trainig Report for iocl

VOCATIONAL TRAINING REPORT [11-JUNE-2012 TO 6-JULY-2012] [BARAUNI REFINERY, INDIAN OIL CORPORATION LTD]

(IN HARMONY WITH NATURE)

ASHISH KUMAR JHA S4, CHEM. ENGG. IT. GGV (C.G.)

Vocational Training Report

June July 2012

ACKNOWLEDGEMENT

Before proceeding with the detail of the report, I thank the almighty God for making my vocational training a successful one. I would like to thank Mr. A.K.Biswas (CTRO) and Miss Madhushree Maji (STRO), for letting me enjoy this experience of getting trained at Barauni Refinery, Indian Oil Corporation Ltd. It has helped me fully and has grown up my knowledge. Besides, I would like to thank the officials of Barauni Refinery, Indian Oil Corporation Ltd for providing me a good environment and facilities to complete my training. I am also thankful to technicians and field operators and other staff of training department who spared their valuable time and took effort explaining the working of various units of the plant. I am greatly thankful to for their co-operation. I was thoroughly guided by them throughout my training .The information provided to me by them have helped me a lot and would also help me in my long run too .The tremendous effort put by them have motivated me and made me gain confidence in completing this report.

Ashish Kumar Jha S4, CHEM. ENGG. IT.GGV

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Ashish Kumar Jha, B.Tech, CHEM, IT.GGV


June July 2012

ACKNOWLEDGEMENT

Before proceeding with the detail of the report, I thank the almighty God for making my vocational training a successful one. I would like to thank Mr. A.K.Biswas (CTRO) and Miss Madhushree Maji (STRO), for letting me enjoy this experience of getting trained at Barauni Refinery, Indian Oil Corporation Ltd. It has helped me fully and has grown up my knowledge. Besides, I would like to thank the officials of Barauni Refinery, Indian Oil Corporation Ltd for providing me a good environment and facilities to complete my training. I am also thankful to technicians and field operators and other staff of training department who spared their valuable time and took effort explaining the working of various units of the plant. I am greatly thankful to for their co-operation. I was thoroughly guided by them throughout my training .The information provided to me by them have helped me a lot and would also help me in my long run too .The tremendous effort put by them have motivated me and made me gain confidence in completing this report.

Ashish Kumar Jha S4, CHEM. ENGG. IT.GGV

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June July 2012

CONTENT

Title

Page No

Acknowledgement

1

Introduction

3

Fire & Safety

7

Catalytic Reforming Unit

10

Atmospheric Vacuum Unit I/II

17

Atmospheric Vacuum Unit III

25

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CHAPTER 1 INTRODUCTION Company History The Indian Oil Corporation Ltd. operates as the largest company in India in terms of turnover and is the only Indian company to rank in the Fortune "Global 500" listing. The oil concern is administratively controlled by India's Ministry of Petroleum and Natural Gas, a government entity that owns just over 90 percent of the firm. Since 1959, this refining, marketing, and international trading company served the Indian state with the important task of reducing India's dependence on foreign oil and thus conserving valuable foreign exchange. That changed in April 2002, however, when the Indian government deregulated its petroleum industry and ended Indian Oil's monopoly on crude oil imports. The firm owns and operates seven of the 17 refineries in India, controlling nearly 40 percent of the country's refining capacity.

Indian Oil Corporation Limited is India’s largest company by sales with a turnover of

Rs. 3,28,744crores($ 72,125 million) and profit of Rs. 7445 crores ($ 1,633 million) for the year 2010-11.

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June July 2012

Barauni Refinery

Barauni Refinery was built in collaboration with Russia and Romania.situated 125 kilometers from Patna, it was built with an initial cost of Rs. 49.40 crores. Barauni refinery was commissioned in 1964 with a refining capacity of 1 million metric Tonnes per annum and it was dedicated to Nation by then Union Minister for petroleum, Prof. Humayun Kabir in January 1965. After De-bottlenecking, revamping and expansion projects, its capacity today is 6 MMTPA. Matching secondary processing facilities such ResidFluidised Catalytic Cracker (RFCC), Diesel Hydrotreating (DHDT), Sulphur Recovery Unit (SRU) have been added. Barauni refinery was initially designed to process low Sulphur Crude Oil (Sweet Crude) of Assam. Hence sweet crude is being sourcedfrom African, South East Asian and Middle East countries like Nigeria,Iraq,and Malaysia. The refinery receives crude oil by pipeline from Paradeep on the eastern coast via Haldia. Theses state of the art eco-friendly technologies have enabled the refinery to produce environment- friendly green fuels complying with international standards.

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June July 2012

Fig. Flow Sheet of Plant

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Process Units

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AVU-I

:

ATMOSPHERIC & VACUUM UNIT-1

AVU-II

:


AVU-III :


PEU

: PHENOL EXTRACTION UNIT

SDU

: SOLVENT DEWAXING UNIT

CCU

: COKE CALCINATION UNIT

NSU

: NAPTHA SPLITTER UNIT

CRU

: CATALYTIC REFORMER UNIT

RFCCU

: RESID FLUID CATALYTIC CRACKING UNIT

DHDT

: DIESEL HYDROTREATER UNIT

HGU

: HYDROGEN GENERATION UNIT

SRU

: SULPHUR RECOVERY UNIT

ARU

: AMINE REGENERATION UNIT

SWS

: SOUR WATER STRIPPER



June July 2012

CHAPTER 2 FIRE AND SAFETY DEPARTMENT Fire safety refers to the precaution that are taken to prevent or reduce the likelihood of a fire that may result in death, injury or property damage, alert those in a structure to the presence of fire in the event one occurs, better enable those threatened by a fire to survive, or to reduce the damage caused by a fire. Fire safety measures include those that are planned during the construction of a building or implemented in structures that are already standing. Threats to fire safety are referred to as fire hazards. A fire hazard may include a situation that increases the likelihood a fire may start or may impede escape in the event a fire occurs. Some common fire hazards are: 1. Electrical systems that are overload, resulting in hot wiring or connection. 2. Combustibles storage areas with insufficient protection. 3. Combustibles near equipment that generates heat, flame, or sparks. 4. Candles, Flammable liquids and Smoking (Cigarattes, cigars, etc). 5. Fireplace chimneys not properly or regularly cleaned. 6. Heating appliances – stoves, ovens, furnaces, boilers, heaters. 7. Electrical wiring in poor condition. 8. Batteries.

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Barauni Refinery is very hazardous plant among all plants due to production of all kinds of petroleum products that are highly inflammable. Therefore safety is very essential for the refinery. It is the policy of the corporation that every reasonable effort shall be made to provide and ensure safety inside the plant. To ensure safety and to have a safe workplace the employees shall follow safety regulations that are made by Fire and Safety Department of IOCL, Barauni Refinery.

Fire and Safety Plans 1. Key contact information 2. Utility services(including shut off valve for water, gas and electric) 3. Access issues 4. Dangerous stored materials 5. Location of people with special 6. Connection to sprinkler system 7. Layout, drawing and site plan of building 8. Maintenance schedule for life safety systems 9. Personal training and fire drill procedure

Safety Rules and Regulations: 1. Smoking in battery area is prohibited.

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June July 2012

2. Taking matchsticks, lighter etc. inside the battery area are strictly prohibited. 3. Never work inside the plant without helmet in specific area. 4. Only flame proof safety torches/hand lamps tube used.

Safety in Petro Chemical Industry Petro Chemical industry is a bulk business! This means that the output is huge, but the number of processes, which are same worldwide, is rather low. Therefore, groups and corporation have standardized their procedures and processes to a very high degree and implemented their own safety rules and regulation. The aim is to identify the main toxic and explosive substances arising during operations at an early stage thus reliably protecting man, environment and equipment. Special safety requirements have to be considered in times of shutdowns which are carried out on a regular basis. It is no surprise that operators of refineries on all continents rely on dragger solution – some for several decades. Cleaning – Distilling – Converting: in refineries these three processes utilized to produce main products from crude oil, whereby the majority of the production is diesel, domestic fuel oil and gasoline.

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CHAPTER-3 CATALYTIC REFORMING UNIT(CRU) Introduction Catalytic reforming is a chemical process used to convert petroleum refinery naphthas, typically having low octane ratings, into high-octane liquid products called reformates which are components of high-octane gasoline (also known as high-octane petrol). Basically, the process re-arranges or re-structures the hydrocarbon molecules in the naphtha feedstocks as well as breaking some of the molecules into smaller molecules. The overall effect is that the product reformate contains hydrocarbons with more complex molecular shapes having higher octane values than the hydrocarbons in the naphtha feedstock. In so doing, the process separates hydrogen atoms from the hydrocarbon molecules and produces very significant amounts of byproduct hydrogen gas for use in a number of the other processes involved in a modern petroleum refinery. Other byproducts are small amounts of methane, ethane, propane, and butanes. This process is quite different from and not to be confused with the catalytic steam reforming process used industrially to produce various products such as hydrogen, ammonia, and methanol from natural gas, naphtha or other petroleum-derived feedstocks. Nor is this process to be confused with various other catalytic reforming processes that use methanol or biomass-derived feedstocks to produce hydrogen for fuel cells or other uses.

Reaction Chemistry

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There are many chemical reactions that occur in the catalytic reforming process, all of which occur in the presence of a catalyst and a high partial pressure of hydrogen. Depending upon the type or version of catalytic reforming used as well as the desired reaction severity, the reaction conditions range from temperatures of about 495 to 525 °C and from pressures of about 5 to 45 atm. The commonly used catalytic reforming catalysts contain noble metals such as platinum and/or rhenium, which are very susceptible to poisoning by sulfur and nitrogen compounds. Therefore, the naphtha feedstock to a catalytic reformer is always pre-processed in a hydrodesulfurization unit which removes both the sulfur and the nitrogen compounds. The four major catalytic reforming reactions are: 1: The dehydrogenation of naphthenes to convert them into aromatics as exemplified in the conversion methylcyclohexane (a naphthene) to toluene (an aromatic), as shown below:

2: The isomerization of normal paraffins to isoparaffins as exemplified in the conversion of normal octane to 2,5-Dimethylhexane (an isoparaffin), as shown below:

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3: The dehydrogenation and aromatization of paraffins to aromatics (commonly called dehydrocyclization) as exemplified in the conversion of normal heptane to toluene, as shown below:

4: The hydrocracking of paraffins into smaller molecules as exemplified by the cracking of normal heptane into isopentane and ethane, as shown below:

The hydrocracking of paraffins is the only one of the above four major reforming reactions that consumes hydrogen. The isomerization of normal paraffins does not consume or produce hydrogen. However, both the dehydrogenation of naphthenes and the dehydrocyclization of paraffins produce hydrogen. The overall net production of hydrogen in the catalytic reforming of petroleum naphthas ranges from about 50 to 200 cubic meters of hydrogen gas (at 0 °C and 1 atm) per cubic meter of liquid naphtha feedstock. In the United States customary units, that is equivalent to 300 to 1200 cubic feet of hydrogen gas (at 60 °F and 1 atm) per barrel of liquid naphtha feedstock. In many petroleum refineries, the net hydrogen produced in catalytic reforming supplies a significant part of the hydrogen used

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elsewhere in the refinery (for example, in hydrodesulfurization processes). The hydrogen is also necessary in order to hydrogenolyze any polymers that form on the catalyst.

Process Description The most commonly used type of catalytic reforming unit has three reactors, each with a fixed bed of catalyst, and all of the catalyst is regenerated in situ during routine catalyst regeneration shutdowns which occur approximately once each 6 to 24 months. Such a unit is referred to as a semi-regenerative catalytic reformer (SRR). Some catalytic reforming units have an extra spare or swing reactor and each reactor can be individually isolated so that any one reactor can be undergoing in situ regeneration while the other reactors are in operation. When that reactor is regenerated, it replaces another reactor which, in turn, is isolated so that it can then be regenerated. Such units, referred to as cyclic catalytic reformers, are not very common. Cyclic catalytic reformers serve to extend the period between required shutdowns. The latest and most modern type of catalytic reformers are called continuous catalyst regeneration reformers (CCR). Such units are characterized by continuous in-situ regeneration of part of the catalyst in a special regenerator, and by continuous addition of the regenerated catalyst to the operating reactors. As of 2006, two CCR versions available: UOP's CCR Platformer process and Axen's Octanizing process. The installation and use of CCR units is rapidly increasing. Many of the earliest catalytic reforming units (in the 1950s and 1960s) were nonregenerative in that they did not perform in situ catalyst regeneration. Instead, when needed, the aged catalyst was replaced by fresh catalyst and the aged catalyst was shipped to catalyst Page 13 of 30



June July 2012

manufacturers to be either regenerated or to recover the platinum content of the aged catalyst. Very few, if any, catalytic reformers currently in operation are non-regenerative. The process flow diagram below depicts a typical semi-regenerative catalytic reforming unit.

Fig. Schematic diagram of a typical semi-regenerative catalytic reformer unit in a petroleum refinery The liquid feed (at the bottom left in the diagram) is pumped up to the reaction pressure (5 to 45 atm) and is joined by a stream of hydrogen-rich recycle gas. The resulting liquid-gas mixture is preheated by flowing through a heat exchanger. The preheated feed mixture is then totally vaporized and heated to the reaction temperature (495 to 520 °C) before the vaporized reactants enter the first reactor. As the vaporized reactants flow through the fixed bed of catalyst in the reactor, the major reaction is the dehydrogenation of naphthenes to aromatics (as described earlier herein) which is highly endothermic and results in a large temperature decrease between the inlet and outlet of the reactor. To maintain the

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required reaction temperature and the rate of reaction, the vaporized stream is reheated in the second fired heater before it flows through the second reactor. The temperature again decreases across the second reactor and the vaporized stream must again be reheated in the third fired heater before it flows through the third reactor. As the vaporized stream proceeds through the three reactors, the reaction rates decrease and the reactors therefore become larger. At the same time, the amount of reheat required between the reactors becomes smaller. Usually, three reactors are all that is required to provide the desired performance of the catalytic reforming unit. Some installations use three separate fired heaters as shown in the schematic diagram and some installations use a single fired heater with three separate heating coils. The hot reaction products from the third reactor are partially cooled by flowing through the heat exchanger where the feed to the first reactor is preheated and then flow through a water-cooled heat exchanger before flowing through the pressure controller (PC) into the gas separator. Most of the hydrogen-rich gas from the gas separator vessel returns to the suction of the recycle hydrogen gas compressor and the net production of hydrogen-rich gas from the reforming reactions is exported for use in the other refinery processes that consume hydrogen (such as hydrodesulfurization units and/or a hydrocracker unit). The liquid from the gas separator vessel is routed into a fractionating column commonly called a stabilizer. The overhead offgas product from the stabilizer contains the byproduct methane, ethane, propane and butane gases produced by the hydrocracking reactions as explained in the above discussion of the reaction chemistry of a catalytic

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June July 2012

reformer, and it may also contain some small amount of hydrogen. That offgas is routed to the refinery's central gas processing plant for removal and recovery of propane and butane. The residual gas after such processing becomes part of the refinery's fuel gas system. The bottoms product from the stabilizer is the high-octane liquid reformate that will become a component of the refinery's product gasoline.

Catalysts And Mechanisms Most catalytic reforming catalysts contain platinum or rhenium on a silica or silicaalumina support base, and some contain both platinum and rhenium. Fresh catalyst is chlorided (chlorinated) prior to use. The noble metals (platinum and rhenium) are considered to be catalytic sites for the dehydrogenation reactions and the chlorinated alumina provides the acid sites needed for isomerization, cyclization and hydrocracking reactions. The activity (i.e., effectiveness) of the catalyst in a semi-regenerative catalytic reformer is reduced over time during operation by carbonaceous coke deposition and chloride loss. The activity of the catalyst can be periodically regenerated or restored by in situ high temperature oxidation of the coke followed by chlorination. As stated earlier herein, semiregenerative catalytic reformers are regenerated about once per 6 to 24 months. Normally, the catalyst can be regenerated perhaps 3 or 4 times before it must be returned to the manufacturer for reclamation of the valuable platinum and/or rhenium content

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June July 2012

CHAPTER -4 ATMOSPHERIC AND VACUUM DISTILLATION UNIT (AVU-I/II) Introduction There are two Atmospheric and Vacuum Distillation Units in Barauni Refinery numbered as AVU-I and AVU-II, each were designed for 1 MMT/year crude processing. Subsequently another distillation unit without vacuum distillation facility was added. This unit was designed for 1 MMT/year of crude and known as AU-3. Crude Processing capacity of both units AVU-I & AVU-II was increased to 1.6 MMT/year by HETO project (Heat Exchanger Train optimization) in 1990. The above modification (HETO project job was designed by EIL (Engineer's India Limited) and fabrication/erection job was completed by M/s. Pethon Engg. Ltd, Mumbai. The units were again revamped in 1998 (M & I) when the capacity was expanded to 2.1 MMT/year of each of the two units. Through these units were designed on the basis of evaluation data of Naharkatiya crude, presently the units have switched on to imported crude due to none availability of Assam crude.

Process Description Crude oil (imported) is received from Haldia by pipeline and is pumped from tanks through

Heat Exchangers after exchanging heat with various hot stream, the crude streams

attain a temperature of approx. 393K to 403K. After attaining temperature about 393K to

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June July 2012

403K the two crude flows combine together and enter in desalter for separation and removal of water and salt. Bi electric desalter is having two energised electrodes. A distributor head splits crude between the upper and lower pair of electrodes. Crude oil separated from water between the centre and lower electrodes passes through the upper electrode in a converging countercurrent flow with the separating water from upper set of electrodes. This creates a second washing zone for half of the feed in a strong electrical field thereby causing maximum salt removal efficiency. The two desalter in AVU-I &II are PETRECO BIELECTRIC type which were commissioned in the year 2001.

Post Desalter At the outlet of Desalter there are two booster pumps which boost up the crude at discharge pressure around 15 kg/km.Pre-topping column has 20 Trays (All valve trays with a bed of packing between 9th & 10th tray) and operates on operating conditions.

Pretopped crude stream passes through heat exchangers. After exchanging heat with various hot products the pretopped crude flows combine and it is segregated again near furnace in two pass flows before entering the atmospheric heater for further heating and finally fed to

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June July 2012 o

6th tray of main column through two entry nozzles at 340 C.The Furnace is provided with Air Preheater. Main Fractionating Column has 43 double pass valve trays. Following are the operating parameters of the main column.

As per design two types of gas oil, one light and other heavy were supposed to be th

th

th

th

withdrawn light gas oil from 6 and 18 tray and heavy gas oil from 8 /10 trays at 140-300 o

o

o

C and 300-350 C respectively. At present gas oil is withdrawn as 250-370 C cut from

16th/18th tray. The existing 7

th

th

to 14 double pass channel trays were replaced with valve

trays in HETO,1990. Since 1970 heavy gas oil withdrawal was stopped. Main Column bottom is feed to vacuum column .

Vacuum Distillation Vacuum distillation is a method of distillation whereby the pressure above the liquid mixture to be distilled is reduced to less than its va por pressure (usually less than atmospheric pressure) causing evaporation of the most volatile liquid(s) (those with the lowest boiling points). This distillation method works on the principle that boiling occurs when the vapor pressure of a liquid exceeds the ambient pressure. Vacuum distillation is used with or without heating the solution. Vacuum distillation increases the relative volatility of the key

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June July 2012

components in many applications. The higher the relative volatility, the more separable are the two components; this connotes fewer stages in a distillation column in order to effect the same separation between the overhead and bottoms products. Lower pressures increase relative volatilities in most systems. A second advantage of vacuum distillation is the reduced temperature requirement at lower pressures. For many systems, the products degrade or polymerize at elevated temperatures. Vacuum distillation can improve a separation by: 1. Prevention of product degradation or polymer formation because of reduced pressure leading to lower tower bottoms temperatures, 2. Reduction of product degradation or polymer formation because of reduced mean residence time especially in columns using packing rather than trays. 3. Increasing capacity, yield, and purity. Another advantage of vacuum distillation is the reduced capital cost, at the expense of slightly more operating cost. Utilizing vacuum distillation can reduce the height and diameter, and thus the capital cost of a distillation column. Reduced crude from main column bottom at a temperature of approx. 330 oC is pumped through Furnace. The Furnace coil outlet (4 passes) combines in one header and enter into vacuum column at 4th plates through two entry nozzle. Coil outlet temperature is maintained at about380 oC. Operating condition of Vacuum Column are as follows :

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Stabilizer Column Unstabilised gasoline is pumped to 16th/20/24th tray of Stabiliser. Feed temperature is about 110o C. The column has 35 valve trays. Operating conditions of Stabiliser are:-

LPG Caustic Wash LPG caustic wash facilities were provided in AVU-II and was first commissioned in Sept,1984 where LPG of AVU – I, AVU-II is washed with caustic solution of 10-12%, strength.

Heavy Naptha Heavy Naphtha is drawn from main column ,36th tray, through stripper. Operating parameters:Page 21 of 30



June July 2012

Product Streams Example of AVU-I/II:-

Tempered Water Facilities (Heto - 1990) During HETO, tempered water facility was provided in AVU-2 . Tempered water is used as cooling media in S.R. cooler instead of Pressurised cooling water as is being used in conventional coolers. This facility is common for both AVU-1 & AVU-2. Tempered water is steam condensate, received from condensate recovery system of refinery, with neutral ph

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value after chemical treatment. Use of tempered water in cooler prevents the sealing and corrosion in cooler tubes thus ensuring the very efficient cooling of product (S.R.) and minimising to a great extent the maint. of the cooler. Tempered water facility is essentially a closed circulating system in which the loss of tempered water during circulation is very negligible.

Corrosion Control Ammonia is injected in the form of aquous solution for preventing HCL corrosion in pretopping and main column overheads. Recent modification of this system is the installation of on line pH meters for measuring pH in both the units.

Ahuralan Injection Ahuralan is the trade name of an organic inhibitor compound, used for preventing corrosion of condenser shell. It prevents corrosion by forming a thin protective layer on the equipment. A 5% W/V and 2% W/V solutions are

prepared in AVU-I and AVU-II

respectively. Injection rate in both the units is 5 PPM of overhead contents.

Major Equipment 1.

Tubular Furnaces:- Tubular furnace is cylindrical type for pretopping and

vacuum sections. It is box type for the main distillation column. The furnaces have sections called "Radiation Section" and convection section. A part of the tube in convection zone is for super-heating steam( used in the process) and the rest is used for heating the oil in tubes. The inside walls of the furnace are protected against the temperature effects by a refractory insulation to reduce the outside heat losses. The bottom bed show openings in which burners Page 23 of 30



June July 2012

are placed. The flue gases go out of the furnace thorough the stack. The stack is protected inside, in its lower part where the flue gases are still very hot by a wall of refractory bricks. A damper is located at its base to allow the regulation of the draft. This damper is built with steel suitable for the flues gases temperature. 2.

Burners :- The burner is conceived to burn either gas or oil. Gas burners are of

two types: either with pre-mixing or without premixing. In the first type a part of the combustion air is mixed with the fuel gas before this has reached the injector nozzle of the burner. The burners without premixing give a diffusion flame, the combustion air entering the furnace in a parallel direction with the gas jet and slowly diffusing in it. AVUs gas burners are of this type. They give a longer and more luminous flame than those with premixing. AVUs burners are of inside-mix type. In these, the steam and oil are mixed in a chamber within the burners, and they issue together from the burner as a single stream. Foam formed in the mixing chamber is directed by the shape and direction of the burner tip so that the flame is of proper shape and size for the furnace box.The burners with spraying by steam have a flexibility much higher than those with mechanical spraying

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CHAPTER 6 ATMOSPHERIC AND VACUUM DISTILLATION UNIT III The Process Description Crude Preheat Crude is pumped to desalter through two parallel passes in Pre-Desalter Heat Exchanger Train-1. The first pass consists of four nos. of heat exchangers: The second pass of heat exchangers also has four nos. of heat exchangers: Both the passes combine in a single header and enter the desalter.

Desalter Circuit A static Mix valve and a control valve is provided for mixing water and demulsifier with crude prior to entry into the desalter. The desalter pressure is controlled at around 9.0 Kg/cm2 (g) The desalted crude is pumped to Pretopping Column .

Heat Exchanger Train II The discharge is through a series of heat exchangers (6 Nos.). In this network of heat exchangers, crude is heated by outgoing products to a temperature of around 230 °C.

Pretopping Column The desalted crude at 230ºC enters the columns for withdrawal of unstabilised gasoline and heavy naptha. Page 25 of 30



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Heat Exchanger Train III The bottom product at a temperature of around 250 °C is pumped to furnace through heat exchangers and then after combining is routed in parallel streams through pre-heat exchangers (3 Nos). The preheat temperature at the exit is around 270 °C. Part of the bottom product coming out of the heat exchanger train is sent to Pretopping Column as heat input. The coil outlet temperature of the furnace is maintained at around 360 °C. Pre topping column bottom product is sent through the main furnace. The coil outlet temperature is maintained at around 360°C.

Main Fractionator The main column is provided with: 1.

Valve trays in the top section,

2.

KERO / LGO section,

3.

Structured packing in LGO / HGO section,

4.

The bottom stripping section and

5.

Over-flash section.

6.

The column bottoms (RCO) is flashed into the Vacuum Column.

Stabiliser Section Part of the condensed overhead gasoline is pumped through heat exchanger to stabiliser section.

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LPG Caustics Wash

LPG goes to LPG caustic wash-vessel after mixing with caustic. VACUUM SECTION The Vacuum column is provided with structured packing in LVGO pumparound section, LVGO/HVGO fractionation section, HVGO pumparound section, and Wash section and valve trays in the bottoms stripping section. The column is operated at a top pressure of 70 mm Hg. K-301 top is provided with a demister to minimize the entertainment of liquid droplets in the vapour going to overhead-condenser. The side streams of main vacuum column are as under :

This Reboiler Furnace is a vertical cylindrical heater with convection and radiant section. The heater houses 12 nos. of horizontal tubes in convection section and 48 nos. bare tubes 6" NB of A335 P9 material. These 48 tubes are arranged in double pass arrangement giving material total radiant heat transfer area of 248.8 m2. The firing of this heater is done by 4 nos. combination fuel fired forced draft burners provided with pilot burners having

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automatic electric ignition system. Refractory material used in the radiant sanction of this heater is ceramic fiber blanket. Crude heater is a vertical cylindrical heater with convection and radiant sections. The radiant section of the heater houses 88 nos. bare tubes of 6" NB of A335 P9 material. These 88 tubes are arranged in four-pass arrangement giving total heat transfer area of 856.8 M2. In the horizontal convection section there are 24 nos. bare tubes of A335 P9 material and 64 nos. of studded tubes with an extended surface area of 950 M2.In the convection section, there are also 12 nos. of extended surface tubes for steam superheat with an extended surface area of 70 M2. The firing of this heater is done by 8 nos. combined fuel fired forced draft burners provided with pilot burners having automatic electric ignition system. Refraction material used in the radiant section of this heater is ceramic fiber blanket. Vacuum heater F-301 is a vertical cylindrical heater with convection and radiant section. In each pass of the furnace, there is arrangement for introducing turbulising steam at convection section inlet and convection section outlet. The radiant section of the heater houses 54 nos. bare tube of 6" each NB A335 P9 material. These tubes are arranged in two parallel passes giving total heat transfer area of 330 M2.

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trainig Report for iocl

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