MINISTRY OF EDUCATION AND TRAINING
HANOI UNIVERSITY OF MINING AND GEOLOGY
----------

Graduation Thesis
Nguyen Quang Trung
CTTT12210127

Thesis:
Studying about Control System of
DCU - Dung Quat Refinery

Ha Noi, 6 - 2017


MINISTRY OF EDUCATION AND TRAINING
HANOI UNIVERSITY OF MINING AND GEOLOGY
----------

Graduation Thesis
Nguyen Quang Trung
CTTT12210127

Thesis:
Studying about Control System of
DCU - Dung Quat Refinery

SUPERVISOR:

REVIEWER:

Ha Noi, 6-2017


Control System of CDU Dung Quat Refinery

INTRODUCTION
Phân xưởng chưng cất khí quyển (Crude Distillation Unit) là phân xưởng cửa
ngõ của nhà máy lọc hóa dầu Dung Quất, là phân xưởng cung cấp nguồn nguyên
liệu cho hầu hết các phân xưởng kế tiếp của nhà máy lọc dầu. Do đó, kiến thức về
phân xưởng này là vô cùng quan trọng cho bất cứ 1 kỹ sư công nghệ hóa dầu nào.
Sự chưng cất được tiến hành trong các thiết bị chưng cất gồm tháp chưng cất và
các thiết bị phụ trợ khác như lò gia nhiệt, thiết bị tách muối… Hầu hết các tháp
chưng cất dùng trong công nghệ lọc dầu và chế biến khí tự nhiên là tháp đĩa, và
tháp chưng cất của chính của nhà máy lọc dầu dung quất cũng vậy. Trong một tháp
chưng cất luôn có nhiều đĩa, tương ứng với mỗi dải nhiệt độ khác nhau lại cho ra
những sản phẩm khác nhau phục vụ cho các phân xưởng phụ trợ kế tiếp. Vì vậy
việc điều khiển nhiệt độ đầu ra cũng như đầu vào của các dòng sản phẩm là việc
làm vô cùng quan trọng. Nó ảnh hưởng trực tiếp đến chất lượng sản phẩm thương
mại và ảnh hưởng gián tiếp đến chi phí vận hành của nhà máy.
Do đó, trong đồ án tốt nghiệp: “Control system of CDU Dung Quat”, em xin
được tìm hiểu về các quy trình điều khiển đặc trưng của tháp chưng cất dầu thô Nhà máy lọc hóa dầu Dung Quất.

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Control System of CDU Dung Quat Refinery

PREFACE

I sincerely thank Dr. Nguyen Van Toan who has dedicated
guidance and help me. Thanks to the teacher's guidance, I
understood the necessary issues and completed this thesis in
due time.
However, with the large of workload and in a limited time, so
during the process of compeleted this thesis I can not avoid
mistakes and shortcomings. I hope all of our beloved teachers
would review and help me perfect my project.
Once again, I would like to express my deep gratitude to Dr.
Nguyen Van Toan and all the teachers of Oil and Gas Faculty major in Oil refining and Petrochemistry -( Hanoi University of
Mining and Geology ) have helped me during 5 years of
studying and finishing this thesis.
Thank you sincerely!

Hanoi, 6-2017
Student
Nguyen Quang
Trung

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Control System of CDU Dung Quat Refinery
LIST OF Figures
Figure 1.1: Geographical of Dung Quat Refinery in the map...............................
Figure 1.2: Organization Chart of Binh Son refinery and Petrochemical Plant.....
Figure 1.3: Organization Chart of BSR.................................................................
Figure 1.4: Table of Dung Quat Refinery’s Process Unit....................................

Figure 2.1: Crude Distillation Unit (Unit 011) of Dung Quat Refinery
Figure 2.2: 3D strucuture of Crude Distillation Unit from South East..................
Figure 2.3: 3D sstrucuture of Crude Distillation Unit from West East.................
Figure 3.0: The P&ID diagram for the crude oil distillate control system
Figure 3.1: Simple model of Kerosene thermal process...................................
Figure 3.2: The P&ID diagram of Kerosene thermal control process..............
Figure 3.3: Block diameter for the Kerosene thermal control process...............
Figure 3.4: Simple model of Over-head product line thermal process............
Figure 3.5: The P&ID diagram of Over-head product thermal control process..
Figure 3.6: ck diameter for Over-head product thermal control process.......
Figure 3.7: Simple model of Bottom product line control process..................
Figure 3.8: Block diameter for Over-head product thermal control process.......

LIST OF Tables
Table 1.1 The main Process units and Offsites of Dung Quat Refinery .........
Table 1.2 Product’s Capacity........................................................................
Table 2.1: Distillation Curve and Propotion Curve of Bach Ho Crude oil.........
Table 2.2: Distillation Curve and Propotion Curve of Dubai Crude oil.........
Table 2.3 Product Standards...............................................................
Talble 2.4 Summary of heat exchangers as well as hot product lines.........

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Control System of CDU Dung Quat Refinery

TABLE OF CONTENTS


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Control System of CDU Dung Quat Refinery

Chapter 1 - An overview of Dung Quat Refinery

1.1 Geographical location of Dung Quat Refinery
Dung Quat or Binh Son oil refinery, the first oil refinery of Vietnam is located at Dung
Quat Economic Zone, Quang Ngai province.
Which has the Northwest borders Chu Lai Airport, the West borders National Highway
1A, East and Northeastern East border the East Sea. And Quang Ngai city is at the
Southwest. Distance from Dung Quat refinery to:
- To Quang Ngai city: 25-40 km
- To Da Nang city: 100 km
- To Hanoi: 880 km
- To Ho Chi Minh City: 870 km
- 13 km to Chu Lai airport
- Inland Maritime road: 30 km
- International Maritime road: 190 km
- Geographical coordinates: 1080.47 degrees East, 150.23 degrees North latitude.

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Control System of CDU Dung Quat Refinery


Figure 1.1 Geographical of Dung Quat Refinery in the map
1.2 Natural Conditions:

•

Topographic:
- Dung Quat Economic Zone or Binh Son Refining is located in the flat terrain of
Quang Ngai Province, between the coast are low mountain range and sand dunes.
+ Highest altitude : + 20m.
+ Medium altitude: 4 ÷ 10m.
+ Lowest alitude : 0.1 ÷ + 3.0m.
- The terrain has the shape of sloping from West to East and from South to North

with an average slope of 0.4 ÷ 8%.
• Climate:
- Dung Quat Refinery is in the South Central climate region. So it has two
separated season.
+

Winter: Not so cold,the average winter temperature is 19 oC and absolute

minimum temperature does not fall below than 12oC.
+ Summer: Temperature are fairly high in about 4 months which have the average
temperature of 28oC.

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Control System of CDU Dung Quat Refinery
Other elements:
+ Sunshine: Quang Ngai Province has the avarage sunny hours of 1,800 ÷ 2,000
hours per year.
+ Wind: Quang Ngai province has a hot dry West wind in the summer, but not as
powerful as the North Central Region. It has long-lasting hot season, sometimes
accompanied with the strong southwest winds causes drought in the area.
Northeast Monsoon: Often causes gusts, whirlwinds and often causes heavy rain,
while temperatures drop sharply.
+ Average wind speed

: 2.9 m / s.

+ Maximum wind speed : 40m / s.
+ Typhoons: Quang Ngai as well as all the other central region which are sea
coastal provinces are affected by storms. On average per year, storms directly
affects Quang Ngai province, caused heavy rain and very strong winds of level 6
or higher. There are also three to four tornados along with heavy rain and strong
winds, sometimes accompanied by sea level rise.

1.3 The importance of Dung Quat Refinery
Over the years the world has witnessed major fluctuations and needs in the oil and
refined oil markets. Unstable situation in the major oil-supplying regions and the rise in
demand of Oil-supplying have helped the price of Oil and gasoline increased to the
record levels. Especially, In the year 2008, the world crude oil market was constantly
fluctuating unnormally. It was the reason pushing the crude oil price to the record of
150$/barrel, and then fell down magnificently to below 45$/barrel.
Fluctuations in crude oil prices have had a negative impact on many economies, leading
to many consequences, affecting the growth rate of many countries, including our country

Vietnam. To reduce the negative impact of oil price fluctuations and ensure our national
energy security, Vietnam needs to be proactive in satisfying domestic demand of oilsupplying. Building refineries will create a precondition for the chemical industry to

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Control System of CDU Dung Quat Refinery
develop. Refined products are the main raw material for polymerization production,
lubricant additives and some cosmetic products . Nowaday, more than 99% of the oil
exports, 50% of the imported oil products are due to Foreign transport. The production
and consumption of oil in the country make the domestic transporting service increase,
especially the shipbuilding industry grow rapidly. These are two important sectors that
are capable of generating great added value and a lot of potential for development. So
after all, Vietnam has decided to invest in building the first oil refinery in Dung Quat Quang Ngai called Dung Quat The first Oil Refinery . Dung Quat is located in Quang
Ngai province, in central region of Vietnam where has the lowest economic growth in the
country. The refinery plant located here do not directly create jobs or contribute to local
budgets. But with the development of infrastructure including deep-water ports, roads,
electricity, telecommunication networks ... serving refineries (without those factories)
Open policies will attract domestic and foreign investment projects in Dung Quat
economic zone in particular and in the central region. Dung Quat has attractive
comparative advantages: located in the midst of Vietnam and the region; There is Chu Lai
International Airport, deep sea port; Has a new city with a full range of high quality
amenities and services; To enjoy the highest privileges in Vietnam and to apply the
regime and mechanism of open management in line with international practices and
adaptation to the nature of economic globalization today.

1.4 Technical Features
Dung Quat refinery has a designed capacity of 6.5 million tons of crude oil annually, or

140 thousand barrels per day (22×103 m3/d). The capacity would be expanded to
10 million tons per year by 2013–2014. In addition to fuels, the refinery will also produce
petro-chemical products. The refinery complex area comprises:
•

Overall Refinery Process, Utility and Offsites Facilities: about 110 ha;

•

Crude Tank Farm and Flare Area: about 42 ha;

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Control System of CDU Dung Quat Refinery
•

Product Tank Farm: about 36 ha;

•

Seawater intake, Waste Water and Crude Oil Pipelines: about 4 ha;

•

Interconnecting Pipelines, road and right of Way: about 40 ha;

•


Product Harbor Service Area: about 135 ha.

Main contractors of the refinery were Technip, JGC Corporation, and Técnicas
Reunidas. The refinery cost US$3 billion, up from $2.5 billion previously and more than
double an original cost estimate of about $1.4 billion in 1994. It may need another
$1 billion to build a desulphurising unit targeted for 2013.

1.5 History of Dung Quat Refinery
The Dung Quat refinery story began in 1995 with the withdrawal of Total from the
project (Total claimed the site of the refinery made no sense and would involve increased
costs of more than $500m).
A consortium of foreign firms stepped in (LG Group, Petronas, Conoco, Stone and
Webster and PRC - Chinese Petroleum Company and China Development) but withdrew
two years later for the same reasons.
In 1999, Prime Minister Phan Van Khai took steps to speed up construction of the
country's first oil refinery. The rekindled project was a joint venture between Vietsovpetro
(a Vietnam-Russia joint venture responsible for the bulk of Vietnam's oil exports) and
Russia's External Economic Federation (Zarubeznheft).
The joint venture was dissolved in December 2002 by the Russians who claimed
the refinery was not economically viable at the intended site. In February 2003 Vietnam
decided to go it alone and continue with the refinery construction. Phase I operations
began in February 2009.
The Dung Quat refinery has cost an estimated at $3bn for construction and
equipment. The original front-end engineering and design contractor for the project was

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Control System of CDU Dung Quat Refinery
Foster Wheeler Energy of the UK (this was superseded by a FEED agreement signed
with Technip in 2004). The refinery was built on a site consisting of 338ha of land and
473ha of sea in the Dung Quat Economic Zone.
Vietnam has awarded contracts to a group of construction companies including
Technip-Coflexip of France, JGC Corp of Japan and Technicas Reunidas of Spain, for
technology and equipment supply. Stone and Webster provided project management
consultancy services as per their October 2003 contract.
One of the consortia, TPC Complex, which consists of Technip, Technip
Geoproduction and Technicas Reunidas, was awarded the engineering, procurement and
construction turnkey contracts No.1 and No.4 for the refinery in May 2005. In June 2006
the refinery selected the SmartPlant Enterprise as its standard software for management
of plant design, maintenance and operations of the plant.
The refinery complex area consists of the following components:
- Refinery processing, utility and offsite facilities
(110ha) Crude oil tank farm and gas flare-off area
(42ha)
Product tank farm (36ha)
-Seawater intake, waste water processing and crude oil pipelines
(4ha) Interconnecting pipelines and road access (40ha)
-Harbour product export area (135ha)
Vietnam's National Assembly approved the construction of the Oil Refinery No.1
(Dung Quat) in 1997 with an investment of $1.3 billion (costs have since increased to
$2.5 billion), which came from crude oil revenue, credits and bond sales.
Vietnam reimbursed Russia the $235 million it had put into the VietRoss venture in
December 2002 when Russia withdrew (this money was previously earmarked for
reinvestment into the offshore oil and gas fields of Vietnam).

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The Bank for Foreign Trade of Vietnam (Vietcombank) was able to arrange loans
worth $250 million.
The consortium of contractors that won tender package No.1 was also able to
arrange loans of $500 million in deferred payment terms.
Source of Supply:
The refinery is outfitted to process oil from Bach Ho oil field, which is expected
to run dry before 2020. Petrovietnam has a preliminary agreement with BP for supplies
of similar quality to use exclusively until 2011.
Ownership:
The refinery is owned and operated by Petrovietnam. Petrovietnam negotiates with
foreign oil companies, including Royal Dutch Shell, Essar Group and SK Energy,
toupgrade and sell part of the refinery.
Controversy
Critics of the project claim that the refinery is non-feasible, and the location is
chosen for political, not economical reasons, as most of oil comes from offshore fields in
Southern Vietnam.

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1.6 Organization Chart of Binh Son Refinery and Petrochemical Plant

To run any kind of plants, how the organization chart is will somehow reflect the
effective or the feasibility of the project. Unlike many other companies, BSR has built up
its own organization chart to run their specific refinery configuration

Figure 1.2 : Organization Chart of Binh Son refinery and Petrochemical Plant

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.

Figure 1.3: Organization Chart of BSR
1.7 Raw materials for Dung Quat Refinery
Crude oil used as raw material for the plant is crude oil from Bach Ho field and
imported oil from Dubai.
Bach Ho Oilfield is located in the Southeast Vietnam, about 145km from the coast of
Vung Tau. This is the main oil field for many Refining Factory of VietNam. From
Bach Ho OilField, there is a long-way gas pipeline along the shore to supply Dinh Co
liquefied gas plant, Ba Ria power plant and Phu My electricity center. Nowaday, we
are using the lastest technology for mining, Bach Ho oilfield is currently exploited by
self-spraying technology, contributing to the economy of the country. Crude oil which
extracted from the Bach Ho oilfield has very good quality, which is sweet, light oil
and have the low percentage of impurities. Bach Ho Oilfield has a reserve of about
300 million tons and has been commercially exploited since the middle of 1986. It is
the largest oil field in Vietnam and now has the maximum exploitation capacity. Each
day this oildfield could be exploited about 38000 tons of crude oil accounted for 80%
of Vietnam crude oil output. Accoring to the plan, Dung Quat oil refinery will use



100% of crude oil from Bach Ho field in phase 1 and in phase 2, the factory will
process crude oil mixture (85% crude oil of Bach Ho oildfield and 15% sour oil of
Dubai).
1.8 Process Units:

Figure 1.4: Table of Dung Quat Refinery’s Process Unit

Dung Quat oil refinery is located in Binh Son district, Quang Ngai province. The
project site is comprised of four main areas: technology and auxiliary workshops,


product storage tankage areas, cargo terminals and wharf oil refueling and marine
discharge and discharge systems. These areas are connected by pipeline systems with
adjacent roads.
Total area of the project is approximately 338 hectares, including the following:
- All technology workshops, auxiliaries and peripherals: about 110 hectares
- Sea area: 471 hectares
- Flare and Crude oil storage tank: about 42 hectares
- Product storage tank: about 44 hectares.
-In addition, the port area of the product will occupy about 35 hectares.

Here are the main Process units and Offsites of Dung Quat Refinery (Table 1.1):

Area

Process Unit
Unit 012: Naphtha Hydrotreating Unit (NHT)

Section 1A


Unit 013: Continuous Catalytic Reforming Unit (CCR)
Unit 023: (ISOMER)
Unit 011: Crude Distillation Unit (CDU)

Section 1B

Unit 014: Kerosene Treating Unit (KTU)
Unit 037: – Fuel-gas: Used to burn for heating up for other units.
Unit 015: Residue Fluid Catalytic Cracking (RFCC)
Unit 016: LPG Treating Unit(LTU)

Section 2

Unit 017: RFCC Naphtha Treating Unit (NTU)
Unit 021: Propylene Revovery Unit (PRU)
Unit 018: Sour Water Stripper (SWS)
Unit 019: Amine Regenaration Unit (ARU)
Unit 020: Caustic Neutralization Unit (CNU)

Section 3

Unit 022: Sulfur Recovery Unit (SRU)
Unit 024: (LCO-HDT): diezel Hydrotreating
Unit 058: Effulent Treatment Plant (ETP)


Unit 031: Water for daily using
Unit 033: Cooling water.
Unit 034: Sea water intake for cooling.

Unit 035: Instrument/Plant air
Unit 036: Nitrogent plant
Section
Cold
Utility

Unit 037: Fuel gas
Unit 039: Caustic supply
Unit 057: Flare: 115meters height
Unit 059: Fire water: Two tanks
Unit 100: RO: Silica Seperating
Unit 032: Steam: - Low pressure steam(LPS): 3–6

Section
Hot Utility

kg/cm2

- MPS: 14-16 kg/cm2
- HPS: 40-42 kg/cm2
- HHPS: 100-105 kg/cm2
Unit 040: STG: Power Station - There are four transmitters.While 3 of
those generators run at 50%, 50%, 100%, and the remaining machines
are redundant
Unit 038: – Fuel oil
Unit 051: Intermediate tankge: 23 tankage
Unit 054: – Blending Unit
Unit 055: Flushing oil: Using LGO from CDU to clean pipes system.
Unit 056: Slops oil: Collect oil from units, provide for CDU, RFCC unit.


Offsite P1

Unit 060: Crude oil tankge -Included 8 tanks, each tank has the capacity
of 65.000m3, 22.4m height, diameter 69m
Unit 052: Product tankge: 22 product tanks including 5 petrol tanks, 3
propylene tanks, 5 LPG tanks, 1 slops oil
Unit 053: Truck loading: Each truck has 13m3 loading
Unit 081: Jetty Topside:

Offsite

There are 6 berths: 4 berths, each carrying 1000-5000m3, 2 berths each
carrying 15000-30000m3
Unit 082: SinglePoint Mooring (SPM): d=12m, 5m height (3,75m under


the sea)
Unit 071: Interconnecting Pipleline (P1 P3) - 12 pipelines: 8 product
pipelines and 4 auxiliary pipelines, total 7km long.
P3/Jetty

Interconnecting Pipleline (P3
Jetty): There are 15 pipelines: 10
product pipelines, 5 waste oil extraction lines and ballast water, 3km
long.
Unit 072:

Here are some main products of Dung Quat Refinery:
- Types of products:
+ Propylene

+ Liquefied Petroleum Gas (LPG)
+ Gasoline Mogas (A-90/92/95 RON gasoline)
+ Domestic jet / fuel oil
+ Automotive diesel fuel (DO )
+ Fuel oil (FO).

- Product’s Capacity:
Products name

x106 tons/year

Propylene

110 - 150

LPG

280 - 300

Gasoline Mogas 90/92/95

2000 - 2500

Kerosene /Jet Fuel A1

400 - 410

Diesel

2500 - 3000


Fuel Oil (FO)

300 - 350

Fuel for the plant/jet

470 - 490


Table 1.2: Product’s Capacity
Product quality: For products consumed domestically in accordance with product
quality standards of Vietnam. For export products must reach the requirements of
export quality.
When reached the maximum capacity, Dung Quat Refinery will produce 150,000 tons
of petrol, 240,000 tons of diesel, about 23,000 tons of LPG and other products such as
propylene over 8,000 tons, Jet-A1 gasoline (about 30,000 tons) and FO oil (about
25,000 tons). Dung Quat refinery will meet about 30% of petroleum demand in the
country, step by step ensure the number one spot of national energy providing.


Chapter 2 - Introduction of Crude Distillation
Unit (CDU)

2.1 Introduction of Crude Distillation Unit (Unit 011) of Dung Quat
Refinery
The Crude oil Distillation Unit (CDU) can be considered as a "gateway" workshop of
a refinery that separates crude oil into smaller segments at different boiling points.
The CDU plant of Dung Quat Refinery is designed with a capacity of 6.5 million tons
of crude oil per year, equivalent to 812,500 kg / h (calculated for 8,000 hours per

year).
The CDU is designed to operate on two sources of oil: Bach Ho Oil of Vietnam and
Dubai Oil of the foreign Middle East. According to plans, in the first phase of
operation, the plant will use 100% raw material of Bach Ho crude oil. And then use
the mixed oil source of 84.6% Bach Ho Oil and 15.4% Dubai Oil.
CDU's products included Offgas, LPG, Full Range Naphta, Kerosene, LGO, HGO and
atmospheric distillate residues. Most of the CDU's products go to other units such as
Unit 012 - NHT ( Naphta Hydrotreatment Unit), Unit 014 - KTU ( Kerosen Treating
Unit), Unit 015 - RFCC ( Residue Fluidised Catalytic Cracking Unit) ... The diagram
of the workshops of Dung Quat Oil Refinery is shown in Figure below.


Figure 2.1 Crude Distillation Unit (Unit 011) of Dung Quat Refinery


According to the Figure 1, the area covered with a rectangular frame is the
atmospheric distillation CDU. With two main units are the T-1101 (Main
FRACTIONATOR) and the T-1107 (Stabilizer).
As you can see on the plant figure, the crude oil stream passing through the Preheater
System and the Salt Separater then moving to the main fractionator ( T-1101 ). In here
the crude oil will be separate into some main products:
- Light products output from the top of the CDU distillation column is fed through the
RFCC processing unit and then through the liquefied petroleum gas (LPG) treatment
plant.
- The naphtha feed is taken to the Naphtha treatment plant processing by hydrogen
and then goes to the naphtha separation tower, where Naphtha is split into light
naphtha and heavy naphtha.
- Light naphtha from the separation tower is taken to the Isomerization unit.
- Heavy Naphtha from the separation tower is taken to the Continuous Reforming
Catalytic Unit.

- Kerosene stream from the atmospheric distillation unit is delivered directly to the
Kerosene tankge storage or used as a mixing material for diesel and fuel oil, or it is
transported to a Kerosene treatment plant ( KTU). In the KTU the content of
mercaptan (RSH), hydrosulfide (H2S) and naphthenic acid (RCOOH) are reduced and
water removed. The treated Kerosene was then taken to the reservoir where it was
used as jet fuel JetA1.
- The LGO from the atmospheric distillation plant is injected directly into the Diesel
blending system and finally to the storage tank at the Product tankages.
- The HGO is pumped to the storage tank at the plant through pipes system, from
which it is pumped to the diesel /fuel oil blending system.
- The residues from the CDU was transferred to the RFCC to upgrade to higher value
products.


3D strucuture of Crude Distillation Unit with the view of South East and West East are
shown in these figure below:

Figure 2.2: 3D strucuture of Crude Distillation Unit from South East


Figure 2.3: 3D sstrucuture of Crude Distillation Unit from West East

2.2 Mission of Crude Distillation Unit (Unit 011)
The purpose of the CDU workshop is to separate preliminary crude oil to produce
products as raw materials for subsequent processing units and the direct mixing
constituents for some products
Crude oil is heated by the product streams and the flow circulating reflux
(Pumparound) before being taken to the furnace heater. Preliminary separation
process crude oil is conducted in the main separated tower and the side separated
separation tower (Stripper). Naphtha line separated from the main tower Tl-101

are brought to a stable tower gas (Stabilizer) Tl-107. The other product is cooled
before being put straight to intermediate storage tanks or workshops for
appropriate depth processing. Particularly, LGO and HGO are dried by vacuum
before being transported to an intermediate storage tank or LCO-HDT unit.