May 16 2007
Alcoa has announced that it has launched a new technology at its Kwinana alumina refinery in Western Australia that has the potential to deliver significant global greenhouse benefits and will contribute to a reduction in the aluminum industry's environmental footprint. Alcoa announced the new technology in conjunction with its sponsorship of the C40 Large Cities Climate Summit taking place this week in New York City. During the four-day summit, leaders of municipal governments and international businesses will share best practices, identify collaborative projects and chart future actions related to reversing climate change and realizing economic development benefits.
Alcoa's 'Carbon Capture' system is an innovative residue treatment process that involves mixing bauxite residue, a by-product of the aluminum-making process, with carbon dioxide (CO2). This delivers greenhouse benefits by locking up large volumes of CO2 that would otherwise be released to the atmosphere. The Kwinana carbonation plant will lock up 70,000 tons of CO2 a year, the equivalent of eliminating the emissions of 17,500 automobiles. As part of its on-going commitment to reduce its global emissions, Alcoa plans to deploy the technology to its nine alumina refineries worldwide. Deployment across Alcoa's operations in Australia alone could potentially save 300,000 tons of CO2 each year.
The 'Carbon Capture' system was developed by Alcoa's Technology Delivery Group, the company's global refining research and development unit, which is based in Australia. Bauxite residue is a mixture of minerals that are left behind when alumina is removed from bauxite. Although it is thoroughly washed, the residue retains some alkaline liquor and requires long-term storage. By mixing CO2 into the bauxite residue, its pH level is reduced to levels found naturally in alkaline soils. A second sustainability benefit is that the improved environmental properties of the residue mean it also can be beneficially used as road base, building materials or to improve soil. Alcoa plans to share the technology within the aluminum industry which is also vital to its long term sustainability.
Alcoa has taken a leadership position on climate change by reducing its global greenhouse emissions by 25% compared to 1990 levels seven years before the 2010 deadline. Alcoa is also a founding member of the U.S. Climate Action Partnership (USCAP) an alliance of nine major U.S.-based companies and four leading environmental organizations that has taken the public lead in calling on the U.S. government to quickly enact strong national legislation to achieve significant reductions of greenhouse gas emissions.
http://www.alcoa.com