LNG processes and technology

The Optimized Cascade^® Process – proven technology

Australia Pacific LNG's LNG facility will be located on Curtis Island off the coast of Gladstone in Queensland. Joint venture partner ConocoPhillips is responsible for the construction and operation of the Project's LNG facility.

ConocoPhillips' proprietary Optimized Cascade^® technology is a proven and reliable technology well suited to a CSG to LNG application. On arrival at Curtis Island, the Process will be used to liquefy the coal seam gas.

Explore the Optimized Cascade^® Process

How CSG is converted into LNG

The raw gas is first treated to remove the typical contaminants, mainly water and carbon dioxide before being delivered to the liquefaction section of the plant. There, the treated gas is chilled, cooled and condensed to minus 161 degrees celsius in successively colder heat exchangers, using propane, ethylene and methane as refrigerants. The LNG product is then pumped into insulated storage tanks where it remains until shipment.

Gases that boil out of the LNG as it warms slightly in the storage tank are captured and returned to the process for re-liquefaction, minimising product losses.

ConocoPhillips is continuously improving this process to increase thermal efficiency, reduce emissions and reduce the life-cycle cost.

Find out more at ConocoPhillips LNG technology licensing

How LNG is stored

On land, LNG is stored at atmospheric pressure in specially engineered and constructed double-walled storage tanks. Most of these tanks have 90cm concrete exterior walls and an inner tank that is constructed from a steel-nickel metal alloy specifically designed to keep LNG cold.

Sophisticated monitoring systems provide constant surveillance for internal leaks.

Explore the LNG process fact sheet