Otway basin CO₂ sequestration trial advances

MELBOURNE, Feb. 27 -- Australian Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC), Canberra, has been awarded two production licenses in the onshore Otway basin of western Victoria in which to conduct its first carbon dioxide sequestration trial.

Subject to environmental approvals, the pilot gas injection, storage, and monitoring program will begin by yearend.

CO2CRC is now 100% owner of licenses PPL11 and PPL13, which cover Buttress CO2 field and nearby depleted Naylor natural gas field.

The program will involve production of CO2 from Buttress at a rate of 3 MMcfd, piping the gas 1.75 km to Naylor, and injecting it into the Cretaceous Waarre reservoir on the flank of the depleted field via a well to be drilled this year.

Injection will continue for about 2 years.

Monitoring has begun in the region to establish baseline data and will continue for the next 4-5 years to gauge the movement of CO2 in the reservoir. A number of monitoring points will be established within a 5 sq km area around the injection point. There will also be monitoring equipment in the old Naylor-1 well.

Buttress reserves exceed 10 bcf, 90% CO2. The minor amounts of methane will be stripped out and used to power the compressors and other equipment.

The Otway Project is believed to be the only one in the world where researchers own the petroleum leases, the CO2 source, and the depleted storage reservoir.

The Victorian government has allocated $4 million (Aus.) to the program. Funding also is coming from petroleum companies and overseas research groups. About 30 researchers will be involved in the project.

Results will be particularly relevant to the proposed Gorgon gas project off Western Australia, which is to inject that field's 12% CO2 content into reservoirs under Barrow Island when it comes on stream in 2010-11.