The document describes the process of refining crude oil at an oil refinery. It discusses that crude oil is a complex mixture of hydrocarbons extracted from underground that is refined through processes like distillation, cracking, and reforming. The refining process involves separating crude oil through a crude distillation unit and vacuum distillation unit. Further stages include conversion processes that break down larger molecules into lighter products, as well as hydrotreating to remove impurities. The overall refining process transforms crude oil into useful products like gasoline, diesel, and feedstocks for petrochemicals.

1. Koya University
Faculty of Engineering
Chemical Engineering Department
3rd Stage (2021-2022)
Instructor
Dr. Aso Abdulkareem
Prepared by:
Safeen Yaseen Jafar
Rivan Dler Ali
Ramazan Shkur Kakl
Ibrahim Ali
Submitted On
27 Mar. 2022
Plant Design
Oil Refinery

2. Table of Contents
Abstract...........................................................................................................................................1
1. Introduction................................................................................................................................2
2. What is Crude Oil?....................................................................................................................3
3. Crude Oil Refining Process Overview .....................................................................................3
4. Oil Refining Stages.....................................................................................................................4
4.1. Separation ............................................................................................................................4
4.1.1. Crude Oil Distillation Unit (CDU/ADU) ....................................................................4
4.1.2. Vacuum Distillation Unit (VDU).................................................................................4
4.2. Conversion ...........................................................................................................................5
4.3 Treatment or Hydrotreating Unit (Purification)...............................................................5
5. Conclusion ..................................................................................................................................6
6. References...................................................................................................................................7

3. OIL REFINERY 1
Abstract
Petroleum refinery or oil refinery is the plant or facility for changing the crude oil into
useful products and feedstocks to use in the petrochemicals. As we know crude oil is the mixture
of hydrocarbons, So, to change this raw material many units necessary such as distillation process,
cracking and reforming, etc. During this report we learn that what the crude oil is, how it refines,
what is the process steps of the typical refinery.

4. OIL REFINERY 2
1. Introduction
Petroleum refinery is one of the industrial process plants of the crude oil which is the most
source for make other energy forms. Petroleum is a complex mixture of hydrocarbons that present
in the under earth’s surface in liquid, gaseous, and solid forms or phases. The term of "petroleum"
is most normally associated with liquid petroleum, although it also encompasses natural gas and
solid bitumen. Petroleum is derived from the Latin words Petra (it means rock) and oleum (it means
oil). It is normally referred to as "rock oil". [1]
Raw petroleum or crude oil is a normally happening oil based good made out of
hydrocarbon stores and other natural materials. A sort of nonrenewable energy source, unrefined
petroleum is refined to deliver usable items including fuel, diesel, and different types of
petrochemicals. It is a nonrenewable
resource. [2]
So, to understanding our topics
here we must know more details about the
refining process of the crude oil or by
another word about the petroleum
refinery’s process. In the oil refining
process, fuel oil, gas, naphtha, and
different substances are refined from raw
petroleum. This interaction uses the FCC framework, hydrogenation desulfurizing framework, and
other different coincidental offices for which further developed effectiveness and cycle the board
are required. [3]
Fig. 1: Crude oil is one of the most common
sources which can change to another energy form.

5. OIL REFINERY 3
2. What is Crude Oil?
Crude oil is the term that refers to the unprocessed oil, or it can be defined as the oil that is
extracted from the underground. Also, this crude oil is ordinarily gotten through boring, where it
is typically found close by different assets, like flammable gas and saline water. After its
extraction, unrefined petroleum is refined and handled into an assortment of structures, like fuel,
lamp oil, and black-top, available to be purchased to shoppers. [4]
3. Crude Oil Refining Process Overview
In the refinery we have some main stages and large number of units for changing this raw
material to useful products and to make a final product. So, refining is the process of separating
and altering the various components of crude oil using physical and chemical reactions. Petrol
processing plants change unrefined petroleum into oil based commodities for use as fills for
transportation, warming, clearing streets, and producing power and as feedstocks for making
synthetic substances. Refining separates raw petroleum into its different parts, which are then
specifically reconfigured into new items. there are refining process steps in this plant in these
common units: Desalting process,
Crude distillation unit (CDU), Vacuum
distillation unit (VDU), Thermal
cracker, Hydrotreaters, fluidized
catalytic cracker, Separators, Naphtha
splitter, Catalytic Reformer, Alkylation
and isomerization, Gas treating
Blending pools, Stream splitters, Claus
process. [5]
Fig. 2: Crude oil refining process flow diagram.

6. OIL REFINERY 4
4. Oil Refining Stages
4.1. Separation
Crude oil is fed and heated through into furnaces in modern separation. The liquids and
vapors that arise are pumped into distillation units. Atmospheric distillation units are used in all
refineries, while vacuum distillation units are found in more complicated refineries. Crude oil is
distilled in two units: first, in
an Atmospheric Distillation
Unit (also known as Crude
Distillation Unit, CDU), and
then in a Vacuum Distillation
Unit, where the residue from
atmospheric distillation is
further processed (VDU). [6]
4.1.1. Crude Oil Distillation
Unit (CDU/ADU)
The different hydrocarbons in raw petroleum have different boiling temperatures, the initial
step is to isolate them utilizing a cycle called atmospheric fractionation/distillation (ADU). The
refining system.
4.1.2. Vacuum Distillation Unit (VDU)
The residue from the atmospheric process is normally transported to a second distillation
column, where the operation is repeated under vacuum in order to extract more heavy distillates.
Vacuum distillation is the name for this method. [7]
Fig. 3: Common schematic diagram of the separation unit
(CDU and VDU)

7. OIL REFINERY 5
4.2. Conversion
Heavy, lower-value distillation fractions can be processed further into lighter, higher-value
products like gasoline after distillation. This is where fractions from the distillation units are
converted into streams, which are then processed into final products. In conversion we have some
units that use to re-arrange the molecules and cracking the heavy molecules to light and more
useful products as follow:
• Catalytic reforming and isomerization are two of the most frequently used methods for re-
arranging hydrocarbons.
• Cracking processes are catalytic cracking, catalytic hydrocracking using hydrogen and thermal
cracking.
• And other processes for
further refining are:
Alkylation, Catalytic
Reforming, Catalytic
Reforming,
Isomerization. [8]
4.3 Treatment or Hydrotreating Unit (Purification)
A process in which the petroleum input stream combines with hydrogen at high
temperature and pressure in the presence of a catalyst is known as hydrotreating, hydroprocessing,
or hydrodesulfurization. Sulfur, nitrogen, and heavy metals are naturally present in crude oil and
are undesirable in motor fuels. These compounds are removed using the hydrotreating process,
Fig. 4: Typical block diagram of crude oil conversion.

8. OIL REFINERY 6
which binds them with hydrogen, absorbs them in separate columns, or adds acids to eliminate
them. The compounds that are recovered are subsequently sold to other companies. Sour crude
refineries create more sulfur than refineries that handle sweet crudes. [9]
Fig. 5: This figure shows the hydroprocessing with including hydrotreating unit.
5. Conclusion
To conclude the oil refinery in this report we defined the crude oil and some brief detail
about the operation of the process of the refining. Also, we talked about main stages of the
refinery and crude oil separation because it is the mixture not pure and some basic units that
necessary to give us a good product. And we must know that crude oil has many benefits and it
has an alternative such as a renewable energy so, we need to know this crude oil (this kind of
energy) may be not a good for every time or forever, because of that we need to use renewable
energy sources.

9. OIL REFINERY 7
6. References
1. J. CHEN, "Oil Refinery," 17 Jun 2020. [Online]. Available:
https://www.investopedia.com/terms/o/oil-refinery.asp. [Accessed 26 Mar 2022].
2. N. HUSSAIN, "Hydrotreating Process in Oil Refinery," 21 Nov 2020. [Online].
Available: https://thepetrosolutions.com/hydrotreating-process-in-oil-refinery/.
[Accessed 26 Mar 2022].
3. T. E. o. E. Britannica, "crude oil. Encyclopedia Britannica.," 27 May 2020. [Online].
Available: https://www.britannica.com/science/crude-oil. [Accessed 26 May 2022].
4. P. Craig Freudenrich, ""How Oil Refining Works"," 4 Jan 2001. [Online]. Available:
https://science.howstuffworks.com/environmental/energy/oil-refining3.htm.
[Accessed 26 Mar 2022].
5. K. AMADEO, "What Is Crude Oil?," 13 Aug 2021. [Online]. Available:
https://www.thebalance.com/crude-oil-prices-trends-and-impact-on-the-economy-
and-you-3305738. [Accessed 26 Mar 2022].
6. M. RAMKUMAR, "What Is Crude Oil Refining and How Does It Work?," 26 Jul
2020. [Online]. Available: https://marketrealist.com/2016/11/crude-oil-refining/.
[Accessed 26 Mar 2022].
7. M. D. Pipaliya, 29 Jul 2020. [Online]. Available:
https://www.linkedin.com/pulse/crude-oil-characteristics-distillation-process-
manojkumar-pipaliya/. [Accessed 26 Mar 2020].

10. OIL REFINERY 8
8. J. A. Dutton, "Atmospheric and Vacuum Distillation Units," 16 Apr 2014. [Online].
Available: https://www.e-education.psu.edu/fsc432/content/atmospheric-and-
vacuum-distillation-units. [Accessed 26 Mar 2022].
9. ektinteractive, ""Refinery Processes – Lesson Overview"," 10 Jan 2021. [Online].
Available: https://ektinteractive.com/refining/refinery-processes/. [Accessed 26 Mar
2022].