ALUMINIUM SLAG PROCESSING Russian patent published in 2014 - IPC C22B7/04 

FIELD: process engineering.

SUBSTANCE: invention relates to processing of aluminium slags. Proposed method comprises processing of aluminium slags in electroslag furnace including crucible with bottom cathode and top anode. Cryolite (Na₃AlF₆) and aluminium oxide (Al₂O₃) are fed into said crucible and fused therein. Then, crushed aluminium slag, a mechanical mix of Al₂O₃ and aluminium metal, and cryolite are loaded in electrolyte liquid melt with subsequent melting and dissolution in electrolyte. Note here that melting and dissolution of aluminium slag occur at 1100-2000°C. Precipitation of liquid aluminium metal occurs in the area of bottom cathode. Note that precipitation of liquid secondary slag composed of the mix cryolite with aluminium oxide occurs in the area of anode. Thereafter, aluminium and secondary slag are unloaded.

EFFECT: almost complete separation of aluminium slag metal fraction and oxide fraction, up to 99% extraction of aluminium.

3 cl, 1 dwg