Adhi Gas Condensate Field LPG/NGL recovery plant.
Adhi Gas Condensate Field LPG/NGL Recovery Plant
Liquefied Petroleum/Natural Gas Liquids Recovery Plant at Adhi Gas Condensate Field was recently inaugurated by the Federal Minister for Petroleum and Natural Resources, Chaundhry Nisar Ali Khan. Adhi is a Joint Venture Operation between Oil & Gas Development Corporation (OGDC OGDC Oil & Gas Development Company (Pakistan)
OGDC Office of Geographic Data Coordination (Australia) ), Pakistan Petroleum Limited (PPL), and Government of Pakistan Government of Pakistan (Urdu: حکومتِ پاکستان), The Constitution of Pakistan provides for a Federal Parliamentary System of government, with a President as the Head of State and an indirectly-elected Prime with a shareholding of 50%, 39% and 11% respectively. PPL acts as the Operator for the Lease under the Adhi Joint Venture Agreement.
Adhi Field is located about 35 miles south of Islamabad in Rawalpindi district. This area forms the eastern part of the Potwar Basin which is a proven oil producing region.
Potwar Basin is known to be amongst the most difficult drilling areas in the world due to the presence of high pressure formation water at shallow depths.
PPL jointly with Pakistan Oil Fields Limited (POL) drilled four wells at Adhi between 1956 and 1967. All these wells were abandoned due to high pressure inflow of formation water and subsurface structural complications.
The East Potwar Block in which Adhi is located was granted to PPL and AMOCO AMOCO American Oil Company in 1975.
After some additional seismic surveys in the areas, Well 5 was drilled in 1978. This well drilled to a depth of 2810 meters, proved movable hydrocarbons in Khewra, Tobra and Sakesar formations. The Sakesar formation contained 31 degrees API crude while Khewra and Tobra reservoirs were gas condensate. The well was successfully completed and put on production from Sakesar in March, 1980.
In 1981 AMOCO relinquished their 50% interest in the Block which was then assigned to OGDC.
Wells 6,7 and 8 were drilled in 1980-81. Wells 6 and 8 were abandoned due to drilling problems while Well 7 was successfully completed in Sakesar. During initial testing in early 1980, Adhi Well 5 (Sakesar) flowed about 2,000 barrels per day Barrels per day (abbreviated BPD, bbl/d, bpd, bd or b/d) is a measurement used to describe the amount of crude oil (measured in barrels) produced or consumed by an entity in one day. of crude oil with negligible water-cut. Watercut, however, increased very rapidly to almost 90% after 4 years of production. Adhi Well 5 was, therefore, worked-over in 1984 to produce gas condensate selectively from Tobra or Khewra formations. Well 9 was completed as a dual producer from Tobra and Khewra.
Adhi Field continued to produce about 2,000 barrells per day of crude and condensate, but the gas which also contained propane and butane that could be converted to Liquefied Petroleum Gas liquefied petroleum gas or LPG, mixture of gases, chiefly propane and butane, produced commercially from petroleum and stored under pressure to keep it in a liquid state. (LPG) was being flared.
A comprehensive reservoir simulation study of the condensate reservoirs was conducted in 1985 in which various options for producing the field were examined.
On the basis of this study it was decided to instal an LPG/NGL (Natural Gas Liquids) Recovery Plant at Adhi to produce gas condensate from Khewra and Tobra reservoirs. Two more wells (Nos. 10 and 11) were also drilled and completed in these two reservoirs to increase production.
In July, 1988, a turnkey contract for supply and installation of an LPG/NGL Recovery Plant was awarded to NKK Corporation of Japan.
The Plant was installed and commissioned in December, 1990, at a total cost of Rs. 250 million and is now producing at its design capacity of 19 million cubic feet per day of gas, 60 metric tons per day of LPG and 3,000 barrels per day of NGL NGL - A dialect of IGL. .
NGL is supplied to Attock Refinery Limited for further processing and disposal, LPG is supplied to designated marketing companies, while the gas is supplied to SNGPL SNGPL Sui Northern Gas Pipelines Limited (Pakistan) for its Islamabad gas distribution network.
Based on a detailed study undertaken for Adhi Field development, it is estimated that Adhi Field with original recoverable reserves of 10.220 million barrels of condensate and 0.116 trillion cubic feet of gas, will sustain, gradually decreasing production upto the year 2010.
PHOTO : A view of the LPG/NGL Recovery Plant of the Adhi Gas Condensate Field operated by Pakistan Petroleum Ltd.