The Azeri-Chirag-Gunashli (ACG) field lies 120km off the coast of Azerbaijan in 120m of water and contains 5.4 billion barrels of recoverable oil. The field was put into production in November 1997.
During the first six months of 2012, the field produced a total of 124.5 million barrels and 11.5 million cubic metres of associated gas per day from 56 production wells.
Participants of the ACG offshore field include: BP, which is operator with 35.83% stake; Chevron with 11.3%; SOCAR with 11.6%; INPEX with 11%; Statoil with 8.6%; ExxonMobil with 8%; TPAO with 6.8%; Itochu with 4.3%; and Hess with 2.7%.
In September 2012, ONGC Videsh Limited (OVL), an international arm of the Indian oil and gas company ONGC, signed an agreement to acquire Hess’s entire stake in the ACG project. The acquisition is subject to regulatory approvals is expected to be closed by 2013.
The Chirag early oil project (EOP) is a single offshore platform, producing over 125,000bpd. Production began in November 1997 and the field will reach the end of its productive life by 2024.
The Central, West and East Azeri complexes were developed under phases I and II, and the Deepwater Gunashli section was developed under phase III.
Chirag-1 is an offshore production, drilling and quarters (PDQ) platform located 120km east of Baku in the Caspian Sea. The Chirag facilities include a 24-slot PDQ platform with water-injection equipment, a 176km-long 24in oil pipeline to the receiving terminal at Sangachal, a 48km-long 16in gas pipeline to the oil rocks, a 12km-long 18in gas pipeline to Central Azeri, and a compression and water injection platform. The Chirag platform has both production and water-injection wells, which will increase oil recovery.
“The Azeri-Chirag-Gunashli field lies 120km off the coast of Azerbaijan.”
Crude comes ashore by pipeline to the Sangachal terminal south of Baku. Most is carried in the 850km western export pipeline which has a capacity of 140,000pd (peak 160,000) to the Georgian port of Supsa on the Black Sea. Some portions of the oil from Sangachal is also exported via a northern pipeline to the Russian Black Sea port of Novorossiysk. Tankers are used to ship the crude from Supsa and Novorossiysk.
Central Azeri platform
The Central Azeri is an offshore PDQ platform located in approximately 128m of water, 100km east of Baku in the Caspian Sea. The Central Azeri facilities include: a 48-slot PDQ platform; a 30in oil pipeline from Central Azeri to the Sangachal Terminal; a 28in gas pipeline from Central Azeri to the Sangachal Terminal; and the expansion of the existing onshore terminal at Sangachal.
Production from the Central Azeri field began in February 2005 under phase I of the development. This comprised two platforms built at the Amec-Tekfen-Azfen (ATA) yard, one for production and the other for compression and to provide water injection services to the Central, West and East Azeri platforms. The total capacity for the platform is 420,000bpd.
West Azeri platform
West Azeri came onstream in 118m of water in December 2005 with three predrilled wells. It is situated in 118m of water. The West Azeri facilities include a 48-slot PDQ platform and a 30in oil pipeline connecting to the expanded onshore Sangachal terminal.
Associated gas from West Azeri flows via subsea pipelines to a Central Azeri compression and water injection platform for reinjection to ensure pressure maintenance or to be used as fuel. Surplus gas will be exported to the Sangachal terminal.
East Azeri platform
East Azeri is an offshore 48-slot PDQ platform located 100km off the Baku coast in the Caspian Sea.
“The ACG oilfield contains 5.4 billion barrels of recoverable oil.”
This platform has been in operation since 2006 with production capacity of 800,000bpd.
The Dada Gorgud completed the eight-well pre-drilling programme in December 2005. These are tied back to the platform once they are installed offshore.
The East Azeri topsides construction was carried out at the Baku Deepwater Jackets Factory (BDJF) yard, with all of the modules and the drilling derrick installed onto the integrated deck.
Gunashli field platform
Deepwater Gunashli (DWG) complex is the third phase of development of the ACG field in the Azerbaijan sector of the Caspian Sea. ACG field reserves expected to be produced during the PSA period are approximately 1.25 billion barrels.
The first oil from DWG complex was received on 20 April 2008. On plateau, the DWG complex will produce approximately 320,000bpd, thus bringing the total ACG production rate to a level of over a million barrels a day.
The DWG complex is located in a water depth of 175m on the east side of the Gunashli field. The complex comprises two bridge-linked platforms, a 48-slot drilling, utilities, and quarters (DUQ) platform, and a process, gas compression, water injection and utilities (PCWU) platform.
Production export off the complex is via two 30in oil pipeline tie-ins and a single 28in gas pipeline tie-in into pre-installed pipeline junctions located on the Azeri field subsea export pipelines to the onshore Sangachal terminal.
Uniquely, three subsea water injection wells have been installed in the DWG development. Production from DWG will be boosted by subsea water injection intended to ramp-up oil production by increasing pressure through injecting seawater into DWG reservoir.