Proposed research will establish the technical feasibility of a combined combustion/vitrification process for the treatment and disposal of spent aluminum potlinings. Research results will be evaluated against predetermined criteria to verify the technical feasibility of the process. Spent aluminum potlinings are primarily graphitized carbon and refractory materials, containing fluoride, aluminum, sodium and cyanide. The potlinings exhibit several characteristics of hazardous wastes. No satisfactory disposal technologies exist at this time. The AWV combustion/vitrification process involves combustion of carbon, recovery of fluoride for reuse, destruction of cyanides, and vitrification of metals and glass formers to produce a non-leachable glass matrix or marketable product. Criteria that establish technical feasibility include: (1) ability of potlinings to support combustion and stagging conditions, (2) ability of product melts to be sustained by joule-heating, (3) acceptable recovery of fluoride as HF, (4) production of a non-hazardous waste vitreous product, (5) production of no secondary hazardous wastes, and (6) suitability of process off-gas for treatment in existing aluminum refinery off-gas treatment systems. It is anticipated that the proposed research will establish the technical feasibility of the AWV process for treatment and disposal of spent potlinings. The proposed research will provide the basis for obtaining industry participation and funding for further development to provide economic feasibility, and to provide a design basis for prototype demonstration and eventual commercialization of the process.
