NWSSSC - NWS project

north west shelf project

The North West Shelf Venture has an enviable reputation as one of the region's most reliable producers and suppliers of natural gas.

The North West Shelf Venture is Australia's largest resource project with investment in onshore and offshore oil and gas facilities totalling more than A$14 billion.

The venture is a major producer of liquefied natural gas (LNG), natural gas, liquid petroleum gas (LPG), condensate and crude oil, and accounts for more than 40% of Australia's oil and gas production.

Venture facilities include two fixed offshore platforms (North Rankin and Goodwyn), one floating production, storage and offloading vessel (Cossack Pioneer), and Australia's largest onshore gas plant.

The onshore gas plant includes four LNG processing trains, a natural gas plant to supply Western Australia, LPG and condensate production facilities, and storage and loading facilities for LNG, LPG and condensate.

The offshore and onshore facilities are linked by two subsea pipelines, proving a flexible operating system and reliable gas supply.

Operations cover five major oil and gas fields in 11 permits, one of which - North Rankin - has been in production for 20 years.

The North West Shelf Venture operates four LNG processing trains with a capacity of 11.7 million tonnes of LNG a year. The NOrth West Shelf Venture is further expanding its LNG facilities, including the construction of a fifth train with a capacity of 4.2 million tonnes of LNG a year and extension of loading facilities. First LNG from the expanded operations is expected in Q4 2008.

Key elements of each LNG train include the sulphinol units, which remove carbon dioxide from the gas; dehydration units for removal of water; a mercury removal unit; a scrub column, which removes the heavier gases; a liquefaction unit, which reduces the temperature of the gas from minus 35ºC to minus 130ºC; and two end flash vessels, where a reduction to atmospheric pressure leads to further cooling, achieving the cold temperature boiling point for methane of minus 161ºC. At this point, the gas condenses to a liquid at 1/600th of its gaseous volume.

The LNG is then stored in one of four heavily insulated storage tanks, each with a capacity of 65,000m³, before being piped to the LNG jetty for offloading onto purpose-built LNG carriers for transport to Japan and other international markets.