1. Gas Plant Unit Processing
Prepared by:
Bafreen Amjad Aza M.Ali
Darya Mahdi Harikar Mekail
Safeen Dlshad
Supervisor
MR. Abdulsalam Daneshvar
University of Zakho
College of Engineering
Petroleum Engineering Dep.
2. Petroleum & natural
gas formation
Role of gas plant
Introduction
Important
support
components
Utilities
Safety systems
Process control
Plant
processes
List of content
Gas Treating
Gas Dehydration
Outlet Compression
Liquids Processing
Sulfur Recovery
Inlet Compression
Storage And Transportation
Field Operations And Inlet Receiving
3. ďś Natural gas :A mixture of gaseous hydrocarbons occurring in reservoirs of
porous rock (commonly sand or sandstone) capped by impervious strata. It is
often associated with petroleum, with which it has a common origin in the
decomposition of organic matter in sedimentary deposits.
3
INTRODUCTIONOutline
âşIntroduction
⌠Petroleum & natural
gas formation
⌠Role of gas plant
⌠Plant processes
⢠Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Bafreen Amjad
Methane (CH4)
Ethane (C2H6)
Propane (C3H8)
Condensate (C5H12 â C10H22)
Nitrogen (N2)
Carbon Dioxide (CO2)
Hydrogen Sulphide
(H2S)Helium (He)
4. 4
industry wise consumption of natural gasOutline
âşIntroduction
⌠Petroleum & natural
gas formation
⌠Role of gas plant
⌠Plant processes
⢠Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Bafreen Amjad
5. 5
PETROLEUM AND NATURAL GAS FORMATION
Tiny marine plants and
animals died and were
buried on the ocean floor.
Over time, the marine
plants and animals were
covered by layers of silt
and sand.
Over million of years, the
remains were buried deeper
and deeper. The enormous
heat and pressure tumed
the remains into oil and
natural gas.
Today, we drill down through
layers of sand, silt, and rock
to reach the rock formations
that contain oil and natural
gas deposits.
Outline
ďź Introduction
âşPetroleum & natural
gas formation
⌠Role of gas plant
⌠Plant processes
⢠Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Bafreen Amjad
6. 6
ROLE OF GAS PLANT
⢠Gas plants play a variety of roles in the oil and gas industry. Some
primary purposes plants include:
ďś Dehydration of gas to reduce corrosion and to prevent gas hydrate
formation. These plants commonly are found on offshore platforms,
where associated gas is separated from oil and dehydrated.
Depending upon pipeline infrastructure, the gas may be recombined
the before it is put into pipeline to shore.
ďś Upgrading sub quality gas. To make the gas marketable, the
undesired diluents N2, H2S, and CO2 are removed. Of the three
components, N2 is the most difficult to remove because it requires
cryogenic processing when large volumes are processed
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
âşRole of gas plant
⌠Plant processes
⢠Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Bafreen Amjad
7. 7
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
âşRole of gas plant
⌠Plant processes
⢠Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Bafreen Amjad
8. GAS PLANT PROCESSES
8
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
âşPlant processes
⢠Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Aza M.Ali
9. GAS PLANT PROCESSES
9
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
âşPlant processes
⢠Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Aza M.Ali
10. Effect of impurities found in Natural GasOutline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
âş Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Aza M.Ali
10
11. FIELD OPERATIONS AND INLET RECEIVING
ďą Field processing operations are thus enforced to treat the natural gas
in order to meet the requirements and specifications set by the gas
transmission companies.
ďą The main objective is to simply obtain the natural gas as a main
product free from impurities.
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
âş Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
11
Aza M.Ali
12. FIELD OPERATIONS AND INLET RECEIVING
ďś Which is classified as a part of gas engineering, generally include the
following:
1. Removal of water vapor,
dehydration
2. Removal of acidic gases
(H2S and CO2)
3. Separation of heavy hydrocarbons
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
âş Field operations and
inlet receiving
⢠Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
12
Aza M.Ali
13. INLET COMPRESSION
ďą Most plants have inlet compression, but compression requirements
vary.
ďą In gas transmission, two basic types of compressors are used:
reciprocating and centrifugal compressors.
ďą Reciprocating compressors are usually driven by either electric
motors or gas engines.
ďą While centrifugal compressors use gas turbines or electric motors as
drivers.
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
âş Inlet compression
⢠Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Aza M.Ali
13
14. GAS TREATING
ďą Most plants have a gas treating step to remove the acid gases H2S
and CO2, along with other sulfur impurities.
ďą Most plants use water-based absorbents to remove the impurities, but
other solvents and processes are used.
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
âş Gas treating
⢠Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Aza M.Ali
14
15. GAS DEHYDRATIONOutline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
âş Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Harikar Mikail
15
ďą The process of removing water from gas
ďą Process of dehydration
Determination of
Water Content
Using Glycol
Dehydrator
four-bed
molecular sieve
unit
16. GAS DEHYDRATIONOutline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
âş Gas Dehydration
⢠Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Harikar Mikail
16
ďą Impact of Gas Dehydration
ďź Gas hydrates..
ďź Corrosion
ďź Calorific value
ďź Gas specifications.
ďź Downstream processing
17. OUTLET COMPRESSIONOutline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
âş Outlet compression
⢠Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
17
ďą Most plants must compress the gas before it goes to the
pipeline.
ďą To transport the maximum possible volume
ďą Safety
ďą To avoid the corrosion in pipelines
ďą We can transport the gas for 2000km without reduction of
pressure
Harikar Mikail
18. LIQUID PROCESSINGOutline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
âş Liquids processing
⢠Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
18
It has two separate units
ď Condensate stabilization
ď NGL treating
The process of removing H2S and lighter components
Inlet
Receiving
Condensate
Stabilization
NGL treating
Storage
Or
pipeline
Typical Sour Gas Plant with NGL Recovery
Harikar Mikail
19. SULFUR RECOVERY
ďą Sulfur recovery refers to conversion of hydrogen sulfide(h2s) to elemental sulfur.
ďą byproduct of natural gas processing comes from Hydrogen sulfide
ďą The most common conversion method clause process 90 -95 % recovery.
ďą Approximately percent of recovered sulfur is produced by the clause process.
ďą Any further conversion of the sulfur gases must be done by catalytic reaction.
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
ďź Liquids processing
âş Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Darya Mahdi
19
20. Clause process
ďą The clause process is the most significant elemental sulfur recovery process from
gaseous hydrogen sulfide .
ďą Gases with an h2s content of over 25% are suitable for the recovery of sulfur in the
clause process.
ďą The main reaction is:
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
ďź Liquids processing
âş Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
2H2S+O2 --> 2S+2H2O +heat
Darya Mahdi
20
21. Catalytic reaction complete the process
ďą The gas is reheated by one of several means and is then introduced to catalyst bed.
ďą The catalytic clause reaction release more energy and converts more than half of
remaining sulfur gases to sulfur vapor.
ďą The vapor is condensed by generating low pressure steam and is removed from gas
steam.
ďą The remaining gases are reheated and enter the next catalytic bed.
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
ďź Liquids processing
âş Sulfur recovery
⢠Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Darya Mahdi
21
22. STORAGE AND TRANSPORTATION
Storage:
Storage facilities are open for additional uses such as
ď§ Storing gas when prices are low
ď§ Selling gas when prices are high
Storage provide a volume of working gas for a long âterm steady with drawal of the
gas (typically 3to 5 months)
Natural gas storage options
ď§ Short term commercial instruments
ď§ In pipe storage âline pack
ď§ Liquefaction and regasification
ď§ Under ground storage
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
ďź Liquids processing
ďź Sulfur recovery
âş Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Darya Mahdi
22
23. STORAGE AND TRANSPORTATION
Transportation:
ďą Any of several possible gas stream are transported from the plant to customers
ďą Most gas goes to an extensive pipeline network dedicated to natural gas services.
ďą The smaller diameter lines are normally used in the gathering system which is bring
the gas from wellhead to the gas processing plant
ďą The larger lines are generally long distance transmission lines designed to bring
sales gas to customers.
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
ďź Liquids processing
ďź Sulfur recovery
âş Storage and
transportation
⌠Important support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Darya Mahdi
23
24. IMPORTANT SUPPORT COMPONENTS
ďś Some important components of all gas plants.
These components include:
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
ďź Liquids processing
ďź Sulfur recovery
ďź Storage and
transportation
âşImportant support
components
⢠Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
LNG plant in Hammerfest, Norway
Safeen Dlshad
24
I. Utilities
II. Process Control
III. Safety Systems
25. Utilities
ďą Utilities include power, heating ďŹuids (steam), cooling water, instrument air,
nitrogen-purge gas, and fuel gas.
ďą Most gas plants purchase electrical power.
ďą Cogeneration plants are becoming more attractive options for reduction of
operating costs.
ďą Cooling water is used primarily in heat exchangers on compressors.
ďą Nitrogen is used as a purge gas around rotating seals, as well as to purge and
blanket vessels.
ďą In many cases, the enriched nitrogen is obtained from membrane or pressure swing
adsorption (PSA) separation, If large volumes are required, cryogenic fractionation
of air is the most economical process.
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
ďź Liquids processing
ďź Sulfur recovery
ďź Storage and
transportation
ďź Important support
components
âş Utilities
⢠Process control
⢠Safety systems
Gas plant unit processing
Safeen Dlshad
25
26. Process Control
ďą Most plants use a distributed control system (DCS) for individual
units to provide both process control and operation history.
ďą Advanced process control (APC) system uses multivariable
algorithms that are programmed to perform online optimization.
ďą One important use of supervisory control and data acquisition
(SCADA) is the monitoring of ďŹeld operations, with the capability
of controlling the process unit equipment, ďŹow valves, and
compressor stations from the gas plant.
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
ďź Liquids processing
ďź Sulfur recovery
ďź Storage and
transportation
ďź Important support
components
ďź Utilities
âş Process control
⢠Safety systems
Gas plant unit processing
Safeen Dlshad
26
27. Safety Systems
ďą Safety systems are critical to all gas
plants.
ďą These systems include the emergency
shutdown of inlet gas, as well as relief
valves and vent systems leading to the
ďŹare
ďą Pipe ďŹares are probably the most common
ďŹare in gas plants
Outline
ďź Introduction
ďź Petroleum & natural
gas formation
ďź Role of gas plant
ďź Plant processes
ďź Field operations and
inlet receiving
ďź Inlet compression
ďź Gas treating
ďź Gas Dehydration
ďź Outlet compression
ďź Liquids processing
ďź Sulfur recovery
ďź Storage and
transportation
ďź Important support
components
ďź Utilities
ďź Process control
âş Safety systems
Gas plant unit processing
Safeen Dlshad
27