On 14 September, what is being claimed as the word’s first integrated carbon capture system, a CC demonstration project jointly owned by Mitsubishi Heavy Industries and US utility Southern Company, began underground injection of carbon dioxide (CO2) recovered from emissions from a coal-fired power generation plant.

The event marks an important milestone in the world’s first ICCS project for flue gas from a coal-fired power plant – which contains significant quantities of impurity. The operation is on a scale of 500 metric tons per day (mtpd). Based on the results, MHI expects to be able to provide a reliable system ahead of other companies in the field as well as contributing to the general effort to solve the global warming problem.

The demonstration project calls for the capture and compression of CO2 from the flue gas of a coal-fired plant by a CO2 capture facility built at Southern Company’s Plant Barry in Alabama, and its sequestration in a saline formation at a depth of 3000-3400 metres in the Citronelle Dome geologic structure, approximately 12 miles west of the plant. The sequestration aspect of the project is being conducted as Phase III of the Regional Carbon Sequestration Partnerships programme, a programme sponsored by the US Department of Energy aimed at reducing greenhouse gas emissions. The volume of CO2 injection, which got under way following approval by the Alabama state government, has been progressively expanded and now reached the full-scale target of 500 mtpd. In the project MHI is responsible for basic planning, engineering, core equipment supply, and provision of technology support during the demonstration operation.

CO2 capture demonstration test has been successfully carried out at the plant since June last year. The CO2 facility, which was built jointly by MHI and Southern Company, as well as being the first, is the world’s largest in scale, and exhibits CO2 recovery efficiency above 90%. It consists primarily of a flue gas scrubber, flue gas CO2 capture/re-generation system, CO2 compression machinery, and electrical components. For CO2 recovery the facility adopts the KM CDR process, which uses a proprietary KS-1 high-performance solvent for CO2 absorption and desorption that was jointly developed by MHI and the Kansai Electric Power Co. Compared with other CO2 capture technologies, says MHI, the KM CDR process uses significantly less energy.

MHI has already installed 10 natural gas-fired CO2 capture facilities currently in operation, plus one under construction, for chemical plant applications. In the area of CO2 recovery from coal-fired plant flue gas, the company, working with the Research Institute of Innovative Technology for the Earth (RITE) and Electric Power Development Co., Ltd. (J-POWER), has already completed small-scale demonstration testing at 10 mtpd and confirmed uninterrupted stable operation. Through participation in the Barry project, MHI intends to show the high-level economic feasibility and reliability of its technology in the commercial-scale CO2 capture from coal-fired power plant flue gas, and to bring about its commercialisation.