5/4/2023
Oil & Natural Gas at their Origin
Asra Nafees
➢ CLO I
• IDENTIFY the physico-chemical characteristics of petroleum and
petrochemical products.
➢ CLO II
• DESCRIBE the process and chemical transformation of petroleum and
petrochemical products.
➢ CLO III
• DESCRIBE the resources and standard test of petroleum and its products in
order to diminish the ethical and environmental issues for the development of
sustainable future.
➢ CLO IV
• EXPRESS effective presentation and actively participate in group
discussions.
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• Course Outline:
TOPICS
Introduction:
Modern exploration, production and processing operations.
Origin and fluid properties of oil and natural gas reservoir types.
Basic reservoir Engineering concepts.
Composition of petroleum:
Chemical composition of petroleum and petroleum products and their physical, chemical,
thermodynamic and performance characteristics.
Petroleum Products:
Interrelation between the chemical structure and characteristics of petroleum products.
LPG,Gasoline,Industrial Solvents,Naphtha,Kerosene,Aviation Turbine Fuel,High speed
diesel,Light,Diesel Oil,Furnace Fuels,Lubricants,Base oils,Tar and Bitumen
Basic Refinery Process:
Physical separation processes(distillation and extraction)
Chemical Transformation Processes(thermal cracking and reforming)
Molecular rearrangement processes(isomerization, alkylation,polymerization)
Molecular rebuilding Processes:
Methane
Natural Gas
CNG
Rebuilding of Hydrocarbons
Rubber.
Petrochemicals:
Methanol, Formaldehyde, Ethylene production by steam cracking of naphtha,
Ethylene dichloride, Vinyl Chloride monomer, Vinyl Acetate monomer,
Ethylene oxide,Acetaldehyde,Propylene,Acrolynitrile,PropyleneOxide,MTBE,Butadiene,
BTX separation, Benzene by dealkylation of toluene.
Refinery products:
Properties
Significant tests
Standard Test Methods.
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➢Oil & Natural Gas at their origin:
• Fluids produced from oil and gas wells generally constitute
mixtures of crude oil, natural gas, and salt water.
• These mixtures are very difficult to handle, meter, or transport.
In addition to the difficulty, it is also unsafe and uneconomical
to ship or to transport these mixtures to refineries and gas
plants for processing.
• Also, environmental constraints exist for the safe and
acceptable handling of hydrocarbon fluids and disposal of
produced salt water.
• It is therefore necessary to process the produced fluids in the
field to yield products that meet the specifications set by the
customer and are safe to handle.
Gas Oil separation Block Flow Diagram
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• Crude oil–gas–water mixtures produced from wells
are generally directed, through flow lines and
manifold system, to a central processing and treatment
facility normally called the gas–oil separation plant
(GOSP).
• The first step in processing of the produced stream is
the separation of the phases (oil, gas, and water) into
separate streams.
• Separation takes place in mechanical devices known
as two-phase gas–oil separators when the produced
stream contains no water or three-phase separators
when the produced stream contains water.
• Oil leaving the separator does not generally meet the purchaser’s
specifications.
• Oil may still contain between 10% and 15% water that exists mostly
as emulsified water.
• The presence of this salt water presents serious corrosion and scaling
problems in transportation and refinery operations.
• Water remaining in the oil is known as the basic sediments and water
(BS&W). A maximum of 1% BS&W and in some cases less than
0.5% BS&W is acceptable.
• The limit on the salt content of the remnant water in oils is usually in
the range of 10 to 15 PTB (pounds of salt per thousand barrels of oil).
• If these specifications are not met, then further treatment of the oil
leaving the separator will be needed. Such treatment involves
emulsion treatment/dehydration and desalting processes.
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• After oil treating, there may be a need to stabilize the crude oil
to optimize the oil recovery and reduce its volatility.
• Some produced crude oils contain hydrogen sulfide and other
sulfur products. When it contains more than 400 ppm of H2S
gas, the oil is classified as sour crude.
• Sour crude oils present serious safety and corrosion problems. In
such cases, another treatment known as the sweetening process
is needed to remove hydrogen sulfide or reduce its content to
acceptable limits.
Sales Gas
Sulfur
Fractionation
Plant
Gas Plant
GOPs
Ethane
Propane
Butane
Natural Gasoline
Sales Gas
Sulfur
GOPs
Gas Plant
Ethane
Sales Gas
Sulfur
NGL
Fractionation
Plant
Propane
Butane
Natural Gasoline
GOPs
Gas Plant
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Well Head
A component at the surface
of an oil or gas well that
provides the structural and
pressure-containing interface
for the drilling and
production equipment.
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Manifold System:
Onshore, the individual well streams
are brought into the main production
facilities over a network of gathering
pipelines and manifold systems.
The purpose of these is to allow set up
of production “well sets” so that for a
given production level, the best
reservoir utilization, well flow
composition (gas, oil, waster) etc. can
be selected from the available wells.
Gravity settler:
In gravity separation the well flow is fed
into a horizontal vessel.
The retention period is typically 5 minutes,
allowing the gas to bubble out, water to
settle at the bottom and oil to be taken out in
the middle.
The pressure is often reduced in several
stages (high pressure separator, low pressure
separator etc.) to allow controlled separation
of volatile components.
A sudden pressure reduction might allow
flash vaporization leading to instabilities
and safety hazards.
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