internship report giki

8/15/2019 Internship Report giki

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PAK- ARAB REFINERY COMPANY LIMITED

University of Punjab Lahore.

PAK-ARAB COMPANY LIMITED Page 1

Submitted to:

Whom it may concern

Pak-Arab Company limited

Submitted by:

Muhammad Yousaf

Internee #: 04 (TSD)



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Thank you Parco for giving such respect.

For me Parco stands for

P for people who are Friendly.

A for people who are Amazing.

for people who are respectful.

C for people who are truly caring.

O for people who worth’s like ornaments.


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Dedicated to

The One in Whose Hands My Life Is

"And Allah has brought you out from the wombs of your mothers while you know

nothing. And He gave you hearing, sight, and hearts that you might give thanks (to

Allah)"

[Quran, 16:78]


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Acknowledgement:

This report is only made possible due to combine efforts of all the members MCR and specially the

Engineers from Technical Services Department (TSD-MCR) who has given best of their efforts and

available time to make me things clear.

I would like to thank Mr. Khalil Ur rehman and my respective mentor Engineer Muhammad Abubakar

and Imran rasheed the great and kindest of all in the organization and charming personality who

guided me during my entire internship. I have not seen such a versatile and super kind personality in

my life.

Also to the members of HR and TSD department who has provided me the opportunity for internship

and facilities during stay to the internees. Special thanks to following members.

Mr. Khalil ur rehman

Mr. Abubakar

Mr. Imran Rasheed

Mr. Zubair ahmad

Mr. Farooq

Mr. Ameer Gull

Mam khalida

Mr. Usman

Finally, I wish to thank my parents and my all Teachers for their support and encouragement

throughout my study.


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T able Of Contents: General Training:

Introduction to PARCO

Technical Services Department

Health Safety and Environment

Fire Protection Department

Specific Training:

Crude distillation unit 100

Vacuum distillation unit 110

Vis breaking unit 130

Gas concentration unit 411

Nephta hydro treating unit 200

Kero-Merox unit

LPG-Merox unit

Storage tanks

Assignments

All assignments that were assigned are attached with report.


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General Training:

Introduction to PARCO & MCR

Parco

A Pakistan Abu-Dhabi Joint Venture.

Corporate Objectives

To consolidate financial and organizational gains, PARCO purposes the following objectives;

Professional and progressive corporate outlook

Aggressive technical thinking and advanced planning

Reliability of service

C onsistency in performance

Organized and systematic development


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C OMPANY PROFILE:- PARCO! Means ENERGY.

Incorporated in Pakistan in May 1974, as a public limited company, Pak-Arab

Refinery Limited (PARCO) is a joint venture between the Government of

Pakistan (GOP) and Abu Dhabi. Its authorized capital is Rs.15 billion and the

current paid-up capital of PRs. 2.16 billion IS in the process of being raised to

Rs.II.6 billion by the end of year 2002. 60% of the share capital is held by GOP,

and 40% by Abu Dhabi Petroleum Investments (ADPI). In the last 25 years, the

company has expanded a phenomenal 24 times and has achieved an equity

base of over PRs 12 billion and an asset base exceeding PRs. 92 billion or just

over US$ 1.5 billion in current dollar terms.

" An enlightened investment decision in anyone's books!"

It was the first AAA credit rated Company by PACRA in the country and

continues to command that credit worthiness for an unprecedented fifth year-

running. The Management of the Company is vested in a Board often Directors

of which GOP appoints six Directors including the Chairman and the Managing

Director and the remaining four Directors represent ADPI. The Managing

Director is the Chief Executive of the Company and the Federal Ministry for

Petroleum and Natural Resources performs an overview role and represents the

interest of the Government of Pakistan.

PARCO is truly Energy Company.

PARCO as an energy company is the fulcrum and key building block in the

country's strategic oil supply and its logistics. With the synergy of a


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comprehensive and expanding oil pipeline network, integrated with a significant

and modem refining capability, PARCO has emerged as the strategic fuel

supplier to the country. Parco's discrete areas of competitive advantage will

enable it to achieve excellence in Energy transportation through pipelineoperations and management, strategic storage, leading edge refining and

leadership in marketing products through retail and exports.

PARCO Mid-Country Refinery

PARCO is actively involved in various facets of Oil Storage, Transportation,

Refining, Marketing and Export of Energy products. It serves as the lifeline for

transportation of fuel supplies in the country and represents more than 40% of

the indigenous refining capacity. It has the most comprehensive cross-country

oil pipeline and storage network with a 100,000 BPD state-of-the-art refinery

based on latest leading edge refining technology and processes. Commissioned

in the year 2000, a full month ahead of schedule and within the approved

budget of US$ 836 million, the sensibly located ''Mid Country”.

Refinery was formally inaugurated in February, 200I by the Chief Executive of

Pakistan. Besides being the critical inland supplier to the high consumptioncentral and northern areas of Pakistan, PARCO also assists with the balance of

payments of the country. It helps substitute imports of refined value added oil

products to the tune of $100 million annually and has additionally earned more

than US$50 million through exports of quality 90 RON Unleaded Motor Gasoline

and other products to international buyers. PARCO, through leaderships and

technical where withal was successful in introducing unleaded motor gasoline in

the country in June 2001, fully four years ahead of the World Bank

recommended time frame. Future generations of Pakistanis will be thankful for

Having been ensured a much healthier environment and improved quality of life


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With the coming on-stream of the refinery operations, the company has begun

marketing of its fuel products and LPG. Under a Technical Services and Support

Agreement (TSSA), SHY of Holland is marketing25% of the LPG production as

PARCO's brand 'PEARL Gas.' PARCO is also marketing OMY Austria's lubricantsthrough the brand name of 'PEARL Lubes'. PARCO has also entered in to a joint

venture agreement with Total Final lf of France whereby consumer petroleum

products are marketed under the co-branding of TOTALPARCO through a rapidly

emerging national network of retail outlets. Already more than a dozen have

been commissioned in the Punjab, and over the next decade about 500 stations

will be dotted across the country.

Pipeline Network

The refined petroleum products transport logistics on road and rail and the

existing pipeline network. The surface transport mode is potentially hazards to

other traffic, human lives and the environment besides wear and tear of road

surfaces. PARCO’s pipeline network is a safer and more cost effective

alternative for both crude and product transportation. With the completion of

the White Oil Pipeline in about two years, a more comprehensive, safer, cost

effective, demand responsive and eco-friendly pipeline network will be

available to meet the country’s growing needs for energy.

The project facts are summarized below;

Location Qasba Gujrat / Mahmood Kot

Project cost US $886 million


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Main supply and construction contractors JG and Marubeni Corporation

Japan.

Completion Period 36 months

First crude in Pipeline August03, 2000

First crude at Refinery site August25, 2000

First product out September04, 2000

Why PARCO is Mid- Country Refinery?

Petroleum product demand in Pakistan has outstripped local production

Demand in Northern region of Pakistan is more than 60% of Pakistan’s total

requirement Furnace oil being a viscous product cannot be transported over a

long distance in pipeline to meet requirements of power plants in the vicinity of

Mehmood Kot. It is more economical to transport crude oil to Mid-Country

Refinery & produce products including Furnace oil. Indigenous refining

capability brings additional security and the desired flexibility of product supply

with respect to imports.


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PARCO Mid-Country Refinery has a lead of at least 3-4 years on any other

refinery project in the country giving market positioning benefits and ensuring

maximum commercial advantage. Parco’s 1,228-Km cross country pipe line is

already available for crude/product transportations.

Advantages Of This Location for Refinery;

Sensible and strategic location from a commercial and national security point of

view. Server’s major consumption centers catering to a population of 35 million

with a current /projected significant deficit. Is close to located close to power

plants with an annual demand of 1 million tons of Furnace oil.

Parco’s existing infrastructure at Mehmood Kot terminal (TS-2) has been

optimally integrated into the Refinery resulting in cost saving and improved

operations. Streamlines the movement of Crude Oil and petroleum products

thus reducing the burden on country’s rail/road transportation. Is close to

petroleum demand centers giving advantage for the future growth into bulk

petrochemicals. Utility supplies have been secured through adjacent power

plants and there is plenty of water to meet Refinery requirements.

An Overview to PARCO;

The refinery complex include onsite process units beside numerous

offsite/utilities units and other permanent facilities with tanks to store the

crude oil, intermediate feeds stocks and finished products.

• H ealth Safety and Environment


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Why Health Safety and environment?

Accidents can take place anywhere around the world. These accidents affect

profit, company’s reputation and environment. There is no budget assigned to

these unpredicted incidents. Over the years, numerous oil companies have

encountered major accidents which resulted loss of billions of dollars and

loss of many lives. Let’s put some light on some of the major accidents

hitting oil and gas sector around the world. Some of the disasters are as

follow

• Piper Alpha 1988

– Explosion, Oil and Gas caught fire on the rig

– 167 workers killed

– 1.7 billion pound of property damage

• BP Texas Refinery 2005

– Dangerous gases level emitted

– 8 warnings given by the government

– System over pressured, liquid erupted

– 17 people killed


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– US $ 1.3 billion

• BP’s Deep -water Horizon Oil Spill 2006

– Wellhead Blowout

– Fire on Oil Rig

– 4.9 million barrels of oil spilled in the Gulf of Mexico

– 11 people killed

– US $20 billion spent on recovery

Above given examples tell us about the consequences a company might have to

suffer in case of an accident. It is evident that there is a dire need of a

department which can help minimize the chances of an accident, which does

regular auditing of the safety around the plant area and which can put a strong

check on the implementation of rules at the refinery area.

PARCO HSE department policy statement “PARCO is committed to enhance

customer satisfaction through continual improvement, operational excellence

and in time delivery of quality products while remaining watchful over the

safety, health and environmental concerns of its employees, contractors and

the general public associated with it.”

Furthermore HSE policy ensures the provision of health and safety of its

employees and maintains an ecological balance is the responsibility of the

company. The department is not only concerned for the company’s employees

and the refinery area, but it is also consistent in protecting the people living

outside PARCO, minimizing hazards, creating a safe atmosphere to work at.


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In order to guide the employees regarding their safety, HSE conducts regular

seminars and training sessions so that the employees are prepared to handle

any kind of challenging situation at the refinery area.

VISION: We aim to be an organization where individual and collective effort

achieves outstanding HSE performance, evident for all to see. HSE is treated at

par with productivity and profitability. HSE policy statement recognizes that the

provision of health and safety of its employees and maintain an ecological

balance is the responsibility of the company.

• FIRE MANAGEMENT SYSTEM

Fire is a potential hazard, especially in hydro-carbon industry such as PARCO. It

is very crucial for these organizations to have Fire Management System in order

to minimize losses and overcome fire as soon as possible in case of a fire

accident. A Fire Management System includes;

– Fire Detection, Prevention and Suppression

– Emergency Response

– Fire Fighting

HSE ensures Fire Prevention system by;

– Work Permit Procedures; No activity in plant area can be done without getting

Work permit from the relevant authorities

– Regular tests and audits of fire equipment

– Installing lightening arrestors at plant

– Classification of hazardous areas


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– Use of intrinsically safe equipment; equipment (might be electronic) which are

fully covered with insulation and do not pose any threat to a hydro carbon

refinery area

– Apart from IS equipment, no electronic device is allowed inside the plant area.

– No worker can carry lighter or matchsticks inside the plant area.

– For smokers, isolated and safe smoking booths are installed at numerous

points in the plant area.

– Use of Floating roof tanks for storage purposes. The roof rises and falls with

the liquid level in the tank.

• Fire Detection

Different kinds of detectors are installed around the plant area to detect release

of any dangerous hydrocarbon or detect fire at plant are;

– Smoke Detector

– Heat Detector

– Hydrocarbon Detector

– Infra-Red Flame Detector

• Fire suppression


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Suppression systems use a combination of dry chemicals and/or wet agents to

suppress equipment fires. Following is a list of Fire Suppression systems and

equipment used at PARCO;

• Fire Extinguishing Methods

Parco has state of the art equipment to fight a fire with a complete fire brigade

squad ready 24 hours for firefighting operation. Following is a list of firefighting

equipment;

– Fire Brigade Trucks

– Fire Hoses installed at different spots including storage tanks area

– A network of water Pipeline (red colored) which covers almost every spot of

the area and is fully pressurized by 2 Jockey pumps. In case of fire, rest of the 4

main pumps start within 10 seconds one after the other.

– Above mentioned pipeline is used to refill fire brigades, fire suppression

system, hoses etc.

– Foam tanks

– Fire hydrants

– Fire suits

– Fire extinguishers

– Ladders

– Fire Drills


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• Emergency Response

In MCR, there is a well-established accident response system. Following are the

vital components of the communication system for emergency at MCR;

– Manual Call Point

– Telephone (emergency # 4000 or 11)

– Radio communication (Motorola)

– Fire Alarm Panel

• Emergency Alarm

In case of Emergency HSE turns on the master alarm which has a sinusoidal

sound wave and goes on for about two minutes. As soon as the fire alarm goes

on, each employee is supposed to rush to the respective assembly point

assigned for each area at MCR.

Onsite Process Units and their Capacities

Unit

Code Unit Cap(BPSD)

100 crude distillation 100,000


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110 Vacuum distillation 42,800

200 Naphtha hydro treating 25,600

300 CCR Plat former 16,350

284 Dieselmax 22,450

130 Visbreaker 15,560

801 Kerosene Merox 20,000

802 LPG Merox 4,500

411 Gas Concentration 22,050(liquid)

11,242(Gas/MMSCR)

810 Amine Treating 7,721(FG/MMSCR)

9,963(sws)

820 Sulfur Recovery 115 MTPD

T ECHNICAL SERVICESDEPARTMENT (TSD)

Mission Statement:-


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Support production targets and Meet future challenges in industry, while

Ensuring trouble free Economical operations in All instances by adopting Best

practices & Improvements in technology on Sustainable basis.

Main functions:-

Support Refinery operation to meet the production targets at optimum

cost.

Quality control of intermediate and product streams.

Troubleshooting and debottleneck studies.

Turnaround planning and execution of various special activities.

Advice and assist in technology upgrades, plant modifications and future

projects.

Management/coordination of Technical Review for CRs & QRI systems.

Preparation of Monthly Progress Report of Refinery Performance.

The technical services department has three sections:

Process Engineering Section

Production Planning & Oil Accounting Section

Laboratory


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P rocess Engineering Section:

The process engineering section is responsible for the trouble shooting,

monitoring of the Refinery Operation and also to give the technical assistance

for further improvements.

The department is directly concerned with the on-site units, which include:

1. Crude Distillation Unit

2. Vacuum Distillation Unit

3. Gas Concentration Unit

4. Visbreaker Unit

5. Dieselmax Unit

6. NHT/CCR/Platformer

7. Meroxes

8. Amine treating Unit

9. Sulfur recovery unit

10. DHDS

11. AABU

12. Storage tanks


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Laboratory section:The MCR has got well-equipped laboratories some of which are listed as under:

Diesel Lab:

Following tests are being carried out in the laboratory:

Distillation Flash point

Pour point

Specific Gravity

Viscosity

Octane Analyzer Room:

The research octane number of naphtha is tested.

Water Laboratory:

The pH, hardness SiO2 content, conductivity etc. of water is tested prior to

feeding the water to the boiler.

Ca2+, Mg2+ ions are tested by titration.

Introducing ammonium molybedate to water checks SiO2 content.

Respective meters check conductivity and ph.

Jet Fuel and Gasoline Lab:


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Flash points are measured using Abel closed cup apparatus. Corrosion tests are

carried out using copper strips in copper corrosion bath. Jet Fuel Thermal

Oxidation Stability Test is carried out.

Gas Chromatography Lab:

Gas chromatography is carried out for the PONA test (paraffin’s, olefins,

naphthenic, and aromatics) of the sample of naphtha.

LPG Lab:

Weathering tubes are used to measure the evaporation temperature of the LPG.

95% of LPG should evaporate at not more than 4.4degC.

Atomic Absorption Lab:

Trace metals e.g. Li, K, Zn, Na, Fe are detected on basis of absorption using

spectrophotometer.

Overall refinery process:-

The overall refinery process flow sheet diagram,


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C rude Distillation Unit(unit 100):

The crude distillation is design to process 100,000 BPSD of crude. The feed of

this unit is:

100% Arabian light crude

70% upper Zakum and 30% Murban crude oil

The crude distillation unit consists of the following sections;

Crude charge and pre-heat section.

Crude de-salter section.

Crude charge heater section.

Crude column and site cut product section.

The unit functions to separate the crude oil into different cuts: naphtha,

kerosene, diesel and reduced crude. These cuts are further processed to

the gas concentration unit, Kero-merox unit and for blending and vacuum

distillation unit.

Arabian light, upper zakum and murban crude oil coming from Karachi

To Mahmood Kot via several kilometers pipe line is coming to the unit

Crude distillation.

All the crude contains salt water together with sediment depend upon the area

from which the crude is produced


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Salt content is reported as pounds of salt per thousand barrels of oil.

Old method heating of oil was settling or addition of chemicals before settling.

But now a day a new method has been introduced named as Electrical desalting.

It is a two stage process

Emulsion of crude oil and water ( mixing )

Demulsification ( breaking)

Approximately 95% of salt is present in base sediment of crude.

The emulsion is produced by passing the liquids at high velocity through theorifice or b/w the fixed surfaces.

This is accomplished by a mixing valve upstream of the electric desalter or by

injecting the water at the start of exchanger train that proceeds to the desalter

Greater the pressure drop greater will be mixing.

Low velocity desalter

It is used where oil contains 50% of salt in continuous phase of crude oil. Oil

passing through the distributor and then upward at relatively low velocity

through electrodes.

Initial coalescence takes place between the oil water interphase and lower

electrode and final coalescence takes place where the drops coalesce and

Becomes large and fall against the upward flow of oil to the bottom with thegravity action.

The oil interphase is controlled by the interface level controller which bleeds the

water from bottom of the tank and the clean crude oil from top.


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High velocity desalter

It is used for stable emulsions and having the same elements as low velocitydesalter. We use high velocity because the emulsion particles can form a chain

between the electrodes and can cause a short circuit.

In crude distillation unit low velocity desalter is used.

From the desalter the heat is then proceed to the fire heaters and gain the

require heat before entering to the crude distillation unit.

The temperature of the feed can vary from 315 oC. To 427 oC.

Then after heating in fire heaters the crude enter in the flash zone of

fractionation column.

There are 40 trays into the distillation unit some of the material flashes into

vapor which rises up to the column.

Rest of the feed goes down with the trays. Steam from near the 40th tray is

introduce into the column which goes upward taking with the lighter ands and

heavier ends collected at the bottom.

There is accumulative tray between 27

th

and 28

th

tray from which the diesel isstripped and there is another accumulator tray between the 15th and 16th tray

from which the kerosene is stripped similarly from between the 4th and 5th

accumulator tray the unstabilized naphtha is stripped.

The overhead vapors are carried out of crude column and pass through the

condenser where all of the steam and gasoline vapors are condensed into the

liquid.

A portion of the liquid is sent to the fractionator as top reflux while rest of netliquid overhead is pumped to the gas concentration process unit.

And the uncondensed gas from the overhead is sent to the Gas concentration

unit.

All products are cooled before being sent to the storage.


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This is accomplished by the use of heat exchange with crude oil feed, air fin

coolers and trim coolers and also circulating cooling tower water with

exchangers.

The lighter products should be cold before send to the storage to reduce vaporlosses in storage tanks but the heavier products not need to be cold as they can

b use as feed to another unit depending upon the unit inlet temp we can use it.

A product must never leave with a temperature 100 oC. If there is any

possibility of it passing through the tank containing water the hot product can

boil the water and forming the steam which can blow off the roof of tank.

The block diagram of the crude distillation unit is given as,


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V acuum Distillation Unit:To achieve maximum recovery of gas oil from crude we introduce it into the

vacuum distillation column. The vacuum residue is designed to process the

atmospheric residue of either Arabian light crude oil or upper zakum and

murban crude oil blend. The processing capacity of vacuum distillation is 42,800

BPSD

The feed of the vacuum distillation unit is

100% Arabian light Crude residue 70/30% volume blend of Upper Zakum and Murban crude residue

The unit is composed of the following sections;

Vacuum charge heater section

Flash zone section

Product condensation

Heat exchangers

Reduced Crude from the CDU is charged to the VDU through vacuum

heaters at less pressure. Distillation takes place in the presence of

vacuum to prevent degradation of reduced crude. Temperature should

not be so high that cracking does not take place if this happens then it is

necessary to lower the temperature. Flash zone temperature widely

depends on the crude source.

Flash zone section is the section residue of crude oil is flashes at a

pressure below than the atmospheric usually less than 1 atmospheric

pressure and at a temperature where gas oil usually not fractionate and

also the bottom residue will not suffer nay thermal decomposition.


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The maximum performance or ability to lift the gas oil depends on the

lowest absolute pressure that can be maintained in flash zone with

maximum non cracking temperature. The optimum temperature of flash

zone is 399 oC.

Vacuum column operates on the principle that boiling point of any

material is lowered as the pressure id reduced.

Vacuum residue must be handled very carefully that most of the refinery

products, the vacuum bottom pump which handle very hot liquid can lose

its suction. It can be minimized by introducing some cooled vacuum

bottom to the column bottom and can reduce the tendency to form

vapor. This problem can also be minimized that vacuum bottom pump’s

gland should be tightly close so that air cannot be introduce into pump.

The vapor rising from the flash zone of is the gas oil product and no

further fractionating is required. All we just need now is to condense

these vapors as efficiently as possible. This can be done in tube and shell

condensers but these are inefficient at low pressures and a high pressure

drop through this condenser will raise the flash zone pressure.

That’s why the most efficient method is to contact the hot vapors with

the cooled liquid in heat exchanger.

In order to reduce the cost of operating the vacuum distillation column

the VDU is combined with CDU so that as much heat as possible is

recovered from the hot product streams by heat exchanging with the cold

crude streams.

The vacuum gas oils are then routed to Dieselmax unit and the vacuum

residue is then forward to the Visbreaker unit.

The block diagram of the vacuum distillation unit is as given,

The products if the vacuum distillation unit is


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Light vacuum gas oil ( LVGO )

Heavy vacuum gas oil ( HVGO )

Vacuum residue

M S

W A S T E G A S

T O 1 0 0 - H 1

S t r i p p i n g S t e a m

H S

L S

T W S

1 1 0 - E A 4

T W R

1 1 0 - E 2

9 4 5 - E 7 2

8 4 - E 1 2

F u e l O i l T a n k s

F u e l O

i l

C W S

C W R

L S L

S o u r W a t e r

m 3 / h

1 1 0 - E A 1

1 1 0 - E A 3

1 1 0 - V 1

1 1 0 - V 1

1 1 0 - H

1

1 1 0 - H 1

M E 1 - J 1 A / B

M E 1 - J 3 A / B

M E 1 - J 2 A / B

M E 1 - E 3

M E 1 - E 2

M E 1 - E 1

F O B

V G O T A N K

F O B D O B

L D O

V G O T K

D M A X

L V G O

H V G O

S l o p W a x

V a c u u m B o t t o m

V B U

F O B

R F O

1 0 0 - E 1 9 - 1 7

1 1 0 - E 2

1 1 0 - E 1

1 0 0 - E 1 8 -

1 5 - 1 3 - 1 1

C R U D E

C R U D E

F E E D

R e d u c e d C r u d e

1 1 0 V 6

1 1 0 V 6

1 1 0 - V 7

1 1 0 - V 7

1 1 0 - V 2

1 1 0 - V 2

1 1 0 V 3

1 1 0 V 3

1 1 0 - V 4

1 1 0 - V 4

1 1

0 - P 4

1 1 0

- P 3

1 1 0 - P 2

1 1 0 - P 1

1 1 0 - P 7

V A C U U M D

I S T I L L A T I O N

U N I T

V A C U U M D

I S T I L L A T I O N

U N I T


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V isbreaker unit:

The Visbreaker Process Unit is designed to process 15,560 BPSD of vacuum

residue from the Vacuum Distillation Unit, based on the Crude and Vacuum

Distillation Units processing 100% Arabian Light crude oil and 70/30 volume

percent blend of Upper Zakum/Murban crude oils.

The feed of the Visbreaker unit is,

Vacuum residue

The visbreaking unit is the combination fuel gas and fuel oil fired In the presence of

heat the bottoms are broken to give off gases, naphtha and vacuum bottoms.

Heating the material to predetermined heater outlet temperatures and rapid

quenching of furnace outlets facilitates thermal cracking and altered viscosity

necessary for further processing.

This unit consists of three heaters for heating purpose. For safety purpose the

sour water from this section is forward to the amine treating unit.

The products of the visbreaking unit are,

Off gases

Unstabilized naphtha Visbreaker bottom residue

The block diagram of Visbreaking unit is,


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G as concentration unit:-

The Gas Concentration Process Unit is designed to recover C3/C4 LPG and to

produce a stabilized naphtha feed to the Naphtha Hydro treating Unit. Gases

from various process units will be compressed and routed through an

absorption system to maximize the recovery of LPG.

The feeds of the gas concentration unit are,

Feed gases to the Gas Concentration Process Unit are as follows:

• Gas from the Net Gas Compressor at the Crude Distillation Unit in case of

Upper Zakum and Murban blend oil feed.

• Gas from the Fractionator Receiver at the Visbreaking Unit.

• Gas from the Stripper Receiver at the Diesel max Unit.

• Gas from the Flash Fractionator Receiver at the Diesel max Unit.

• Gas from the Stripper at the Naphtha Hydro treating Unit.

The liquid feeds to the Gas Concentration Process Unit are as follows:


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• Unstabilized naphtha from the Crude Distillation Unit.

Unstabilized naphtha from the Fractionator Receiver at the Visbreaking

Unit.

Unstabilized naphtha from the Product Fractionator Receiver at theDieselmax Unit.

Unstabilized naphtha from the Flash Fractionator Receiver at the

Dieselmax Unit.

Unstabilized liquid from the Stripper Receiver at the Naphtha Hydro

treating Unit.

The operation of gas concentration unit consist of the following three major

sections

Compressor section

Absorption section

Distillation section

In the compressor section the gas is pressurize for further use in other two

sections. All incoming gas streams except for the Naphtha Hydro treater

Stripper gas combine and flow into a two stage centrifugal compressor via the

compressor suction cooler and the compressor suction drum. Mists separated

and accumulated in the compressor suction drum is manually drained out and

sent to the CDU.

Gas from the Naphtha Hydrotreater Stripper combines with the first stage

discharge which is pressurized from 3.7 kg/cm2G to 8.2 kg/cm2G, and enters the

second stage of the compressor via the inter stage cooler and the compressor

inter stage suction drum

Gas pressurized to 17.1 kg/cm2G mixes with the Stripper overhead vapor, the

incoming liquid stream, and Primary Absorber bottoms. The combined stream is

cooled in the high pressure cooler and sent to the high pressure receiver Liquid

separated and accumulated in the compressor inter stage suction drum is sent

to the combined stream by the compressor inter stage suction drum pumps.


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The absorption process consists of passing a cooled liquid of heavier

components downwards through a column while a gas of lighter components

travels upwards through the same column. During this process the heaviercomponents of the gas are recovered from the gas by absorption. The degree of

absorption is controlled by the ratio of liquid flow to gas flow, the degree of

contact time between the two flows, and the temperature of the heavier liquid

flow.

The first column in the absorption process is the primary absorber. In the

primary absorber, the liquid flow, which is stabilized naphtha coming from the

debutanizer, enters the column above the first tray. The C3/C4 rich gas stream

from the high pressure receiver enters the column below the bottom tray. The

degree of absorption in this column is partly controlled by a reflux stream near

the middle of the column. This intercooler stream is withdrawn from the draw

tray No. 16 in the middle of the column and passes through a cooler before

returning to the column just above the draw tray on flow control. The

intercooler reflux is returned to the column at approximately the same

temperature as the stabilized naphtha entering the top of the column. This

cooling is necessary due to the increase of temperature of the absorbing liquid

caused by the heat of absorption. This cooling of the liquid stream allows for

better recovery of the C3/C4 material. The primary absorber rich oil from thebottom of the column returns to the high pressure receiver, where most of the

light material recovered is pumped with the heavier material to the stripper for

further processing. The operation of the stripper will be discussed in the

distillation process section.

The second column in this process is the sponge absorber. This column is smaller

in size and filled with packing that allows intimate contact between the liquid

and gas streams. The overhead of the primary absorber is directed to the

bottom of the sponge absorber, while the circulating diesel enters the top of the

column.

The process principal of the sponge absorber is the same as the primary

absorber, in that the overhead gas from the primary absorber is intimately

contacted with a heavier liquid to recover the C3/C4 material that was not


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absorbed in the primary absorber. The main differences between the primary

and the sponge absorber are the internals of the column, and the type of lean

Oil used. Instead of trays like those used in the primary absorber, the sponge

absorber has a packed section to cause the intimate contact between the down

flowing liquid and the upward flowing gas. The sponge absorber does not have a

reflux flow as the primary absorber does, but the sponge absorber has a

demister blanket installed near the top of the column to aid in the removal of

liquid from the gas leaving the top of the column. The lean oil used in the

sponge absorber is circulating diesel from the Crude Unit. After passing down

the column, the diesel is collected in the bottom of the column where it is

returned to the Crude Unit as rich oil on level control at the bottom of the

sponge absorber. Pressure control for the absorption section is placed on the

lean gas exiting the top of the sponge absorber. The lean gas after passing

through the pressure control valve is directed to the Amine Treating Process

Unit and then to the refinery fuel gas system. And the pressure control valve

maintains a constant pressure on the entire absorption system.

Liquid hydrocarbon from the high pressure receiver is pumped to the stripper

where hydrogen sulfide (H2S), ethane and lighter components are stripped out.Feed to the stripper is heated using the total debutanizer bottoms stream in the

stripper feed exchanger. Stripper charge enters the column above the top tray.

Stripping action is provided via reboilers at the bottom of the column through

which heat is supplied from the debutanizer bottoms stream and MP steam. The

steam flows through the tube side of the stripper reboilers with its condensate

flow regulated by a flow controller which is reset by the stripper overhead

vapor rate. The overhead vapor is returned to the high pressure cooler. Bottoms

material is pressured to the debutanizer on level control.

The feed to the debutanizer is the stripper bottoms stream. Heat is supplied via

a reboiler. The heating oil to the reboiler is the circulating diesel from the Crude

Unit. The diesel is regulated by a flow recording controller. The total flow of


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debutanizer bottoms is directed to one of the stripper reboilers and to the

stripper feed exchanger. After exiting the stripper feed exchanger, the

debutanizer bottoms flow is divided into two flows. The first flow is directed on

Flow control to the primary absorber as lean oil or sent to the stabilizednaphtha storage tank. The second flow or net production of stabilized naphtha

is pumped on level control to the Naphtha Hydro treating Unit.

Overhead vapors (butane, propane and propylene) are condensed by an air

cooler condenser then collected in the debutanizer receiver a portion of the

total overhead is pumped back to the column as reflux. The quantity of reflux is

regulated by a flow recording controller which is reset by the level indicator

controller on the receiver. The net overhead liquid product is pumped out on

flow control which is reset by the Tray 10 temperature indicator controller. The

debutanizer overhead product is pumped to the LPG Merox Unit for sulfur

removal.

The debutanizer column pressure is controlled by a pressure recording

controller on the overhead vapor line which controls the amount of vapor

directed through the condenser. The pressure differential controller regulates a

valve in a bypass line around the cooler. This allows a small amount of vapor to

bypass the condensing system to regulate the surface area available to

condense the overhead vapor, hence regulating the rate at which the vapor is

removed from the column.

The products of the gas concentration unit are,

LPG

Stabilized naphtha

Off gases

The block diagram of the unit is as,


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N ephta Hydro TreatingUnit:-

The unit has the processing capability of 25,400 BPSD. This is a catalytic refining

process and uses a catalyst and hydrogen stream to decompose the organic

sulfur, oxygen and nitro compounds.

The feed of the Nephta hydro treating unit is,

Naphtha from hydro treating and Dieselmax unit in combine form

Makeup ammonia from the Plat forming unit

The unit has major three sections.

Reactor section

Stripping section

Splitter section

The purpose of the reactor section is to remove the naphtha fractions so that it

can be used in the plat forming unit for the further processing. There are six

types of reactions which occur in the reactor section of Nephta hydro treating

unit.

Reactions:

Conversion of organic sulfur compounds to hydrogen sulfide

Conversion of organic nitrogen compounds to ammonia


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Conversion of organic oxygen compounds to water

Saturation of olefins

Conversion of organic halides to hydrogen halides

Removal of organo-metallic compounds

The feed from the Gas concentration unit or from the stabilizer naphtha tanks is

send to the feed surge drums. Tanks must be gas blanketed so that they can

prevent the oxygen from stabilized naphtha.

Even trace amount of olefins can cause the polymerization of olefin and when

stored for long times it can cause fouling and loss of heat in transfer efficiency.

From feed surge drum the naphtha feed is pumped and combined with

hydrogen rich stream from the recycle compressor.

The feed combines at a point and enters in combined feed exchangers where

the feed is heated and effluent from reactor 2 is cooled.

The combined feed leaving the exchanger is all vapor and this combined feed

leaving the exchanger is heated through the shall side of the reactor no 1

effluent cooler and flow to charge in the heater where it is heated to required

temperature.

And then combined feed enters in the reactor no 1 which is design for down

flow operation and contain sufficient amount of catalyst to remove

contaminants. The reactor no 1 removes the sulfur and saturate olefins while

the second reactor hydrogenates any recombinant sulfur formed in the reactor

no 1.

The effluent from reactor no 1 is cooled in effluent cooler and then enter in to

the second reactor flows through heat exchangers and then into the product

condenser.

A water wash injection points are provided in the reactor so that any salt build

up in the pipes, exchangers can be removed.


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Then this effluent passes through the product trim condenser at a low enough

temperature to ensure the complete recovery of naphtha and enters to product

separator to ensure complete separation of gas, hydro carbon, liquid and water.

It is also provided with a water boot to collect the water injected for saltremoval then the water is automatically pressured to the water stripper at

amine treating unit.

The rich hydrogen gas is provided to the reactors by the recycle compressor.

This takes suction from the top of separator with the discharge combining with

the naphtha feed upstream of heat exchangers.

Recycle compressor suction drum is provided between the separator and

compressor to remove any condensed liquid in the recycle gas, protecting

compressor from damage

Since the process consumes hydrogen, so a hydrogen rich gas stream is brought

into the unit to make immediately upstream of heat exchanger.

The liquid hydrocarbon is the sent to the splitter bottom exchanger and the

Stripper Feed-Bottoms Exchanger, and thus heated material enters the Stripper,

Stripper Reboiler is provided to supply the required heat input for stripping

hydrogen sulfide, water, light hydrocarbons and dissolved hydrogen from the

feed and vapor from 200v2, passes overhead to the Stripper Condenser, and

Stripper Trim Condenser,, and to the Stripper Receiver. Normally, no netoverhead liquid product is produced, and all of the liquid in the receiver is

pumped back to the stripper as reflux. A reflux/feed ratio of approximately

0.25 is sufficient to strip the light ends and water from the tower. The reflux is

pumped into the stripper on receiver, to increase the amount of reflux; the

reboiler heat input must be increased to provide more overhead material. The

net overhead gas leaves the receiver to Gas Concentration Unit or to flare via

with split range control. Stripper receiver pressure is maintained at 9.4

kg/cm2g.

The stripper overhead system is equipped with inhibitor addition facilities to

prevent corrosion of the process lines and equipment by hydrogen sulfide in the

overhead vapor. The corrosion inhibitor is pumped directly from a drum,


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diluted with a small slipstream of reflux, and injected directly into the overhead

vapor line at the top of the stripper.

The stripper bottoms material is pumped through heat exchangers and is sent to

the Splitter.

The splitter is design to split C5 and C6 components. The light naphtha product

is mostly a C5 fraction and heavy naphtha is C6 fraction.

The splitter feed is cooled by the stripper feed material in the splitter feed

exchangers. Splitter boiler is provided to fulfill the heat requirement for the

column.

The overhead vapor is condensed in the splitter trim cooler and liquid collects in

the splitter receiver.The light naphtha from the top of splitter is cascaded with a temperature

controller at the top tray of splitter

Products:

The light naphtha is sent to tankage and for blending system while the heavy

naphtha from the bottom of splitter is dent to heat exchanger via pump and

then send to the plat forming unit.

The block diagram of the unit is


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LPG-Merox unit:-This unit has capability of processing 4500 BPSD of Lpg to achieve a sweet

product with less than 5 wppm mercaptan and less than 20 wppm of total

sulfur.

The feed of the LPG Merox unit is C3/C4 from debutanizer receiver at gas

concentration unit.

This unit consists of three major sections.

Pretreatment section Extraction section

Caustic regeneration section

The LPG from the gas concentration unit is fed at bottom tray no 10 of amine

absorber for counter current liquid- liquid contacting with a 20% (DEA) solution

from amine treating unit and the lean amine from tray no 1 and at top enters

and goes downward and contacted with the Lpg coming from bottom

Lean amine become rich and removes from the bottom of the absorber and is

returned to the amine treating unit. The LPG is then advanced to prewash vessel

where it is contacted with 10 degree Baume caustic for the removal of residual

hydrogen sulfide. LPG for caustic wash is then sent to the filters for extraction

section. Whereas the spent caustic is sent to effluent treatment plant via spent

caustic degassing drums.

LPG from prewash vessel is send to the bottom of extractor. Lean caustic via

pump is fed at top of extractor. The counter current fashion takes place. The

rich caustic is removed from the bottom of extractor and returned to causticknockout drum to separate caustic from hydrocarbons stream.

Then LPG is send to the sand filters which will coalesce and remove any

entrained caustic.


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The mercaptan rich caustic from extractor bottom and air injected is introduced

in oxidizer where it is heated to initiate the mercaptide oxidation reaction. From

the oxidizer the mixture enters into the disulfide separator where spend air is

removed from disulfide separator. It leaves from the top of separator and is

mixed with the fuel gas then it is send to the Sulfur recovery incinerator.

The disulfide oil is pumped to the tankage and blending system for blending

with fuel and oil gasoline.



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K ero-Merox unit:-The processing capability of the Kerosene Merox Process Unit is 20,000 BPSD of

kerosene to achieve a jet fuel product with less than 10 wppm mercaptan and

less than 1 wppm sodium.

The feed of the section is kerosene.

This unit consists on major three sections.

Pretreatment section

Sweetening action

Post treatment section

The purpose of pretreatment section is to remove naphthenic acid from feed is

that if these are not removed then sodium naphthenates are formed insweetening reactor which is surfactant and coat the catalyst and block the pores

of charcoal catalyst support. This is achieved by alkaline electrostatic prewash.

Mercaptans are directly converted to disulfides in fixed bed reactor system

which remains in product and there is no reduction in sulfur contents because

the vapors of disulfides are so low reactant to mercaptan so there presence is

much less objective.

Raw crude from CDU is routed directly to electrostatic coalesce prewash atpressure 8.4kg/cm2 and at a temp of 40 Degree. The feed kerosene before

entering to prewash electrostatic coalescer is mixed with 3 degree Baume

caustic solution by means of mixing device and pumped by caustic injection

pump from caustic storage tank.


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Naphthenic acid in kerosene stream is neutralized by the caustic and the spent

caustic is settled in the electrostatic coalescer. The reaction takes place is

RCOOH + NaOH → RCOONA + H2O

Then air is compressed by reciprocating compressor and is mixed with kerosene

discharged from electrostatic coalescer. A small amount of catalyst is activator

is injected into the kerosene stream after the addition of air. The combined

stream passes through a bed of Merox catalyst in the reactor flows where the

mercaptans are oxidized into disulfides.

The sweetened kerosene from the reactor flows into the caustic settler for

gravity separation of entrained.

The treated kerosene from caustic settler into the water wash vessel to remove

entrained caustic solution and water soluble surfactants.

Wash water when required is injected by was water pump at the bottom of

water wash vessel. The waste water is drawn from the bottom of wash water

vessel.

The washed kerosene is then introduced into the salt filter and then last step is

clay filter which serves basically as a final clean-up step to assure a kerosene

product that is free of solids, color bodies, water and soaps.

The Salt Filter immediately ahead of the Clay Filter protects the clay from being

rendered ineffective prematurely by free water.

The treated kerosene product is run down to Tankage and Blending System at apressure of 3.52 Kg/cm2G and at a temperature of 40 under pressure control.



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S torage tanks:-Storage tanks are containers that hold liquids used for short or long term

storage. Storage tanks containing organic liquids, in-organic liquids and can be

found in many industries.

Industries where storage tanks can be found are petroleum producing andrefining, petrochemical and chemical manufacturing and other industries.

Storage tanks are available in many shapes and having different types.


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Fixed roof tanks are common in production facilities to store hydrocarbons with

vapor pressure close to the atmospheric pressure. Before using it should be

equipped with pressure vacuum valves and purge with natural gas to eliminate

air intake into the vapor space. Product evaporate loses can be high especiallywhen crude is added to tank and vapors are expelled through the pressure vent

valve.

Floating roof tanks:-

The floating roof tank has further categorized into,

External floating roof tank Internal floating roof tank

Dome external floating roof tank

External Floating Roof Tank:-

A typical external floating roof tank consists of an open-topped cylindrical steel

shell equipped with a roof that floats on the surface of the stored liquid, rising

and falling with the liquid level. The floating roof is comprised of a deck, fittings,

and rim seal system. Floating roof decks are constructed of welded steel plates

and are of three general types: pan, pontoon, and double deck.

Although numerous pan-type decks are currently in use, the present trend is

toward pontoon and double-deck type floating roofs.

Manufacturers supply various versions of these basic types of floating decks,

which are tailored to emphasize particular features, such as full liquid contact,

load-carrying capacity, roof stability, or pontoon arrangement. The liquid

surface is covered by the floating deck, except in the small annular space

between the deck and the shell; the deck may contact the liquid or float directly

above the surface on pontoons.


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External floating roof tanks are equipped with a rim seal system, which is

attached to the roof perimeter and contacts the tank wall. The rim seal system

slides against the tank wall as the roof is raised and lowered. The floating deck

is also equipped with fittings that penetrate the deck and serve operationalfunctions. The external floating roof design is such that evaporative losses from

the stored liquid are limited to losses from the rim seal system and deck fittings

(standing storage loss) and any exposed liquid on the tank walls (withdrawal

loss).

Internal Floating Roof Tank:-

That tank has both, a permanent fixed roof and a floating roof inside. There are

two basic types of internal floating roof tanks:

Tanks in which the fixed roof is supported by vertical columns within the tank

tanks with a self-supporting fixed roof and no internal support columns

The fixed roof is not necessarily free of openings but does span the entire open

plan area of the vessel. Fixed roof tanks that have been retrofitted to employ an

internal floating roof are typically of the first type, while external floating roof

tanks that have been converted to an internal floating roof tank typically have aself-supporting roof.

Tanks initially constructed with both a fixed roof and an internal floating roof

may be of either type. An internal floating roof tank has both a permanently

affixed roof and a roof that floats inside the tank on the liquid surface (contact

deck) or is supported on pontoons several inches above the liquid surface

(noncontact deck). The internal floating roof rises and falls with the liquid level.

Domed External Floating Roof Tank:-

Domed external floating roof tanks have the heavier type of deck used in

external floating roof tanks as well as a fixed roof at the top of the shell like


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internal floating roof tanks. Domed external floating roof tanks usually result

from retrofitting an external floating roof tank with a fixed roof.

As with the internal floating roof tanks, the function of the fixed roof is not to

act as a vapor barrier, but to block the wind. The type of fixed roof most

commonly used is a self-supporting aluminum dome roof, which is of bolted

construction. Like the internal floating roof tanks, these tanks are freely vented

by circulation vents at the top of the fixed roof. The deck fittings and rim seals,

however, are basically identical to those on external floating roof tanks.

T he Parco (MCR) storagetanks:-

Unit 945:-

Tank# Service Capacity (m3)

Tk 945: Crude tanks 44169


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1,2,34,5,6

Tk945: 9,10,11 HOBC product 2390

Tk945: 12,13,14 Regular gasoline 5650

Tk945: 15,16,17 JP-1 product 7130

Tk945: 18,19,20 JP-8 product 2010

Tk945: 22,23

24

Kerosene product 7940

19860

Tk945: 21,

25,26

Diesel product 19860

25420

Tk945: 27,28,29 Fuel oil product 12760

Tk945: 30,31,32 LPG product 1530

Tk945: 33,34 Heavy naphtha 5770


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tanks

Tk945: 35 VGO intermediate 29730

Tk945: 37,38 Light naphtha tank 1630

Tk945: 30,40 Reformate tank 5670

Tk945: 46 Stabilized naphtha 12927

Tk945: 52,53 Stabilized naphtha 17457


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A ssignments


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Assignment no 1:-

Bottom up gradation technologies:-

With the continuous depletion in world oil reserves and increasing demand of

petroleum products, the refiners are forced to process more and heavier crude

the cost advantage of heavy crudes over light crudes has incentivized many

Refineries to process heavier crude, therefore increasing the heavy residue

produced at a time when fuel oil demand is declining. In order to dovetail both

the requirement for processing crude oil of deteriorating quality and enhancing

distillates of improved quality, technological up gradation have been carried out

at refineries which takes care of processing heavy crudes as well as maximizing

value added products and stringent product quality requirements.

Technologies:-

There are two types of up gradation technologies,

Thermal cracking technology Catalytic cracking technology

Cracking:-


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Cracking of heavy residue is most commonly used method for up gradation of

residues. This involves of decomposition of heavy residues by exposure to

extreme temperatures in the presence or absence of catalysts.

Thermal cracking:-

Cracking at elevated temperatures in the absence of catalyst eg: Visbreaking

delayed coking, Fluid coking etc.

Catalytic cracking:-

Cracking in presence of catalyst e.g.: FCC, Hydrocracking, and DCC

Thermal cracking technology:-

Thermal cracking process for up gradation of heavy residue has been used since

long and still it is playing an important role in the modern refinery through up

gradation of heavy residue and improving the economics of the refinery through

the production of lighter distillate and other valuable product like low value fuel

gas and petroleum coke.

Thermal cracking processes and technologies:-

Visbreaking Delayed coking

Fluid coking

Flexi coking


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Visbreaking:

Visbreaking is essentially a mild thermal cracking operation at mild conditions

where in long chain molecules in heavy feed stocks are broken into short

molecules thereby leading to a viscosity reduction of feedstock. A given

conversion in Visbreaker can b

cracking: Soaker visbreaking.

The process conditions are,

Mild thermal cracking (low severity)

Mild (470-500oC) heating at 50-200 psig

Improve the viscosity of fuel oil

Low conversion (10%) to 4300F

Residence time1-3 min

Heated coil or drum

Delayed coking:-

Delayed coking process is used to crack heavy oils into more valuable light liquid products with less valuable gas and solid coke as byproducts. Typical delayed

coking consists of a furnace to preheat the feed, coking drum where the

fractionation of the product takes place. The process conditions are,

Operates in semi batch mode

Moderate (900-960oF) heating at 90 psig

Soak drums (845-900oF) coke walls

Coked until drum solid

Coke (removed hydraulically) 20-40% on feed, Yield 4300F, 30%

Fluid Coking:-


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Fluid coking is non- catalytic fluid bed process where residue is coked by

spraying into a fluidized bed of hot, fine coke particles. Higher temperature with

shorter contact time than delayed coking results in increased light and medium

hydrocarbons with less cake generation. Shorter residence time can yield higherquantities of liquid less coke, but the product has lower value. The process

conditions are,

Server (510-520oC) heating at 10 psig

Oil contact refractory coke Bed fluidized with steam-even heating,

Higher yield of light ends (


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Assignment no 2

What is the advantage of diesel-max unit?

The diesel-max unit is used to maximize the production of diesel. The Dieselmax

Process Unit Catalytically desulfurizes and denitrifies vacuum gas oil (VGO)

feedstock and converts the feedstock to a diesel product, Kerosene, naphtha,

and light ends including LPG in the presence of hydrogen the hydrogen gas

which is used as feed in the diesel maxis used for saturation and removes

oxygenates and other metallic compounds.

Our requirements are achieved we get overhead gases which is used in further

units and distillate is pure diesel which is used as blending component for fuel oil

and also send to storage.

What types of crudes are being used in the

Parco MCR?

There are five types of crude are being used in the refinery. They are as follow.

Arabian light 51%

Upper zakum 17%

Murban crude 17%

Local crude 7%

Condensate crude 7%


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Assignment no 3

Hydrogen cycle of refinery:-

The hydrogen gas is producing in the plat forming unit 300 and then routed to

the net gas three stage compressors where its pressure is increased from 3.1

kg/cm2 to 95.6 kg/cm2.Then it is routed to the chloride treater where hydrogen chloride is removed

which can cause catalyst efficiency.

The production rate of hydrogen in plat forming unit is 29000 Nm3/hr.

The hydrogen gas is very important in refinery; the hydrogen gas used is due to

that it removes impurities or gases from crude.

Hydrogen gas is used to remove

Sulfur as hydrogen sulfide Nitrogen as ammonia

Oxygen as water

Metals

Olefins and metal halides

Consumption:-

The hydrogen gas consumption in the following units as follow,


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Naphtha hydro treating unit ( 20Nm3/m3)

Diesel-max unit (126NM3/m3)

DHDS unit (30-35Nm3/m3)

Fuel gas system unit

Assignment no 4:-

Blending components for the followings:-

1.

Mogas:-

The Mogas is produced by blending the following,

Light naphtha RON 73

Heavy naphtha RON 44

Reformate RON 98

The research octane number of gasoline is 87.7.therefore we mix the abovecomponents in the following percentage

Light naphtha30%

Heavy naphtha 8%

Reformate 62%

And gasoline is made then it is send to the market.

2. Diesel:-

The blending components of diesel is as follow,


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Diesel-max residue

DHDS diesel

Straight run diesel oil

Furnace oil:-

The blending components of furnace oil are as follow,

Visbreaker bottom residue 70%

Diesel max residue 30%

The viscosity of Visbreaker bottom residue is 1500 CST while diesel max bottomresidue has 35 CST. We mix these in proper ratio and get furnace oil. If by mixing

they do not meet the requirements then we mix it with

LVGO

Straight run gas oil

Kerosene


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B ibliography:• Operating manual by JGC corporation for Pak

Arab refinery Ltd. Mid country refinery

project, Mahmood Kot, Pakistan

• Refinery training manual, vol.1,2,3,4,5 Pak-

Arab refinery Ltd, Mid country refinery

project, Mahmood Kot, Pakistan, Shazoo Islam

printers Multan, Pakistan

• WWW.weikipedia.com

internship report giki

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