Energy and resources

1. 1
Liquid Fuels
Unit II
CHE 231: Energy Resources and Utilization
Dr. Sanjay Katheria

2. 2
Direct Liquefaction Processes: Steps
Despite feasibility in technologies, coal liquefaction, either direct or indirect, unfortunately, at least in mid-term can not be of
competitiveness in face of cheep crude oil.
1. Thermal Decomposition: Carbonization, removal of volatile impurities
One typical example of carbonization is the Karrick process. In this low-temperature carbonization process, coal is heated at
680 °F (360 °C) to 1,380 °F (750 °C) in the absence of air. These temperatures optimize the production of coal tars richer in
lighter hydrocarbons than normal coal tar. However, any produced liquids are mostly a by-product and the main product is
semi-coke - a solid and smokeless fuel.
2. Hydrogenation:
In this process, dry coal is mixed with heavy oil recycled from the process. A catalyst is typically added to the mixture. The
reaction occurs at between 400 °C (752 °F) to 500 °C (932 °F) and 20 to 70 MPa hydrogen pressure. The reaction can be
summarized as follows:

3. 3
Origin of Oil/Petroleum
The Organic theory is the most widely accepted
theory about the origin of petroleum. According to
organic theory, oil and gas were formed from the
remains of prehistoric plants and animals.
These remains were settled into seas and lands
along with sands and silts, mud, and other minerals.
Over a few million years, the layers of the organic
material were compressed under the weight of the
sediments above them.
The increase in pressure and temperature with the
absence of oxygen changed the mud, sand, silt or
sediments into rock and organic matter into
Kerogen.
After further burial and heating, the kerogen transformed via cracking into petroleum and natural gas.

4. 4
Origin of Oil/Petroleum
There are three necessary components in the
generation and accumulation of oil: source rock,
reservoir rock, and cap rock.
Source rock is a rock with high concentration of
organic material that can be transformed into oil
under the action of high temperature.
Not every organic material can be transformed into oil, for example, wood can form only coal and methane.
The remains of algae can transform into oil and, at higher temperatures, into natural gas.
Oil window (temperature range):
Geologists often refer to the temperature range in which oil forms as an "oil window". Below the minimum temperature oil
remains trapped in the form of kerogen. Above the maximum temperature the oil is converted to natural gas through the
process of thermal cracking.

5. 5
Kerogen
Kerogen is solid, insoluble organic matter in sedimentary rocks. It consists of a variety of organic materials, including dead
plants, algae, and other microorganisms, that have been compressed and heated by geological processes
https://petroshine.com/source-rocks/3/ Sci Rep 7, 12530 (2017).

6. 6
Oil migration and accumulation
The transport of petroleum from the source rock to the
reservoir rocks is called migration which occurs along
permeable carrier beds.
There are two types of migration when discussing the
movement of petroleum, primary and secondary. Primary
migration refers to the movement of hydrocarbons from source
rock into reservoir rock and it is this type that the following
discussion refers to.
Secondary migration refers to the subsequent movement of hydrocarbons within reservoir rock; the oil and gas has left the
source rock and has entered the reservoir rock. This occurs when petroleum is clearly identifiable as crude oil and gas although
the gas may be dissolved in the oil. Buoyancy of the hydrocarbons occurs because of differences in densities of respective
fluids and in response to differential pressures in reservoir rock.
https://www.dnr.louisiana.gov/assets/TAD/education/BGBB/3/

7. 7
World Petroleum Reserve
http://large.stanford.edu/courses/2013/ph240/malyshev2/

8. 8
Petroleum Production
Oil and gas extraction is a process that refers to the exploration and production of petroleum and natural gas from wells.
Oil Extraction
There are three common ways to explore the land for onshore oil and gas
exploration.
Seismographic methods, such as seismic prospecting, which use sound waves or
seismic waves to create a map of the rock formations underground.
Gravity and magnetic surveying, which work with the help of a gravimeter to pick
up gravitational force in the earth, or a magnetometer attached to an aircraft or
aquatic vessel to assess rock formations based on their response to the magnetic
fields around them.
Surface methods, which is about observing either the geological features of the
area to understand the rock formations there, the hydrocarbon seeping into the
ground, or both.
1. Oil Exploration

9. 9
Petroleum Production
2. PREPARING THE RIG SITE

10. 10
Petroleum Production
2. Drilling

11. Petroleum Production
2. Drilling
CONVENTIONAL OIL
Conventional oil is a term used to describe oil that can be produced
(extracted from the ground) using traditional drilling methods. It is liquid
at atmospheric temperature and pressure conditions, and therefore flows
without additional stimulation. This is opposed to unconventional oil,
which requires advanced production methods due to its geologic
formations and/or is heavy and does not flow on its own.
Pumpjack
A pumpjack is the overground drive for a reciprocating piston pump in an
oil well. It is used to mechanically lift liquid out of the well if there is not
enough bottom hole pressure for the liquid to flow all the way to the
surface. The arrangement is often used for onshore wells. Pumpjacks are
common in oil-rich areas.
https://www.capp.ca/oil/extraction/
11

12. Petroleum Production
2. Drilling
UNCONVENTIONAL OIL
Unconventional oil cannot be recovered using
conventional drilling and pumping methods. Advanced
extraction techniques, such as oil sands mining and in
situ development, are used to recover heavier oil that
does not flow on its own
Oil found in geological formations that make it more
difficult to extract, such as light tight oil (LTO), is also
called unconventional oil because non-traditional
techniques are needed to extract the oil from the
underground reservoir.
https://www.capp.ca/oil/extraction/
12

13. Petroleum Production
2. Drilling
UNCONVENTIONAL OIL
Unconventional (oil & gas) reservoirs, or
unconventional resources (resource plays)
are accumulations where oil & gas phases
are tightly bound to the rock fabric by
strong capillary forces, requiring specialized
measures for evaluation and extraction.
13

14. Petroleum Production
2. Drilling
2014 Oil Price Decline
Factors Behind the 2014 Oil Price Decline Bank of Canada Review • Autumn 2017
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15. Petroleum Production
2. Drilling
Hydrofracking
Fracking is an extraction technique for oil and gas wells in which
rocks are fractured artificially using pressurized liquid.
The process involves drilling down into the earth and injecting a
highly pressurized mixture of water, sand, and thickening agent, also
called "fracking fluid," into a wellbore to create cracks in rock
formations.
Once the hydraulic pressure is removed from the well, the remnants
of the fracking fluid hold the fractures open, making it easy to extract
the oil and gas inside. 15

16. Petroleum Production
STEP 3: CEMENTING AND TESTING
STEP 4: WELL COMPLETION
STEP 5: FRACKING
STEP 6: PRODUCTION AND FRACKING FLUID RECYCLING
STEP 7: WELL ABANDONMENT AND LAND RESTORATION
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17. Crude Oil Pretreatment
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Demulsifying
Crude oil emulsion is formed as dispersed water phase in an oil medium. The water globules are protected by an oil layer
which prevents their coalescence. This protective oil layer increases in mechanical strength with time (aging) due to long
storage, thus stabilizing the emulsion.
Chemical demulsifiers or emulsion breakers are used to break the crude oil emulsion into oil and water phases. They destroy
the interfacial film and enhance the coalescence of the water droplets. Some chemical demulsifiers include amines, polyhydric
alcohols, acids, and polymers.
Deasphalting
Heavy oils contain significant amounts of asphaltenes which, if not removed, will decrease the efficiency of the refining process
and reduce product quality. Asphaltenes comprise a dark brown to black solid with no definite melting point but foams and
swells when heated leaving a carbonaceous residue. Their molecular weight can span from 1000 to 100,000.

18. Crude Oil Pretreatment
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Demetallization
Most crudes, especially heavy oils, contain various metals in different concentrations ranging from 1000 to a few million ppm
depending on the origin of the crude. These metals are mainly sodium (Na), potassium (K), lithium (Li), calcium (Ca), strontium
(Sr), iron (Fe), cupper (Cu), silver (Ag), manganese (Mn), tin (Sn), lead (Pb), cobalt (Co), titanium (Ti), gold (Au), chromium (Cr),
vanadium (V), and nickel (Ni).
Currently, demetallization is most commonly achieved during hydrotreating, deasphalting, and hydrocracking
Denitrogenation
Nitrogen is one of the major heteroatoms but is also present in crudes as nitrogen-containing compounds which need to be
removed from crude oil to avoid downstream problems. Common nitrogen-containing compounds are mainly in form of
complex structures such as porphyrins and quinolines as well as simple ones such as pyridine (C5H5N) and pyrrole (C4H5N),
which are prone to free radical addition reactions to form gums and amines. These react with acid catalysts and cause
deactivation.

19. Crude Oil Pretreatment
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Denitrogenation
Hydrodenitrogenation removes nitrogen by forming other compounds such as ammonia, which are then separated from the
oil.
Deoxygenation
Desulfurization
Desalting
https://www.intechopen.com/chapters/69325

20. Petroleum Refinery
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21. Petroleum Refinery
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Petroleum crude oils are complex mixtures of hydrocarbons, chemical compounds composed only of carbon (C) and hydrogen
(H).
Petroleum includes not only crude oil, but all liquid, gaseous and solid hydrocarbons.
Under surface pressure and temperature conditions, lighter hydrocarbons methane, ethane, propane and butane exist as
gases, while pentane and heavier hydrocarbons are in the form of liquids or solids.
When crude oil is input into a fractional distillation tower, there is an overall increase in volume of product. If a single barrel of
crude oil - equal to about 159 liters - were refined, the volume of the final products is actually greater than the volume of the
initial crude oil. In fact, 170 liters of refined petroleum products can be obtained from 159 liters of crude oil. There is an
increase in volume through the refining process as a result of an effect known as processing gain.

22. Petroleum Refinery
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https://en.wikipedia.org/wiki/Petroleum
Fire Debris Analysis 2008, Pages 199-233
(https://www.sciencedirect.com/science/arti
cle/abs/pii/B9780126639711500117) https://energyeducation.ca/encyclopedia/In_a_barrel_of_oil

23. Refinery Operations
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24. Basic Refinery Operations
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Fractional distillation
Fractional distillation is the process by which oil refineries separate crude oil
into different, more useful hydrocarbon products based on their relative
molecular weights in a distillation tower.
Light distillate is one of the more important fractions, and its products have boiling points
around 70-200°C. Useful hydrocarbons in this range include gasoline, naphta (a chemical
feedstock), kerosene, jet fuel, and paraffin. These products are highly volatile, have small
molecules, have low boiling points, flow easily, and ignite easily.
Medium distillate are products that have boiling points of 200-350°C. Products in this range
include diesel fuel and gas oil - used in the manufacturing of town gas and for commercial
heating.
Heavy distillate are the products with the lowest volatility and have boiling points above 350°C. These fractions can be solid
or semi-solid and may need to be heated in order to flow. Fuel oil is produced in this fraction. These products have large
molecules, a low volatility, flow poorly, and do not ignite easily.

25. Basic Refinery Operations
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Vacuum distillation
Standard petroleum fractions withdrawn from the vacuum distillation column include lube distillates, vacuum oil, asphalt
stocks, and residual oils.
The vacuum in the vacuum distillation column is usually maintained by the use of steam ejectors but may be maintained by
the use of vacuum pumps.
Temperature constraint of Atmospheric distillation (less than 370 to 380 °C) yields a residual oil from the bottom of the
atmospheric distillation column consisting entirely of hydrocarbons that boil above 370 to 380 °C.
To further distill the residual oil from the atmospheric distillation column, the distillation must be performed at absolute
pressures as low as 10 to 40 mmHg / Torr (About 5% atmospheric pressure) so as to limit the operating temperature to less
than 370 to 380 °C.

26. Basic Refinery Operations
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Vacuum distillation
Clausius-Clapeyron Equation
where P1 and P2 are the vapor pressures at two temperatures T1 and T2 .
Clausius-Clapeyron Equation allows us to estimate the vapor pressure at another temperature, if the vapor pressure is
known at some temperature, and if the enthalpy of vaporization is known.
https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Physical_Properties_of_Matter/States_of
_Matter/Phase_Transitions/Clausius-Clapeyron_Equation
The Antoine equation is a class of semi-empirical correlations describing the relation between vapor pressure and temperature
for pure substances. The Antoine equation is derived from the Clausius–Clapeyron relation.
August equation

27. Basic Refinery Operations
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Hydrodesulfurization
Hydrodesulfurization is a high-pressure (150 to 250 psig) and high-temperature (200 to 425°C) process that uses hydrogen gas
to reduce the sulfur in petroleum fractions (particularly diesel) to hydrogen sulfide, which is then readily separated from the
fuel.
https://www.e-education.psu.edu/fsc432/content/hydrodesulfurization

28. Basic Refinery Operations
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Hydrodesulfurization
https://en.wikipedia.org/wiki/Hydrodesulfurization

29. Basic Refinery Operations
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Catalytic reforming is a chemical process used to convert petroleum refinery naphthas distilled from crude oil (typically having
low octane ratings) into high-octane liquid products called reformates, which are premium blending stocks for high-octane
gasoline.
The process converts low-octane linear hydrocarbons
(paraffins) into branched alkanes (isoparaffins) and cyclic
naphthenes, which are then partially dehydrogenated to
produce high-octane aromatic hydrocarbons.
The most valuable byproduct from catalytic reforming is hydrogen to satisfy the increasing demand for hydrogen in
hydrotreating and hydrocracking processes.
Most reforming catalysts contain platinum as the active metal supported on alumina, and some may contain additional metals
such as rhenium and tin in bi- or tri-metallic catalyst formulations.

30. Basic Refinery Operations
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Catalytic Reforming Reactions
• Dehydrogenation: naphthenes → aromatics
the conversion methylcyclohexane (a naphthene) to toluene (an aromatic)
• Paraffins are isomerized: the conversion of normal octane to 2,5-
Dimethylhexane (an isoparaffin)
• aromatics are unchanged
Catalytic Reforming Feedstock and Product
aromatization of paraffins to aromatics (commonly called
dehydrocyclization) as exemplified in the conversion of normal heptane
to toluene

31. Basic Refinery Operations
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Catalytic Reforming Reactions Catalytic Reforming Feedstock and Product
• Aromatization of paraffins to aromatics (commonly called
dehydrocyclization) as exemplified in the conversion of normal
heptane to toluene
• The hydrocracking of paraffins into smaller molecules as exemplified by
the cracking of normal heptane into isopentane and ethane
https://en.wikipedia.org/wiki/Catalytic_reforming

32. Basic Refinery Operations
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Octane ratings
Octane ratings are measures of fuel stability. These ratings are based on the pressure at which a fuel will spontaneously
combust (auto-ignite) in a testing engine.
The octane number is actually the simple average of two different octane rating methods—motor octane rating (MOR) and
research octane rating (RON)—that differ primarily in the specifics of the operating conditions. The higher an octane number,
the more stable the fuel.
In broad terms, fuels with a higher octane rating are used in
higher-compression gasoline engines, which may yield higher
power for these engines. Such higher power comes from the
fuel's higher compression by the engine design, and not
directly from the gasoline.
https://www.energy.gov/energysaver/gasoline-octane-ratings-
explained#:~:text=Regular%20(the%20lowest%20octane%20fuel,fuel%E2%80%93generally%2091%E2%80%9394)

33. Basic Refinery Operations
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Alkylation
The alkylation process combines light iso-paraffins, most commonly
isobutane, with C3–C4 olefins, to produce a mixture of higher molecular
weight iso-paraffins (i.e., alkylate) as a high-octane number blending
component for the gasoline pool.
Alkylation is a chemical reaction that entails transfer of an alkyl group.
The alkyl group may be transferred as an alkyl carbocation, a free radical,
a carbanion, or a carbene (or their equivalents)

34. Basic Refinery Operations
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Isomerization
Isomerization processes have been used to isomerize n-butane to iso-butane used in alkylation and C5 /C6 n-paraffins in light
naphtha to the corresponding iso-paraffins to produce high-octane number gasoline stocks after the adoption of lead-free
gasoline
Catalytic isomerization processes that use hydrogen have been developed to operate under moderate conditions.
Polymerization
The polymerization process combines propenes and butenes to produce higher olefins with high-octane numbers (97 RON and
83 MON) for the gasoline pool.
The polymerization process was used extensively in the 1930s and 1940s, but it was replaced to a large extent by the
alkylation process after World War II.
https://www.e-education.psu.edu/fsc432/content/polymerization