons. (2)

SWING Spectacled Blind SB1 on the crude inlet to the CLOSED position.

(3)

SWING Spectacled Blind SB2 on the crude outlet to the CLOSED position.

(4)

Carefully OPEN the drain valve for the heating medium outlet from the HP crude oil heater. This will ENSURE that there is no pressure trapped in the shellside of the heater.

Note: Any remaining drainings from the shellside of the heater must be directed to the skid drip pan, which is suitable for the disposal of heating medium. (5)

SWING Spectacled Blind SB3 on the heating medium inlet to the CLOSED position.

(6)

SWING Spectacled Blind SB4 on the heating medium outlet to the CLOSED position.

(7)

If the Pressure Safety Relief Valve 10-PSV-0153 for the crude outlet is to be removed for recertification, the flare pipework must be blinded off using Blind Flange BF5 and included on Spading Checklist E-1001.

(6)

If the Pressure Safety Relief Valve 44-PSV-2013 for the heating medium return is to be removed for recertification, the flare pipework must be blinded off using Blind Flange BF6 and included on Spading Checklist E-1001.

Note: Ensure that the open-ended pipework on the crude and heating medium outlets from the HP crude oil heater are blanked off once the pressure safety relief valves are removed.


Page 62 / 105






(2)

SWING Spectacled Blind SB1 on the crude inlet to the OPEN position.

(3)

SWING Spectacled Blind SB2 on the crude outlet to the OPEN position.

(4)

SWING Spectacled Blind SB3 on the heating medium inlet to the OPEN position.

(5)

SWING Spectacled Blind SB4 on the heating medium outlet to the OPEN position.

(6)

If the Pressure Safety Relief Valve, 10-PSV-0153 has been removed for recertification, REMOVE Blind Flange BF5 on the flare side pipe flange and REFIT the relief valve.

(7)


(8)

ENSURE that the drain valves for the crude inlet and heating medium outlet lines are CLOSED.

The HP Crude Oil Heater, E-1001 has now been reinstated. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary.


Page 63 / 105


Isolation/Reinstatement Procedures 6.04.4 Spading Checklist E-1001 BLIND No

LOCATION

LINE No

SB1

Crude oil inlet

6in-F-10005-HB2D-PG

SB2

Crude oil outlet

6in-F-10006-HB2D-PG

SB3

Heating Medium inlet


SB4

Heating Medium outlet


BF5

10-PSV-0153

2in-V-10012-HA6A

BF6

44-PSV-2013

3in-V-44025-HA1C

DATE FITTED

SIG

DATE PULLED

SIG



Page 64 / 105


Isolation/Reinstatement Procedures 6.05 MP Separator V-1002





The boundary isolations for the oil processing facilities are in place, and the MP separator has been flushed, drained and nitrogen purged, as described in Section 6.01 of this volume






Prior to vessel entry, the MP separator requires to be physically disconnected from the associated pipework by either the rotation of spectacle blinds or the removal of maintenance spools within the process side blinded with correctly rated blind flanges



It is assumed that the pressure safety relief valves for the MP separator will be removed for certification. The flare side flanges for the relief valves must be isolated by suitably rated blind flanges










Page 65 / 105




(1)

REMOVE the blanks then carefully OPEN the vent valves for the level gauges fitted to the vessel. This will ENSURE that there is no pressure trapped in the MP separator.

Note: Any remaining gases in the MP separator must be vented to a safe area suitable for the disposal of hydrocarbon gases. (2)


(3)


(4)


(5)


(6)

DIVIDE the Belly Drain line at Nozzle N6 and SWING Spectacled Blind SB6 to the CLOSED position.

(7)


(8)


(9)


(10)


(11)


(12)

DIVIDE the Belly Drain line at Nozzle N11A and SWING Spectacled Blind SB11A to the CLOSED position.

(13)

DIVIDE the Belly Drain line at Nozzle N11B and SWING Spectacled Blind SB11B to the CLOSED position.

(14)

DIVIDE the Belly Drain line at Nozzle N11C and SWING Spectacled Blind SB11C to the CLOSED position.


Page 66 / 105




(15)

DIVIDE the Belly Drain line at Nozzle N11D and SWING Spectacled Blind SB11D to the CLOSED position.

(16)

DIVIDE the Belly Drain line at Nozzle N11E and SWING Spectacled Blind SB11E to the CLOSED position.

(17)

DIVIDE the Blowdown line at Nozzle N7 and INSERT Spade S7 to the flange faces.

(18)


(19)


(20)


(21)


(22)


Note: Ensure that the open-ended pipework on the relief line from the MP separator are blanked off once the pressure safety relief valves are removed. (23)

The MP separator is available for entry when the appropriate Vessel Entry Permit has been issued.


Page 67 / 105





(2)


(3)


(4)


(5)


(6)


(7)


(8)

DIVIDE the Belly Drain line at Nozzle N6 and SWING Spectacled Blind SB6 to the OPEN position then MAKE UP the flange faces.

(9)


(10)


(11)


(12)


(13)


(14)

DIVIDE the Belly Drain line at Nozzle N11A and SWING Spectacled Blind SB11A to the OPEN position then MAKE UP the flange faces.

(15)

DIVIDE the Belly Drain line at Nozzle N11B and SWING Spectacled Blind SB11B to the OPEN position then MAKE UP the flange faces. ID: M-CPH-1171-01417_EN_Section_6.doc Page 68 / 105



6.05.3 Reinstatement Procedure (Continued)

(16)

DIVIDE the Belly Drain line at Nozzle N11C and SWING Spectacled Blind SB11C to the OPEN position then MAKE UP the flange faces.

(17)

DIVIDE the Belly Drain line at Nozzle N11D and SWING Spectacled Blind SB11D to the OPEN position then MAKE UP the flange faces.

(18)

DIVIDE the Belly Drain line at Nozzle N11E and SWING Spectacled Blind SB11E to the OPEN position then MAKE UP the flange faces.

(19)

DIVIDE the Blowdown line at Nozzle N7 and REMOVE Spade S7 then MAKE UP the flange faces.

(20)


(21)


The MP separator, V-1002 has now been reinstated. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary.


Page 69 / 105



LOCATION

LINE No

SB1

Nozzle N1

14in-F-10008-HA2D-PG

SB2

Nozzle N2

10in-G-10004-HA2D-PG

SB3

Nozzle N3

8in-F-10009-HA2D-PG

SB4

Nozzle N4


SB6

Nozzle N6

2in-D-10023-HA1C

S7

Blowdown Line

4in-V-10015-HA2D

S8

Nozzle N8

6in-V-10013-HA2D

S10A

Nozzle N10A

1in-WW-10003-HA2D

S10B

Nozzle N10B

1in-WW-10003-HA2D

S10C

Nozzle N10C

1in-WW-10003-HA2D

S10D

Nozzle N10D

1in-WW-10003-HA2D

S10E

Nozzle N10E

1in-WW-10003-HA2D

DATE FITTED

SIG

DATE PULLED

SIG



Page 70 / 105


Isolation/Reinstatement Procedures 6.05.4 Spading Checklist V-1002 (Continued) BLIND No

LOCATION

LINE No

SB11A

Nozzle N11A

2in-D-10018-HA1C

SB11B

Nozzle N11B

2in-D-10019-HA1C

SB11C

Nozzle N11C

2in-D-10020-HA1C

SB11D

Nozzle N11D

2in-D-10021-HA1C

SB11E

Nozzle N11E

2in-D-10022-HA1C

BF12

10-PSV-0203A

8in-V-10014-HA1C

BF13

10-PSV-0203B

8in-V-10014-HA1C

DATE FITTED

SIG

DATE PULLED

SIG



Page 71 / 105



6.06 MP Crude Oil Heater E-1002





The boundary isolations for the oil processing facilities are in place, and the MP crude oil heater has been flushed and drained, as described in Section 6.01 of this volume






This procedure is written with the viewpoint that the MP crude oil heater has been shut down as part of the overall oil processing facilities shutdown. The MP crude oil heater is normally in constant use to heat the partially stabilised crude oil from the MP separator passing to the LP separator for full stabilisation






It is assumed that the Pressure Safety Relief Valve 10-PSV-0253 for the crude inlet to the MP crude oil heater will be removed for certification. The flare side flange on the relief line must be isolated by a suitably rated blind flange





Page 72 / 105




(1)

Carefully OPEN the drain valve for the crude inlet to the MP crude oil heater. This will ENSURE that there is no pressure trapped in the cold side of the heater.

Note: Any remaining drainings from the cold side of the heater must be directed to the skid drip pan which is suitable for the disposal of liquid hydrocarbons. (2)


(3)


(4)

Carefully OPEN the drain valve for the heating medium outlet from the MP crude oil heater. This will ENSURE that there is no pressure trapped in the warm side of the heater.

Note: Any remaining drainings from the warm side of the heater must be directed to the skid drip pan which is suitable for the disposal of heating medium. (5)

SWING Spectacled Blind SB3 on the heating medium inlet to the CLOSED position.

(6)

SWING Spectacled Blind SB4 on the heating medium outlet to the CLOSED position.

(7)

If the Pressure Safety Relief Valve 10-PSV-0253 for the crude inlet is to be removed for recertification, the flare pipework must be blinded off using Blind Flange BF5 and included on Spading Checklist E-1002.

Note: Ensure that the open-ended pipework on the crude inlet and heating medium outlet from the MP crude oil heater are blanked off once the pressure safety relief valves are removed.


Page 73 / 105






(2)


(3)


(4)

SWING Spectacled Blind SB3 on the heating medium inlet to the OPEN position.

(5)

SWING Spectacled Blind SB4 on the heating medium outlet to the OPEN position.

(6)


(7)

ENSURE that the drain valves for the crude inlet and heating medium outlet lines are CLOSED.

The MP Crude Oil Heater, E-1002 has now been reinstated. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary.


Page 74 / 105



LOCATION

LINE No

SB1

Crude oil inlet

16in-F-10009-HA2D-PG

SB2

Crude oil outlet

20in-F-10010-HA2D

SB3

Heating Medium inlet


SB4

Heating Medium outlet


BF5

10-PSV-0253

3in-V-10018-HA1C

DATE FITTED

SIG

DATE PULLED

SIG




Page 75 / 105



6.07 LP Separator V-1003





The boundary isolations for the oil processing facilities are in place, and the LP separator has been flushed, drained and nitrogen purged, as described in Section 6.01 of this volume






Prior to vessel entry, the LP separator requires to be physically disconnected from the associated pipework by either the rotation of spectacle blinds or the removal of maintenance spools within the process side blinded with correctly rated blind flanges



It is assumed that the pressure safety relief valves for the LP separator will be removed for certification. The flare side flanges for the relief valves must be isolated by suitably rated blind flanges










Page 76 / 105




(1)

REMOVE the blanks then carefully OPEN the vent valves for the level gauges fitted to the vessel. This will ENSURE that there is no pressure trapped in the LP separator.

Note: Any remaining gases in the LP separator must be vented to a safe area suitable for the disposal of hydrocarbon gases. (2)


(3)


(4)


(5)


(6)

DIVIDE the minimum flowline for the crude oil transfer pumps at Nozzle N5 and INSERT Spade S5 to the flange faces.

(7)

LEAVE Spectacle Blind SB6 on the crude oil outlet drain line in the CLOSED position.

(8)


(9)


(10)


(11)


(12)


(13)

DIVIDE the Belly Drain line at Nozzle N11A and SWING Spectacled Blind SB11A to the CLOSED position.

(14)

DIVIDE the Belly Drain line at Nozzle N11B and SWING Spectacled Blind SB11B to the CLOSED position.


Page 77 / 105




(15)

DIVIDE the Belly Drain line at Nozzle N11C and SWING Spectacled Blind SB11C to the CLOSED position.

(16)

DIVIDE the Belly Drain line at Nozzle N11D and SWING Spectacled Blind SB11D to the CLOSED position.

(17)

DIVIDE the Belly Drain line at Nozzle N11E and SWING Spectacled Blind SB11E to the CLOSED position.

(18)

DIVIDE the Blowdown line at Nozzle N7 and INSERT Spade S7 to the flange faces.

(19)


(20)


(21)

POSITION an air mover within each vessel access hatch ENSURING that the exhaust ducting vents are led away to a safe area.

(22)


(23)


Note: Ensure that the open-ended pipework on the relief line from the LP separator are blanked off once the pressure safety relief valves are removed. (24)

The LP separator is available for entry when the appropriate Vessel Entry Permit has been issued.


Page 78 / 105





(2)


(3)


(4)


(5)


(6)


(7)


(8)

DIVIDE the minimum flowline for the crude oil transfer pump at Nozzle N5 and REMOVE Spade S5 then MAKE UP the flange faces.

(9)

LEAVE Spectacled Blind SB6 on the crude oil outlet drain line in the CLOSED position.

(10)


(11)


(12)


(13)


(14)


(15)

DIVIDE the Belly Drain line at Nozzle N11A and SWING Spectacled Blind SB11A to the OPEN position then MAKE UP the flange faces.


Page 79 / 105


Isolation/Reinstatement Procedures 6.07.3 Reinstatement Procedure (Continued)

(16)

DIVIDE the Belly Drain line at Nozzle N11B and SWING Spectacled Blind SB11B to the OPEN position then MAKE UP the flange faces.

(17)

DIVIDE the Belly Drain line at Nozzle N11C and SWING Spectacled Blind SB11C to the OPEN position then MAKE UP the flange faces.

(18)

DIVIDE the Belly Drain line at Nozzle N11D and SWING Spectacled Blind SB11D to the OPEN position then MAKE UP the flange faces.

(19)

DIVIDE the Belly Drain line at Nozzle N11E and SWING Spectacled Blind SB11E to the OPEN position then MAKE UP the flange faces.

(20)

DIVIDE the Blowdown line at Nozzle N7 and REMOVE Spade S7 then MAKE UP the flange faces.

(21)


(22)


The LP separator, V-1003 has now been reinstated. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary.


Page 80 / 105



LOCATION

LINE No

SB1

Nozzle N1

20in-F-10010-HA2D

SB2

Nozzle N2

16in-G-10006-HA2D

SB3

Nozzle N3

12in-F-10011-HA2D

SB4

Nozzle N4


S5

Nozzle N5

4in-F-10013-HA2D

SB6

Nozzle N6

2in-D-10033-HA1C

S7

Blowdown Line

4in-V-10021-HA2D

S8

Nozzle N8

4in-V-10019-HA2D

S10A

Nozzle N10A

1in-WW-10004-HA2D

S10B

Nozzle N10B

1in-WW-10004-HA2D

S10C

Nozzle N10C

1in-WW-10004-HA2D

S10D

Nozzle N10D

1in-WW-10004-HA2D

S10E

Nozzle N10E

1in-WW-10004-HA2D

DATE FITTED

SIG

DATE PULLED

SIG




Page 81 / 105


Isolation/Reinstatement Procedures 6.07.4 Spading Checklist V-1003 (Continued) BLIND No

LOCATION

LINE No

SB11A

Nozzle N11A

2in-D-10028-HA1C

SB11B

Nozzle N11B

2in-D-10029-HA1C

SB11C

Nozzle N11C

2in-D-10030-HA1C

SB11D

Nozzle N11D

2in-D-10031-HA1C

SB11E

Nozzle N11E

2in-D-10032-HA1C

BF12

13-PSV-0303A

6in-V-10020-HA1C

BF13

13-PSV-0303B

6in-V-10020-HA1C

DATE FITTED

SIG

DATE PULLED

SIG



Page 82 / 105



6.08 Produced Water Transfer Pumps P-1002A/B

WARNING:

THIS PROCEDURE MUST BE READ AND FULLY UNDERSTOOD BEFORE ATTEMPTING TO CARRY OUT ANY ACTION.




The boundary isolations for the oil processing facilities are in place, and the produced water transfer pumps have been water flushed, as described in Section 6.01 of this volume






This procedure is written with the viewpoint that the produced water transfer pumps have been shut down as part of the overall oil processing facilities shutdown. However, the produced water transfer pumps are rated for 100% duty and normally operate on a Duty/Standby basis. As such, any one pump can be shut down for maintenance leaving the other pump on-line. In the stand-alone maintenance isolation situation the off-line pump will require to be valve isolated, depressurised and drained, followed by being isolated by spading before intrusive maintenance can commence. The following procedure describes the isolation for either standalone or boundary isolation situations on the understanding that in the stand-alone situation the off-line pump still has to be depressurised and drained and the alternative pump is operating normally



This procedure should be used in conjunction with the Boundary Isolation Valve Checklist and Spading Checklists, P-1002A and B in the case of maintenance within the boundary



This procedure should be used in conjunction with the Valve Isolation Checklists, P-1002A and B and Spading Checklists P-002A and B in the case of stand-alone maintenance during normal operations

Note: In the stand-alone isolation procedure, ENSURE that the pump is electrically isolated with the Electrical Isolation Certificate issued before any mechanical isolation of the pump is started. 

The Spade Schedules and Valve Isolation Checklists should be used in conjunction with the marked up P&ID CUR-MAS-PM20045-501 included at the end of the procedure


Page 83 / 105




This procedure is written for Produced Water Transfer Pump P-1002A. The same procedure can be used for identical Pump P-1002B utilising the valve tag numbers included in the Valve Isolation Checklist. Note: Steps 1 to 4 describe the necessary valve isolations for a standalone maintenance isolation. Steps 5 to 6 describe the turning of the various spectacle blinds and removal of maintenance spools as required in either case (Boundary or Stand-alone Isolation). (1)

CLOSE, LOCK and TAG the 3in Isolation Ball Valve for the pump suction line.

(2)

CLOSE, LOCK and TAG the 2in Isolation Ball Valve for the pump discharge line.

(3)

OPEN the ¾in Drain Valve for the pump suction line to SLOWLY DEPRESSURISE and DRAIN the pipework and pump casing. ENSURE that all drainings are directed to the Hazardous Area Open Drains for safe disposal and CLOSE the drain valve on completion.

(4)

ENSURE that there is no pressure trapped in the pump body by ISOLATING Pressure Gauge 10-PG-0326 for the pump discharge, REMOVING the instrument and CAREFULLY RE-OPENING the isolation valve. REPLACE the pressure gauge once the pump is confirmed as fully depressurised.

(5)

REMOVE the pump suction maintenance spool and Y-type strainer for cleaning then INSTALL Blind Flange BF1 to the upstream pipe flange.

Note: Ensure that the suction line is blanked off at the pump once the maintenance spool is removed. (6)

REMOVE the pump discharge maintenance spool and nonreturn valve then INSTALL Blind Flange BF2 to the downstream pipe flange.

Note: Ensure that the discharge line is blanked off at the pump once the maintenance spool is removed.


Page 84 / 105





RECONFIRM the boundary isolations on the Boundary Isolation Checklist before removing any blind flanges or spades (in the case of a boundary isolated maintenance activity).

(2)

REMOVE Blind Flange BF1 and REFIT the pump suction maintenance spool. Ensure that the inlet strainer is replaced and the blank is removed from the pump suction line.

(3)

REMOVE Blind Flange BF2 and REFIT the pump discharge maintenance spool. Ensure that the non-return valve is replaced and the blank is removed from the pump discharge line.

In the case of the boundary isolated maintenance activity, this completes the reinstatement of the pump. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary. In the case of the stand-alone isolation of the pump, the following valves require to be opened to return the pump to service: (4)

REMOVE the TAG, UNLOCK and OPEN the 3in Isolation Valve for the pump suction line.

(5)

REMOVE the TAG, UNLOCK and OPEN the 2in Isolation Valve for the pump discharge line.

(6)

PARTIALLY OPEN the ¾in Drain Valve to prime the pump. CLOSE the drain valve as soon as the pump is primed.

The produced water transfer pump has now been reinstated following stand-alone isolation and can be returned to service once the Electrical Isolation Certificate and Work Permit have been signed off.


Page 85 / 105



6.08.4 Valve Isolation Checklist P-1002A (Stand-alone) VALVE TAG No

LOCATION

LINE No

ISOLATED POSITION

HV-10174

Pump suction line

3in-WP-10004-HA1E-HC25

CLOSED

HV-10176

Pump discharge line


CLOSED

SIG/ DATE

COMMENTS NOTE:



Page 86 / 105



6.08.5 Valve Isolation Checklist P-1002B (Stand-alone) VALVE TAG No

LOCATION

LINE No

ISOLATED POSITION

HV-10171

Pump suction line


CLOSED

HV-10173

Pump discharge line


CLOSED

SIG/ DATE

COMMENTS NOTE:


Page 87 / 105


Isolation/Reinstatement Procedures 6.08.6 Spading Checklist P-1002A BLIND No

LOCATION

LINE No

BF1

Pump suction line


BF2

Pump discharge line


DATE FITTED

SIG

DATE PULLED

SIG




Page 88 / 105


Isolation/Reinstatement Procedures 6.08.7 Spading Checklist P-1002B BLIND No

LOCATION

LINE No

BF1

Pump suction line


BF2

Pump discharge line


DATE FITTED

SIG

DATE PULLED

SIG




Page 89 / 105



6.09 Crude Oil Transfer Pumps P-1001A/B

WARNING:





The boundary isolations for the oil processing facilities are in place, and the crude oil transfer pumps have been water flushed, as described in Section 6.01 of this volume






This procedure is written with the viewpoint that the crude oil transfer pumps have been shutdown as part of the overall oil processing facilities shutdown. However, the crude oil transfer pumps are rated for 100% duty and normally operate on a Duty/Standby basis. As such, any one pump can be shut down for maintenance leaving the other pump on-line

In the stand-alone maintenance isolation situation the off-line pump will require to be valve isolated, depressurised and drained, followed by being isolated by spading before intrusive maintenance can commence The following procedure describes the isolation for either stand-alone or boundary isolation situations on the understanding that in the stand-alone situation the off-line pump still has to be depressurised and drained and the alternative pump is operating normally 

This procedure should be used in conjunction with the Boundary Isolation Valve Checklist and Spading Checklists, P-1001A and B in the case of maintenance within the boundary



This procedure should be used in conjunction with the Valve Isolation Checklists, P-1001A and B and Spading Checklists P-1001A and B in the case of stand-alone maintenance during normal operations

Note: In the stand-alone isolation procedure ENSURE that the pump is electrically isolated with the Electrical Isolation Certificate issued before any mechanical isolation of the pump is started. 

The Spade Schedules and Valve Isolation Checklists should be used in conjunction with the marked up P&ID CUR-MAS-PM20045-501 included at the end of the procedure


Page 90 / 105




This procedure is written for Crude Oil Transfer Pump P-1001A. The same procedure can be used for identical pump P-1001B utilising the valve tag numbers included in the Valve Isolation Checklist. Note: Steps 1 to 5 describe the necessary valve isolations for a standalone maintenance isolation. Steps 6 to 7 describe the turning of the various spectacle blinds and removal of maintenance spools as required in either case (Boundary or Stand-alone Isolation). (1)

CLOSE, LOCK and TAG the 12in Isolation Ball Valve for the pump suction line.

(2)

CLOSE, LOCK and TAG the 8in Isolation Ball Valve for the pump discharge line.

(3)

OPEN the ¾in Drain Valve for the pump suction line to SLOWLY DEPRESSURISE and DRAIN the pipework and pump casing. ENSURE that all drainings are directed to the Hazardous Area Open Drains for safe disposal and CLOSE the drain valve on completion.

(4)

OPEN the ¾in Drain Valve for the pump discharge line to SLOWLY DEPRESSURISE and DRAIN the discharge pipework. ENSURE that all drainings are directed to the Hazardous Area Open Drains for safe disposal and CLOSE the drain valve on completion.

(5)

ENSURE that there is no pressure trapped in the pump body by ISOLATING Pressure Gauge 10-PG-0322 for the pump discharge, REMOVING the instrument and CAREFULLY RE-OPENING the isolation valve. REPLACE the pressure gauge once the pump is confirmed as fully depressurised.

(6)

REMOVE the pump suction maintenance spool and Y-type strainer for cleaning then INSTALL Blind Flange BF1 to the upstream pipe flange.

Note: Ensure that the suction line is blanked off at the pump once the maintenance spool is removed. (7)

REMOVE the pump discharge maintenance spool and nonreturn valve then INSTALL Blind Flange BF2 to the downstream pipe flange.

Note: Ensure that the discharge line is blanked off at the pump once the maintenance spool is removed.


Page 91 / 105





RECONFIRM the boundary isolations on the Boundary Isolation Checklist before removing any blind flanges or spades (in the case of a boundary isolated maintenance activity).

(2)

REMOVE Blind Flange BF1 and REFIT the pump suction maintenance spool. Ensure that the inlet strainer is replaced and the blank is removed from the pump suction line.

(3)

REMOVE Blind Flange BF2 and REFIT the pump discharge maintenance spool. Ensure that the non-return valve is replaced and the blank is removed from the pump discharge line.

In the case of the boundary isolated maintenance activity, this completes the reinstatement of the pump. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary. In the case of the stand-alone isolation of the pump, the following valves require to be opened to return the pump to service. (4)

REMOVE the TAG, UNLOCK and OPEN the 12in Isolation Valve for the pump suction line.

(5)

REMOVE the TAG, UNLOCK and OPEN the 8in Isolation Valve for the pump discharge line.

(6)

PARTIALLY OPEN the ¾in Drain Valve on the pump suction line to prime the pump. CLOSE the drain valve as soon as the pump is primed.

The crude oil transfer pump has now been reinstated following standalone isolation and can be returned to service once the Electrical Isolation Certificate and Work Permit have been signed off.


Page 92 / 105



6.09.4 Valve Isolation Checklist P-1001A (Stand-alone) VALVE TAG No

LOCATION

LINE No

ISOLATED POSITION

HV-10162

Pump suction line

12in-F-10011-HA2D

CLOSED

HV-10168

Pump discharge line

8in-F-10012-HA2D

CLOSED

SIG/ DATE

COMMENTS NOTE:


Page 93 / 105



6.09.5 Valve Isolation Checklist P-1001B (Stand-alone) VALVE TAG No

LOCATION

LINE No

ISOLATED POSITION

HV-10165

Pump suction line

12in-F-10011-HA2D

CLOSED

HV-10169

Pump discharge line

8in-F-10012-HA2D

CLOSED

SIG/ DATE

COMMENTS NOTE:



Page 94 / 105


Isolation/Reinstatement Procedures 6.09.6 Spading Checklist P-1001A BLIND No

LOCATION

LINE No

BF1

Pump suction line

12in-F-10011-HA2D

BF2

Pump discharge line

8in-F-10012-HA2D

DATE FITTED

SIG

DATE PULLED

SIG




Page 95 / 105


Isolation/Reinstatement Procedures 6.09.7 Spading Checklist P-1001B BLIND No

LOCATION

LINE No

BF1

Pump suction line

12in-F-10011-HA2D

BF2

Pump discharge line

8in-F-10012-HA2D

DATE FITTED

SIG

DATE PULLED

SIG




Page 96 / 105



6.10 Electrostatic Coalescer V-1004

WARNING:




The boundary isolations for the oil processing facilities are in place, and the electrostatic coalescer has been flushed, drained and nitrogen purged, as described in Section 6.01 of this volume






Prior to vessel entry the electrostatic coalescer requires to be physically disconnected from the associated pipework by either the rotation of spectacle blinds or the removal of maintenance spools within the process side blinded with correctly rated blind flanges



It is assumed that the coalescer pressure safety relief valve will be removed for certification. The flare side flanges must be isolated by suitably rated blind flanges



Prior to vessel entry the hydrocarbon and nitrogen gases must be displaced until the atmosphere within the vessel contains 21% oxygen and less than 0.25% (volume) hydrocarbons

WARNING:


ANY VENTING OF NITROGEN TO ATMOSPHERE SHOULD BE TREATED WITHIN EXTREME CARE, AS IN HIGH CONCENTRATIONS, INHALATION WILL CAUSE UNCONSCIOUSNESS ALMOST IMMEDIATELY. THEREFORE, NO LOCAL CONTINUOUS VENTING OF EQUIPMENT SHOULD TAKE PLACE UNLESS IT IS PIPED TO A SUITABLE LOCATION WHERE PERSONNEL ARE NOT EXPOSED.






This procedure should be used in conjunction with Spading Checklist, V-1004 and marked up P&ID CUR-MAS-PM-20046-501 included at the end of this procedure


Page 97 / 105


Isolation/Reinstatement Procedures 6.10.2 Preparation for Vessel Entry Procedure

(1)

REMOVE the blank then carefully OPEN the vent valve for the Level Gauge Glass 10-LG-0414. This will ENSURE that there is no pressure trapped in the coalescer.

Note: Any remaining gases in the coalescer must be vented to a safe area suitable for the disposal of hydrocarbon gases. (2)

SWING Spectacled Blind SB1 on the oil inlet to the CLOSED position.

(3)

SWING Spectacled Blind SB2 on the dry oil outlet line from the coalescer to the CLOSED position.

(4)

DIVIDE the separated water outlet line at Nozzle N3 and INSERT Spade S3 to the flange faces.

(5)

DIVIDE the Sample line at Nozzle N6A and INSERT Spade S6A to the flange faces.

(6)

DIVIDE the Sample line at Nozzle N6B and INSERT Spade S6B to the flange faces.

(7)

DIVIDE the Sample line at Nozzle N6C and INSERT Spade S6C to the flange faces.

(8)

DIVIDE the Sample line at Nozzle N6D and INSERT Spade S6D to the flange faces.

(9)

DIVIDE the Sample line at Nozzle N6E and INSERT Spade S6E to the flange faces.

(10)

SWING Spectacled Blinds SB7A-E at Nozzles N7A-E respectively on the belly drain lines to the CLOSED position.

(11)


(12)

OPEN the Vessel Manway Doors M1A and M1B.

(13)

POSITION an air mover within each manway door ENSURING the exhaust ducting vents are led away to a safe area.

(14)

Use the air mover to displace the gases within the coalescer until the atmosphere inside the vessel contains 21% oxygen and less than 0.25% hydrocarbons.

(15)

If the Coalescer Relief Valves 10-PSV-0403A and B are to be removed for recertification, the flare pipework must be blinded off using Blind Flanges BF9 and BF10 and included on Spading Checklist V-1004.

(16)

The electrostatic coalescer is available for entry when the appropriate Vessel Entry Permit has been issued.


Page 98 / 105


Isolation/Reinstatement Procedures 6.10.3 Reinstatement Procedure


(2)

CONFIRM that all equipment has been removed from the vessel and the internal rods are in place and secure. CLOSE the Manway Doors M1A and M1B.

(3)


(4)

SWING Spectacled Blind SB1 on the oil inlet line to the OPEN position.

(5)

SWING Spectacled Blind SB2 on the dry oil outlet line to the OPEN position.

(6)

DIVIDE the produced water outlet line at Nozzle N3 and REMOVE Spade S3 then MAKE UP the flange faces.

(7)

DIVIDE the Sample line at Nozzle N6A and REMOVE Spade S6A then MAKE UP the flange faces.

(8)

DIVIDE the Sample line at Nozzle N6B and REMOVE Spade S6B then MAKE UP the flange faces.

(9)

DIVIDE the Sample line at Nozzle N6C and REMOVE Spade S6C then MAKE UP the flange faces.

(10)

DIVIDE the Sample line at Nozzle N6D and REMOVE Spade S6D then MAKE UP the flange faces.

(11)

DIVIDE the Sample line at Nozzle N6E and REMOVE Spade S6E then MAKE UP the flange faces.

(12)

SWING Spectacle Blinds SB7A-E at Nozzles N7A-E respectively on the belly drain lines to the OPEN position.

(13)

DIVIDE the Relief Line at Nozzle N8 and REMOVE Spade S8 then MAKE UP the flange faces.

(14)

If the coalescer Relief Valves 10-PSV-0403A and B have been removed for recertification, REMOVE Blind Flanges BF9 and BF10 on the flare side pipe flange and REFIT the relief valves.

The electrostatic coalescer has now been reinstated. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary. ID: M-CPH-1171-01417_EN_Section_6.doc

Page 99 / 105



LOCATION

LINE No

SB1

Nozzle N1

8in-F-10012-HA2D

SB2

Nozzle N2

8in-F-10014-HA2D

S3

Nozzle N3


S6A

Nozzle N6A

½in-D-10048-HA2D-HC25

S6B

Nozzle N6B

½in-D-10047-HA2D-HC25

S6C

Nozzle N6C

½in-D-10046-HA2D-HC25

S6D

Nozzle N6D

½in-D-10045-HA2D-HC25

S6E

Nozzle N6E

½in-D-10044-HA2D-HC25

SB7A

Belly Drain Line

2in-D-10037-HA1C

SB7B

Belly Drain Line

2in-D-10055-HA1C

SB7C

Belly Drain Line

2in-D-10056-HA1C

SB7D

Belly Drain Line

2in-D-10057-HA1C

SB7E

Belly Drain Line

2in-D-10058-HA1C

Relief Line

4in-V-10025-HA2D

BF9

10-PSV-0403A

4in-V-10024-HA1C

BF10

10-PSV-0403B

4in-V-10024-HA1C

S8

DATE FITTED

SIG

DATE PULLED

SIG

COMMENTS BF = Blind Flange SB = Spectacled Blind S = Spade OPERATOR SIGNATURE: DATE:


Page 100 / 105



6.11 Export Crude Oil Cooler E-1004

WARNING:




The boundary isolations for the oil processing facilities are in place, and the export crude oil cooler has been flushed and drained, as described in Section 6.01 of this volume






This procedure is written with the viewpoint that the export crude oil cooler has been shut down as part of the overall oil processing facilities shutdown. The export crude oil heater is in continuous use to regulate the temperature of the dehydrated crude oil from the electrostatic coalescer passing to the cargo oil tanks at 30oC









Page 101 / 105




(1)

Carefully OPEN the vent valve for the crude inlet to the export crude oil cooler. This will ENSURE that there is no pressure trapped in the warm side of the cooler.

(2)

Carefully OPEN the drain valve for the crude outlet from the export crude oil cooler. This will ENSURE that there are no liquids trapped in the warm side of the cooler.

Note: Any remaining drainings from the warm side of the cooler must be directed to the skid drip pan which is suitable for the disposal of liquid hydrocarbons. (3)


(4)


(5)

Carefully OPEN the vent valve for the cooling medium outlet from the export crude oil cooler. This will ENSURE that there is no pressure trapped in the cold side of the cooler.

Note: Any remaining drainings from the cold side of the cooler must be directed to the skid drip pan which is suitable for the disposal of cooling medium. (6)

SWING Spectacled Blind SB3 on the cooling medium inlet to the CLOSED position.

(7)

SWING Spectacled Blind SB4 on the cooling medium outlet to the CLOSED position.


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(2)


(3)


(4)

SWING Spectacled Blind SB3 on the cooling medium inlet to the OPEN position.

(5)

SWING Spectacled Blind SB4 on the cooling medium outlet to the OPEN position.

(6)

ENSURE that the drain valves for the cooling medium inlet and crude outlet lines are CLOSED.

(7)

ENSURE that the vent valves for the crude inlet and cooling medium outlet lines are CLOSED.

The Export Crude Oil Heater E-1004 has now been reinstated. The oil processing facilities boundary isolations are still in place and should not be removed until all maintenance work is complete within the boundary.


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LOCATION

LINE No

SB1

Crude oil inlet

8in-F-10014-HA2D

SB2

Crude oil outlet

8in-F-10015-HA2D

SB3

Cooling Medium inlet

6in-CM-45001-HA1C

SB4

Cooling Medium outlet

6in-HM-45002-HA1C

DATE FITTED

SIG

DATE PULLED

SIG




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6.12 Oil Processing Facilities Boundary Reinstatement

WARNING:


6.12.1 Introduction

The oil processing facilities have been shutdown, drained and depressurised in preparation for major maintenance activities as described in the planned shutdown procedure included in Section 6.01 of this book. The oil processing facilities were boundary isolated, flushed with utility seawater and purged with nitrogen, as described in Section 6.01 of this book. The equipment within the oil processing facilities has undergone intrusive maintenance activities which required physical isolation by spading/blinding, air displacement of the nitrogen before vessel entry, followed by a despading reinstatement activity of each facility within the boundary isolation as described in Sections 6.02 to 6.11. With all maintenance activity complete, the Boundary Isolation can be reinstated as follows:

6.12.2 Boundary Reinstatement

Following the completion of all maintenance/inspection workscopes, the crude oil processing facilities require to be pre-start pressure tested utilising a nitrogen/helium trace gas to prove system containment integrity. This operation is undertaken by specialist contract personnel. The boundary reinstatement of the oil processing facilities takes place only after the pre-start pressure tests above have been successfully completed and witnessed by operations supervision. The cold start-up procedure in Section 5.01 of this volume details the removal of the boundary by use of the Cold Start-up Valve Checklist. Reference must now be made to Section 5 of this manual for these operating procedures.


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Oil Processing Facilities

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