Carbothermic production of aluminium

Abstract

In a process for the treatment of fume-laden carbon monoxide evolved in carbothermic reduction of alumina the fume-laden gas is contacted with particulate carbon in a fluidized bed maintained at a temperature, preferably in the range 2010.degree.-2050.degree. C. and above that at which sticky aluminium oxycarbide forms. The temperature of the bed is most conveniently controlled by the rate at which fresh carbon feed material is added to the bed. The hot gas emerging from the bed is rapidly chilled to a temperature below the solidification point of aluminium oxycarbide. This is most conveniently achieved by contact with a large excess of cool alumina/carbon mix in a stream which is continuously circulated through a heat exchange stage.

Dependencies are inferred from the claim text.