The feasibility study - called operability and vulnerability of trains 1 and 2 - is aimed at carrying out a techno-economic analysis of the ageing LNG production units and also evaluating the best available technology for a new LNG train. The six-month contract will be carried out in two phases.

Phase 1 will include suggesting options for assessing the remaining life of the two existing trains and their rejuvenation. The second phase will cover the feasibility of replacing both LNG trains with a single mega train. Adgas has suggested a base capacity option of 5 million tonnes a year (t/y) and an alternative option of up to 8 million t/y.

Adgas owns and operates the Das liquefaction plant comprising three trains, with total design capacity of 3.5 million t/y. However, through extensive debottlenecking, the trains produce a total of 6 million t/y of LNG, as well as about 1.7 million t/y of liquefied petroleum gas (LPG), 535,000 t/y of pentane and 338,000 t/y of sulphur. Trains 1 and 2 were commissioned in 1977; train 3 started production in 1994.

In September, Adgas issued a letter of intent to Pakistan's Descon Engineering for an estimated $30 million-35 million, three-year maintenance contract covering its liquefaction plant (MEED 7:10:05). The contract is scheduled to start in 2006, and will be for trains 1, 2 and 3. Bids are due to be submitted on 8 November for the estimated $15 million engineering, procurement and construction (EPC) contract to upgrade filtration systems and related facilities at the three LNG trains.

Established in 1973 to convert gas extracted from Abu Dhabi's offshore oil fields, Adgas is a joint venture of Abu Dhabi National Oil Company (ADNOC - 70 per cent), Mitsui & Company of Japan (15 per cent), the UK's BP (10 per cent) and Total of France (5 per cent).