First trials prove a success in capturing carbon dioxide

Australian
Thursday 10/7/2008 Page: 2

AUSTRALIA has conducted its first successful trials of the leading technology for capturing climate warming carbon dioxide from a coal-fired power plant. Using the technology known as post-combustion capture (PCC) a team of industry technicians and CSIRO researchers successfully removed more than 80 per cent of the CO2, from the exhaust-gas flues of a pilot power plant in Victoria's Latrobe Valley. News of the trials at Loy Yang power station, which began last month, came yesterday at a meeting of scientific and industry experts at the Gippsland campus of Monash University.

Isolating CO2, is the first step in a process known as carbon capture and geosequestration, an emerging technology designed to reduce CO2, emissions from gas and, critically, highly polluting coal-fired power plants. CSIRO energy technology chief David Brockway said: "Coal is the primary fuel for over 80 per cent of Australia's current power supply.

It's what turns the lights on in most homes, so we need to find ways to make it a cleaner energy source." In PCC, flue gas is cooled and cleaned, then fed into a cylinder containing a liquid that absorbs the CO2,. The cleaned flue gas, mostly 100 per cent nitrogen, is released into the atmosphere. In the trials, the CO2 was also released, but commercial plants would compress and cool it to form a liquid to be sequestered.

Although trials of PCC are ongoing in Canada, the US, Europe and Japan, Dr Brockway claimed Australia was not lagging behind. Dr Brockway, a chemist specialising in combustion and gasification, Australia's challenge was greater than that of the rest of the world because Australian plants are older and dirtier. "Others already have (pollutants like) nitrogen oxide and sulphur dioxide removed." Because systems to remove these pollutants are expensive, Dr BrockWay said the team devised a method of eliminating them, too.

Queensland University chemical engineer Paul Massarotto said it might be possible to sidestep capture: "We wouldn't have to capture the flue gas first." Along with UQ colleagues, Professor Massarotto announced yesterday he had joined Chinese researchers to develop a pilot project to pump greenhouse gas emissions directly into underground coal seams.

According to Dr Brockway, the key to effective PCC is tailoring the mix of flue gases with the absorber. Most systems use different forms of aqueous amines. The PCC project will trial several at Loy Yang and pilot plants to be commissioned at Munmorah on the NSW central coast, in Beijing and in Queensland. The Loy Yang trials are part of the Latrobe Valley PCC Project, a collaboration between Loy Yang Power, International Power Hazelwood, state and federal governments, the CSIRO and the CO2CRC