Monitoring CO2 storage in Australian gas field
Australia has launched the first carbon sequestration project in the southern hemisphere with the help of technology developed by researchers at the US Department of Energy (DOE). The Otway Basin Pilot Project will inject and monitor carbon dioxide (CO2) in a depleted gas field in south-eastern Australia to demonstrate the feasibility of storing the greenhouse gas in the Waarre Formation of the Otway Basin, and similar formations worldwide, to fight global climate change. The $36 million Otway Basin Pilot Project is one of 19 sequestration projects endorsed by the Carbon Sequestration Leadership Forum (CSLF), an international climate change initiative that focuses on the development of technologies to cost-effectively capture and sequester CO2. The project is directed by Australia's Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC). Project partners include DOE and a variety of other public and private organizations.
Up to 100,000 metric tons of CO2 will be injected more than a mile beneath the earth's surface. A team of Australian, American, and other international researchers will monitor the storage reservoir before, during, and after the CO2 is injected. The injection process will span 1 to 2 years, while monitoring and modeling activities will last for several years beyond that.
The Otway Basin is an excellent test site because it has a large source of natural CO2 and an abundance of now-depleted gas fields containing rock formations with a geologic history of storage permanence. CO2 will be produced from an existing well, then compressed to a supercritical state to more efficiently move and store it at a final location.
Once the CO2 has been transported and injected, comprehensive monitoring and verification will take place to demonstrate that long-term storage is viable. According to CO2CRC Chief Executive Peter Cook, 'A key feature of the project is that it is one of the world's most comprehensive subsurface carbon dioxide monitoring programs ever undertaken, and it was designed, developed and implemented by CO2CRC researchers from Australia, New Zealand, the USA and Canada.'
In research sponsored by the Office of Fossil Energy's National Energy Technology Laboratory (NETL), the Lawrence Berkeley National Laboratory (LBNL) developed cutting-edge instrumentation that will be used to track the CO2 plume during and after the injection. Sophisticated seismic techniques will provide data about the location, migration, and permanent storage of the CO2 plume, which will be more than a mile deep.
Remote sensing is just one of several monitoring techniques LBNL researchers will deploy from a toolbox of recent advancements. Another technique is a unique formation well sampling method that taps the reservoir and delivers fluid samples to the surface for determination of CO2 content and other geochemical analyses. Using geophysical, geochemical, and other reservoir data acquired during storage operations, the researchers will also be able to refine models to significantly increase the predictability of formations to permanently store CO2.
Lessons learned from the Otway project can be applied elsewhere in Australia, the United States, and worldwide. With support from NETL, LBNL researchers transfer sequestration technologies by participating in several international CO2 storage demonstrations on other continents, including CO2SINK near Berlin, Germany, and the commercial-scale CO2 storage operations at In Salah, Algeria.