SBIR Phase II: Barrier Centrifuge for Aluminum Purification

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase II project is in reducing the environmental impact of Aluminum production. Global production of aluminum from bauxite ore currently accounts for 1% of global electricity consumption, and 2.5% of CO2 emission. Over the last 15 years global production has doubled, and is expected to continue to increase over the next decades with expanded use in automotive applications. To meet increasing demand while reducing the environmental impact of production requires cost effective means of removing contaminating metals such as iron from aluminum. Commercial application of the technologies investigated here would positively affect the global aluminum industry and reduce its environmental impact. Applied to conventional primary production, the technology can be used to increase the yield from bauxite, or allow kaolinite clays to be used for primary production. The former will reduce the environmental and economic costs of production, while the latter would allow domestic producers to reduce their reliance on imported bauxite. If the technology is applied to primary production using carbothermic reduction, the impacts on the global aluminum industry would be even greater. Greenhouse gas emissions could be reduced by up to 50%, and electricity consumption reduced by up to 20%. The objective of this Phase II SBIR research is to demonstrate a cost effective barrier centrifuge technology to remove contaminating elements from aluminum alloys. In the Phase I research we demonstrated the basic technology using a liquid gallium alloy instead of aluminum. In Phase II, we will fabricate an apparatus for handling liquid aluminum and characterize its purification efficiency and costs to own and operate. Using the barrier centrifuge to purify aluminum in secondary production would reduce the need for dilution by primary aluminum, thereby reducing the demand for the primary aluminum with a consequent reduction in electricity consumption, greenhouse gas production and waste disposal needs from the bauxite refining process.