Abu Dhabi - The Gas Sector & OGD 1-2 Projects.

Total gas production capacities in Abu Dhabi rose from 1.8 BCF/day in 1992 to more than 4 BCF/day by August 1996. A major part of the production is associated gas, which will be fully utilised by 2001 compared to 89% in 1992. Most of the onshore gas supplies go to GASCO which has a major gas liquids complex at Ruwais. Most of the offshore gas goes to the LNG export complex on Das Island. The SPC, ruling over the hydrocarbon sector, decided in 1991 to launch ADNOC's Onshore Gas Development (OGD) programme, to cost about $2 bn, based on developing Thamama gas at the Bab and Asab fields and ADCO's other structures close to the Habshan area. This was prompted by rising demand, both for domestic gas consumption and for export in liquid form. Development of Bab gas, called OGD-1 or Project 545, has cost $1.35 bn. It was completed in August 1996. The main contracts were awarded in March 1993 and June 1994 to a consortium of Technip of France (40%), Bechtel of the US (30%) and Athens-based Consolidated Contractors Co. (30%). The project manager was Brown & Root of the US, with supervision done by a projects unit at ADNOC on ADCO's behalf. Completed in November 1996, OGD-1 raised output and processing at Habshan from 540 MCF/day to 1,865 MCF/day. It raised to 131,000 b/d the condensate recovery rate, from 5,000 b/d, with most of the condensates to be exported until the condensate units at the Ruwais refinery have been built (see DT). OGD-1 involved the following: (1) non-associated gas develop from the Thamama C and F reservoirs, beneath the field's oil reservoirs, and associated gas from Thamama B; (2) two new trains at the Habshan gas treatment complex, each with a capacity of 350 MCF/day, to process associated and non- associated gas; (3) another new train at Habshan, with a capacity of 625 MCF/day, to process non-associated gas from Thamama F into NGLs and condensates; (4) a new gas compression station for Thamama B in an area 5 km from Habshan; (5) two new gas injection trains which raised capacity from 280 MCF/day to 1,100 MCF/day for the dry sour gas for injection into the F reservoir; (6) facilities for dry gas to be processed into LPG and for power plants; (7) condensate storage and transfer facilities, consisting of six 430,000-barrel tanks at Ruwais, 105 km from Bab, and two 195,000-barrel tanks at Habshan; (8) three sulphur recovery units of 600 t/day each; and (9) 245 km of pipelines with diameters ranging from 10 to 30 inches. About 830 MCF/day of the gas goes for domestic consumption. The second phase, OGD-2, to cost $1.4 bn, was in April 1998 awarded to the Technip/Bechtel partnership, with CCC as sub-contractors. It calls for the development of Thamama C North & South and Thamama D of the Bab and Habshan structure and the drilling of 52 wells to extract 1,100 MCF/day of gas, which will be processed at Habshan for production of 55,000 b/d of condensate, about 500 t/y of NGL, and 2,100 t/d of sulphur. The project should be completed by late 2000. The front-end engineering and design contract was awarded in June 1996 to Technip. In mid-October 1998 Snamprogetti got the $110m contract for OGD-2's gas gathering system involving 300 km of flowlines and construction of a receiving terminal. An important part of the gas will be for domestic consumption. A related $150m gas pipeline from Bab to Maqta and the new Taweelah-B power station, known as Project 1,204, has been completed. This involves a 42-inch, 125 km pipe from Bab to Maqta and a 36-inch, 57 km pipe from Maqta to Taweelah. To increase the sulphur handling capacity for its OGD system, called Project 1205 and costing $15m, ADNOC awarded the contract in 1994 for completion before end-1994. Pritchard Corp. did the front-end engineering design. OGD-2 will turn Habshan into one of the world's largest gas processing plants with total gas treatment capacity of almost 3 BCF/day. The related Asab gas development project (AGD), to cost about $700m, was awarded in July 1997 to Snamprogetti. To be completed by end-1999, this involves the drilling of wells to extract 856 MCF/day of wet associated gas from Thamama F and G formations under Asab's oil reservoirs, plus about 80,000 b/d of condensates to be stripped out and the remaining dry gas to be reinjected into the reservoirs to maintain field pressure; a gas gathering and injection pipeline; and related facilities. Pritchard has done AGD's front-end engineering and design. Willbros Engineering did the designs for the pipeline under a sub-contract. ADCO in May 1993 had contracted Babcock Engineering to install a system to inject gas into the North Shuaiba reservoir by end-1995, with management and front-end engineering design done by Bechtel. It also awarded a contract for a gas gathering network from Thamama C and F to link up with ADNOC's OGD in 1996. This project cost $150m, with Bechtel as consultant. Brown & Root provided the front-end engineering and design.