Alcoa (NYSE:AA) announced on Tuesday that it has launched a new carbon capture 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’s Carbon Capture system is a in house developed 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. Alcoa plans to deploy the technology at its nine alumina refineries worldwide. Deployment across Alcoa’s operations in Australia alone could potentially save 300,000 tons of CO2 each year.
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.