Alcoa develops carbon capture for aluminum plants

Alcoa (NYSE: AA), the world's leading producer and manager of aluminum, announced a new technology today at an alumina refinery in Western Australia for capturing carbon emissions.

Alcoa’s in house-developed system is a treatment process that involves mixing bauxite residue, a by-product of the aluminum-making process, with carbon dioxide (CO2).

The company says the process 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, the company said today at a conference in New York.

Alcoa plans to deploy the technology at its nine alumina refineries worldwide. Deployment across Alcoa’s operations in Australia alone is expected to save 300,000 tons of CO2 each year.

The 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. 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, a move which it called "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. The company 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 is calling on the U.S. government to quickly enact strong national legislation to achieve significant reductions of greenhouse gas emissions.

Alcoa has 122,000 employees in 44 countries.

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