Mu t p ase F ow an Flow Assurance Ol a User’s Meetin
Sam Kashou ETC Flow Assurance, MCP Team Team
Safety Moment Ensure safety devices are in place and functioning.
2
Safety Moment Ensure safety devices are in place and functioning.
2
Objective
To give a high level overview of Flow Assurance in Multiphase Flow
fluid faces while flowing inside we ores, pipe ines, an risers, etc.
have.
3
What i s Flow Assurance The
ability to produce and transport
in an economically and technically . Designing
and operating the production and transportation systems to manage challenges to the flow throughout the e e. Flow Assurance = Cash Flow Assurance 4
Identify
FA drivers that will influence concep se ec on
Identify
technology gaps & develop so u ons
Ensure
a
preferred concept is feasible from perspec ve
Ensure
preferred concept can be opera e sa e y an e ec ve y
5
What could happen if Flow Assurance Studies are not performed?
6
Hydrate Blockage and Remediation Offshore Pipeline (plug can be many meters long and in many sections of line)
Due to improper MEG dosage to prevent hydrates
7
Hydrate Blockage Offshore
8
Wax in Pipeline
9
Napthenates
10
Asphaltenes
11
Slugging
Test Separator Liquid Rates, Feb 7 1400
d / 1200 3 m , e 1000 t a d i u q i L r o t a r a p e S t e T
800
600
400
200
0 8500
8510
8520
8530
8540
8550
8560
Time, minutes
12
Explosion, Fire I t C o u l d be due to internal pipe corrosion
and lack of corrosion monitoring
13
Is this Flow Assurance? Overloaded Donkey (can’t move, therefore can’t flow - gravity dominated flow)
14
Flow Assurance Activities
HYDRAULIC MODELING
SOLIDS FORMATION
SYSTEM DESIGN PARAMETERS
STRATEGIES
SAMPLING
MULTIPHASE FLOW
HYDRATES
DIAMETERS
STARTUP & SHUTDOWN
WAX
ANA LYSES
BOUNDARIES
SLUGGING ASPHALTENES FLUID MODELING
THERMAL MODELING
SCALE
CHEMICAL INJECTION
TOPSIDES EQUIPMENT
INTERVENTION
15
The Flow Assurance Challenge
16
HOW ARE FLOW ASSURANCE STUDIES INTEGRATED
PHASE 1
PHASE 2
PHASE 3
PHASE 4
PHASE 5
IDENTIFY AND ASSESS OPPORTUNITY
GENERATE AND SELECT ALTERNATIVE(S)
DEVELOP PREFERRED ALTERNATIVE(S)
EXECUTE
OPERATE AND EVALUATE
17
HOW ARE FLOW ASSURANCE STUDIES INTEGRATED WITH THE PROJECT WORKSCOPE?
PHASE 1
PHASE 2
PHASE 3
PHASE 4
PHASE 5
ASSESS OPPORTUNITY
•
Fluid Sampling Program –
Reservoir Fluids
–
Water Samples
•
Plan Fluid Testing Program
•
Measure Key Fluid Properties –
PVT Data
–
Water Composition
–
H drate
–
Wax & Asphaltenes
–
Scale
18
HOW ARE FLOW ASSURANCE STUDIES INTEGRATED WITH THE PROJECT WORKSCOPE?
PHASE 1
PHASE 2
PHASE 3
PHASE 4
PHASE 5
SELECT ALTERNATIVE(S)
Flow Assurance Activities • • •
Perform any additional experimental testing e ne u
property pre ct ons
Steady state hydraulics of concepts of concepts
•
System deliverability
•
Preliminar FA Miti ation lan
•
Input to subsea facilities design work 19
HOW ARE FLOW ASSURANCE STUDIES INTEGRATED WITH THE PROJECT WORKSCOPE?
PHASE 1
PHASE 2
PHASE 3
PHASE 4
PHASE 5
PREFERRED ALTERNATIVE(S)
Flow Assurance Activities •
Continue experimental work if needed
•
p ate re nement o pre erre concept(s) using – Details of subsea facilities – – Refine transient simulations
•
Updates of FA Mitigation Strate
•
Development of Subsea Operating Philosophy 20
HOW ARE FLOW ASSURANCE STUDIES INTEGRATED WITH THE PROJECT WORKSCOPE?
PHASE 1
PHASE 2
PHASE 3
PHASE 4
PHASE 5
EXECUTE
Flow Assurance Activities •
Major flow assurance related tasks complete
•
Selection / compatibility of treating chemicals
•
Operating procedures
•
Start-up & commissioning
21
HOW ARE FLOW ASSURANCE STUDIES INTEGRATED WITH THE PROJECT WORKSCOPE?
PHASE 1
PHASE 2
PHASE 3
PHASE 4
PHASE 5 OPERATE AND EVALUATE
ow
ssurance
c v es
Provide support to operations as needed:
Modifications to chemical selection Program
Support of processing
z
Separation
z
Naphthenates
Blockage remediation issues
Optimize production 22
FLOW ASSURANCE Spectrum
u p ase Flow
Solids
Internal orros on
Reservoir Fluids
S stem Integration
Flow Assurance
Injection
Operability
Thermal Sand 23
FLOW ASSURANCE Spectrum (1) (1)
Reservoir Fluids ,
(2)
,
Multiphase Flow
z
Rheology, flow modeling
z
Pressure loss, diameter of tubing & flowlines ugg ng an
z
(3)
qu
surge
Solids
z
Hydrates, wax, asphaltenes, scale, naphthenates, etc.
z
Flow restrictions or blockages
(4)
Internal Corrosion 24
FLOW ASSURANCE Spectrum (2) (5)
Emulsions
(6)
Sand
z
Sand transport / deposition
z
Erosion
erma z
anagemen
Insulation, heating
25
FLOW ASSURANCE Spectrum (3) (8)
System Operability
z Various
operating modes: normal operation, shutdown, startup, well testing, turndown/rampup, pigging, etc.
(9)
Chemical Injection
(10)
System Integration
26
(1) RESERVOIR FLUIDS
Hydrocarbons z
z z z
Saturates / Paraffins / Alkanes Aromatics es ns
THERE CAN BE THOUSANDS OF DIFFERENT MOLECULES IN A RESERVOIR FLUID
Asphaltenes
z
Water
z
Mineral salts
z
CO2, H2S, mercaptans, N2, He
z
Metals
z
Microorgansims
THIS LEADS TO COMPLEX FLUID BEHAVIOR WHICH CAN BE DIFFICULT TO ANALYZE AND PREDICT 27
RESERVOIR FLUIDS Form
the Basis for Flow Assurance and other design work; F l o w A s s u r a n c e w o r k i s a s g o o d a s t h e R e s e r v o i r Fl u i d Sa m p l in g a n d A n a ly s is .
PVT Pressure, Vo ume, Temperature z
Describes the thermodynamic relationship between pressure, volume, and temperature for all phases
Phase Behavior z
Phase refers to the state of matter: gas, liquid, solid,
z
, relative quantities of each phase
Fluid Properties z
Parameters related to solids formation 28
RESERVOIR FLUIDS 350
PHASE ENVELOPE
Highest possible temperature and RESERVOIR pressure for which s nc qu or CRICONDENBAR gas phases can be observed
300 LIQUID 250
CRITICAL POINT
) a r a 200 b ( e r u s s r P
WELLHEAD FLOWLINE/ PIPELINE
CHOKE
CRICONDENTHERM
TWO PHASE REGION
100
50 DEW POINT CURVE
TOPSIDES SEPARATOR 0
50
100
150
200
VAPOR 250
300
350
400
450
500
Temperatur e (C) 29
RESERVOIR FLUIDS
Sampling F
Separator
Liquid Sampling Port
F
Downhole Sampling Tool
30
(2) MULTIPHASE FLOW
Multiphase flow is the simultaneous flow of multiple fluid phases (gas, oil, and water) inside a flow device.
The flow device can be: z
Reservoir
z
Wellbore
z
Flowlines
z
Risers
31
Quiz: What is a Pipeline? z A
i eline is a lon hole surrounded b
metal concentric with hole, z O.D.
of all pipes must exceed the I.D.
otherwise the hole will be on the outside, z All
pipe is to be hollow throughout
en re eng
Pipeline , as o , gas, blockage an wa er can
be added on site. 32
MULTIPHASE FLOW
Flow Regimes in Pipes ,
,
stability, slug catcher sizing, etc.
Dispersed Bubble Flow
Slug Flow
Annular Flow
Stratified Flo
33
Flow Regimes in Pipelines -
-
-
Various Flows
34
Flow Regimes in Pipelines, Severe Slugging
35
MULTIPHASE FLOW
Holdup (HL) . z
Due to slip HL > fraction of liquid due to phase behavior
Gas
~50% Liquid Holdup Liquid
36
MULTIPHASE FLOW
Holdup, this is very real Gas Condensate Liquid Holdup Example 60000 ) l b b ( p u d l o H d i u q i L l t o T
PIPESIM Plot Mar 17 2001
50000 Gas
40000 Li uid
30000 Gas
20000 Liquid
10000 0
Stock-tank Gas at Outlet (MMSCFD) PIPESIM for Windows © Baker Jardine & Associates, London
37
(3) SOLIDS
Hydrates
Scale
Asphaltenes
Calcium Naphthenates
38
HYDRATES “Ice
that burns”
39
HYDRATES
Water molecules
Methane “guest molecule”
40
HYDRATES 250
Subcooling Definition
200
Design Pressure
Subcooling or Temperature Depression
) a r 150 a b ( e r u s e100 r P
Hydrate Zone Design Temperature
Hydrate Free
0 0
5
10
15
20
25
30
Temperatu re (C) 41
HYDRATES
Hydrate prevention - Chemical Inhibitors
f
Methanol
f
yco s
z
,
,
,o
ers
Salt (brine)
Low dosage (a.k.a. LDHI) f
Anti-agglomerants (prevents accumulation)
f
Kinetic inhibitors (delay nucleation)
42
HYDRATES
Hydrate prevention above hydrate formation conditions) f
Insulation
f
Active heating
z z
Low pressure operation (maintain pressure below hydrate formation conditions)
43
WAX / PARAFFINS
Wide range of high molecular weight paraffins (alkanes or saturated hydrocarbons)
Slightly soluble in oil
Solidify from oil primarily due to a decrease in temperature
44
WAX / PARAFFINS As
wax solidifies from oil, there are
z
Wax deposition on tubing and pipe walls during normal flow
z
Gelling of the oil during shutdown
z
Increases in viscosity due to wax articles sus ended in the oil
45
WAX / PARAFFINS Wax
Management
z
Pigging
z
Chemical injection
z
Insulation
z z
c ve
ea ng
Operating procedures
46
Pigging
-
-
47
SCALE A
deposit of inorganic mineral compounds
48
SCALE
Scale formation and deposition occurs due to:
z
Mixing of different waters
z
Corrosion
Deposition can occur in t e: z
Formation
z
Wellbore
z
Flowlines
z
Process equipment 49
SCALE Scale
can be managed by:
z Prevent
deposition using chemical inhibitors
z Pre-treatment
to remove scale
z Allow
scale to form and periodically remove it
50
ASPHALTENES
What are Asphaltenes? , z
Defined by solubility
What is a Colloidal System? z
Dispersion of one phase in a continuous phase
z
Example: Milk fat in water
51
ASPHALTENES
Causes of Asphaltenes deposition
z
Asphaltenes can deposit z
Gas lifting
Formation, wellbore tubing, flowlines, and to sides
Asphaltenes can cause emulsion problems
Courtesy of Baker Petrol Petrol it
A s h al As altt ene deposition 52
ASPHALTENES
Asph phal alte tene nes s As z
– Co Cont ntro roll
Inhibitors
prevent asphaltene deposition orma y n ec e well
a
e
o om o
e
53
CALCIUM NAPHTHENATES
Naphthenates are a solid that forms from a reaction between calcium in produced water and naphthenic acid in oil
Found in some West African and North Sea fields
High TAN oils (TAN = total acid number)
54
(4) INTERNAL CORROSION
Corrosion can occur inside a pipe any time water is present
Corrosion is accelerated by the presence of O 2, CO2, or H2S (sour)
Pipeline failures are a big potential liability
Corrosion prevention z
Chemical inhibitors
z
Protective coatings, corrosion resistant alloys
z
Limit flow rates / velocities
z
Other 55
(5) EMULSIONS
Emulsions are complex mixtures of immiscible liquids consisting of a dispersed liquid in a continuous liquid phase
Water-in-oil emulsions z
Most common in crude oil systems
z
Exists in water cuts as hi h as 80%
Oil-in-water emulsions
Increased viscosity
Separation problems 56
EMULSIONS
Viscosity Albacore-Leste Oil -Brine Fluid
A3WCMU14
Fluid Temperature
Flow Velocity 2 ft/sec.
o
100 F
2500 o
110 F
P 2000 c , y t i s o s 1500 i V d i u l 1000 F
o
120 F
o
130 F
o
140 F 500
0 0
10
20
30
40
50
60
70
80
90
100
Water-Cut, % 57
(6) SAND Belongs on the beach…
58
SAND
Sand
Small quantities of sand are typically produced from oil and gas reservoirs
Sand can have detrimental impacts on production z
Erosion
z
Increase corrosion
z
Can form restrictions or plugging can se
e n ops es equ pmen
Sand transport be defined for sand transport
59
SAND Prediction and Monitoring
Prediction in design phase z z
Sand
ore ana ys s
we
es
a a
Erosion & solids transport modeling
Continuous or periodic monitoring for sand -
If a well begins to produce significant sand, then z z
Permanently shut-in
z
Operate at reduced flow rate
60
SAND Detection
Sand
Subsea
sand detectors are commercially available z Intrusive z Acoustic
61
SAND Detection
Sand
62
(7) THERMAL MANAGEMENT Why
are we interested in thermal mana ement? z
Many of the potential solids are hydrates and wax
z
significantly) with decreasing temperature
z
Insulation – keep the heat you have
z
Active heating – add energy 63
THERMAL MANAGEMENT
Insulation z
Flowlines
z
Subsea equipment
64
Pipeline Insulation Manufacturing
65
(8) OPERABILITY Development
of Operating Philosophies, Strate ies and eventuall Procedures
Integration
Definition Consider O
of Flow Assurance into system
of operating boundaries/ranges
various modes of operation
erational monitorin
Intervention
requirements
66
GENERAL OPERABILITY STRATEGIES For
Life Cycle
z Steady
State Operations (line sizes, pressure and temperature drops, flow rates, etc.)
(Production Start-up, Planned Shut, u - , , .
67
(9) CHEMICAL INJECTION
Chemicals are needed to control a number of potential solids and production chemistry concerns
Chemical compatibility
Chemical Injection – Design Philosophy
z
Chemical performance testing
z
Operation monitoring
68
CHEMICAL INJECTION Example Chemical Injection Layout STORAGE TANK FILTER
FLOW METER
FLOW CONTROL VALVE
PUMP
M
TUTA
FLYING LEADS
SUTA
UMBILICAL
SUBSEA TREE
69
(10) SYSTEM INTEGRATION Consider
z
Introduction
all components of production
Reservoir, wells, subsea equipment, ow nes, r sers, ops es process ng facilities, control and umbilical , .
Consider Address
interaction of all components
design interfaces
70
SYSTEM INTEGRATION
Emulsions / Foaming
Advanc ed MPF Modeling
Corrosion Control
Asphaltene Con trol Wax Contr ol MP Flow Improvement
Scale Cont rol
Hydrate Control Integrated Produc tio n Syst em Model
71
Systems World Wide Existing and to be Developed Field
Country
Length [km] 70 134 160 165
Diameter [in] 34 30-34 34 18
Depth [m] 200 1340 190 140
Subsea Development Yes Yes Both Yes
Production Start ? ? ? ?
Fluid
Gorgon Jansz Wheatstone WTR
Australia Australia Australia Australia
Ormen Lange atar Gas II Snøhvit Goldeneye Scarrab/Saffron South Pars 2+3
Norway ata Norway UK Egypt Iran
120 90 143 105 90 105
2x30 32 28 20 20 to 36 2x32
800-1100 50 250-345 120 90 65
Y es No Y es No Y es No
2007 2006 2005 2004 2003 2002
3 Phase 3 Phase 3 Phase 3 Phase 3 Phase 3 Phase
Canyon Express Firebird Huldra Gemini a e s an Sable Island Ras Gas
US US Norway US ana a Canada Qatar
92 10 145 44
2x12 dual 6 22 dual 12
2200 300 120 1050
2002 2001 2001 1999
175 92
<20 32
Y es yes No Y es o No No
3 Phase 3 Phase 3 phase 3 Phase ase 3 Phase 2 Phase
50
1999 1999
3 3 3 3
Phase Phase Phase Phase
72
Flow Issues in Pipelines, Can Cause Severe Headaches
Deepwater pipe section replacement Being at the wrong place and at the wrong time 73
Final Thoughts, Is this Flow Assurance?
Pipeline or a way Blockage?
74
Flow Assurance Modeling Example
75
Modeling: LNG Plant Start-up – Gas Flow Rate 100% gas flow is 22.5 BCM annual gas rate 80 )
D / 3
ramp up to 25% in 3 months
70
m M 60 M ( n a 50 l P G N 40 L t a e t 30 a R w o 20 l F s
hold at 12.5% for 1 month
Hold at 100%
hold at 25% for ramp up to 50% over 1 month
12.5% in 3 months
ramp up to 100% over 1 month
hold at 50% for 12 months
ramp up from 0 to . 3 months
G
Gas
0
0
60
120
180
240
300
360
420
480
540
600
660
720
780
84
Time (day s)
76
Modeling: LNG Plant Start-up – Pipeline Pressure 100% is 22.5 BCM annual gas rate
160 150 140 130 ) r 120 a 110 b ( e r 100 u s 90 s e r 80 P 70 e n i l e p i P
ramp up to 25% in 3 months
12.5% for 1 month
50 40 30 20 10 0
ramp up from 0 to 7.5% in mon s
0
60
Hold at 100%
hold at 25% for 1 month
Inlet
ramp up to 50% over 1 month
12.5% in 3 months
120
180
Outlet hold at 50% for 12 months
240
300
360
420
480
540
ramp up to 100% over 1 month
600
660
720
780
84
Time da s
77
Modeling: LNG Plant Start-up 100% gas fl ow is 22.5 BCM ann ual g as rate 26000 25% in 3 months
) 22000 3
hold at 25% for 1 month
m20000 ( e n 18000 i l e p 16000 i P n 14000 i
12.5% for 1 month
p 12000 u l 10000 o H 8000 d i u q 6000 i L
ramp up to 12.5% in 3 months ramp up from 0 to 7.5% in 3 months
4000 2000
60
ramp up to 50% over 1 month
Condensate
hold at 50% for 12 months
Hold at 100%
Water/MEG
0
0
ramp up to 100% over 1 month
120
180
240
300
360
420
480
540
600
660
720
780
840
Time (days)
78
Modeling: LNG Plant Start-up – Liquid Flow Rate 100% gas flow is 22.5 BCM annual g as rate 2500 ram u to 25% in 3 months
) 2250 D / 3
m 2000 ( t n a 1750 l
hold at 12.5% for 1 month
G 1500 N L t a 1250 e t a 1000 w o l F d i u q i
ram u to 100% over 1 month
ramp up to 50% over 1 month hold at 50% for 12 months
12.5% in 3 months
750 500
hold at 25% for 1 month
ramp up from 0 to . 3 months
Condensate Water/MEG
0
0
60
Hold at 100%
120
180
240
300
360
420
480
540
600
660
720
780
84
79
