‘Loneliest gas in world’ near production stage

Press, 8 January 1983, Page 4

‘Loneliest gas in world’ near production stage

Gas from Australia's biggest resource development, the SAustl 1,000 million North-West Shelf natural gas project, will start flowing ashore through a 134 km submarine pipeline in 1984. With the deadline nearing and investment running at sAust2 million a day. work is reaching its peak on the offshore production facilities and at the on shore treatment plant at Withnell Bay near Dampier on the northwestern coast of the continent.

The base for the first production platform, which will tower 100 metres above the Indian Ocean when topside modules are in place, has been secured to the seabed above the big gas reservoirs. The steel pipeline has also been positioned on the seabed to link the platform with Withnell Bav.

The project is a two-base development and will run for at least 20 years. The first phase, to produce gas for Western Australian markets by October. 1984. has passed the halfway mark and is on schedule, its cost is about 'SAust22oo million.

The second phase, costing sAustBBoo million, will produce liquefied natural gas (L.N.G.) lor ■ Japanese markets, from 1987. a vear

later than anticipated because of protracted sales negotiations.

The first gas will come on stream 21 years after exploration began on the North-West Shelf and 13 years after the discovery of gas trapped in sandstone reservoirs 3km beneath the seabed in water depths down up to 125 m. It has been described as the loneliest gas in the world. To reach the fields has presented an engineering challenge and to develop them has imposed a heavy financial budden which will not be rewarded until the full production stage towards the end of the decade. The benefits will be two fold, greatly increasing Western Australia's energy selfsufficiency and creating a new export in L.N.G. The natural gas. which will be used by industry in the Pilbara and in the southwest of the state as well as by householders, is expected ( to cut Western Australia's dependence on oil from more than 70 per cent-to 45 per cent. Almost 80 per cent of the state's oil needs are imported. mainly from O.P.E.C countries.

Main export industries of iron ore. alumina and nickel are among the potential

users of the 10.9 million cubic metres of gas the State Energy Commission will buy daily from the Shelf project partners. .

The S.E.C. has signed 20year contracts worth about sAust 10,000 million to buy the gas, which will be piped south to Perth and nearby industry through a 1500 km pipeline from Withnell Bay.

The new trade created by the export of the entire annual L.N.G. production of six million tonnes will rank with Australia's four leading export industries — coal, wheat, wool and iron ore —

as a foreign exchange earner.

The Shelf will also produce an annual average of 1.4 million tonnes of condensate (a light crude oil which condenses out of the gas stream during production) and 640,000 tonnes of liquefiedpetroleum gas (L.P.G.), further reducing dependence on imported liquid 'hydrocarbons.

The project partners expect to find a ready market for both products in Australia. with possibly a surplus of L.P.G. for export. All production initial!}' will come from the North Rankin field, one of several adjacent fields located on the Shelf by a consortium led bv Wood-

side Petroleum. Ltd. Other companies involved are BP. Shell. California Asiatic Oil. and the B.H.P. group of Australia.

North Rankin is the biggest of the fields with reserves of 244.000 million cubic metres of gas. Up to 34 wells will be drilled into the reservoirs from each' of two production platforms on North Rankin.

A third platform is planned in the 1990 s for the nearby Goodwyn field, where drilling has produced a promising oil flow as well as vast gas reserves. Onshore, work is under way on the sAustsoo million gas treatment plant, due to be completed by June. 1984. and to be followed by a sAust2soo million liquefaction plant on the 150 ha site bordering Withnell Bay.

A fleet of seven specialised tankers, costing sAustlBoo million and forming the second most expensive part of the project, will transport the L.N.G. to Japan.

Even while the- project takes shape. Woodside has not slackened the tempo of its exploration. Just over the horizon from North Rankin, drill rigs continue to seek and evaluate new deposits of gas.