COMBUSTION/VITRIFICATION TREATMENT OF SPENT POTLINING

PROPOSED RESEARCH WILL ESTABLISH THE TECHNICAL FEASIBILITY OF A COMBINED COMBUSTION/VITRIFICATION PROCESS FOR THE TREATMENT AND DISPOSAL OF SPENT ALUMINUM POTLININGS. RE- SEARCH RESULTS WILL BE EVALUATED AGAINST PREDETERMINED CRITERIA TO VERIFY THE TECHNICAL FEASIBILITY OF THE PROCESS. SPENT ALUMINUM POTLININGS ARE PRIMARILLY GRAPHITIZED CAR- BON AND REFRACTORY MATERIALS, CONTAINING FLUORIDE, ALUMINUM SODIUM AND CYANIDE. THE POTLININGS EXHIBIT SEVERAL CHARAC- TERISTICS OF HAZARDOUS WASTES. NO SATISFACTORY DISPOSAL TECHNOLOGIES EXIST AT THIS TIME. THE AWV COMBUSTION/VIRTIFICATION PROCESS INVOLVES COMBUS- TION 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 PROD- UCT. CRITERIA THAT ESTABLISH TECHNICAL FEASIBILITY INCLUDE:(1) ABILITY OF POTLININGS TO SUPPORT COMBUSTION AND SLAGGINGCONDITIONS, (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 EXISTINGALUMINUM REFINERY OFF-GAS TREATMENT SYSTEMS. IT IS ANTICIPATED THAT THE PROPOSED RESEARCH WILL ESTAB- LISH THE TECHNICAL FEASIBILITY OF THE AWV PROCESS FOR TREAT-MENT AND DISPOSAL OF SPENT POTLININGS. THE PROPOSED RE- SEARCH WILL PROVIDE THE BASIS FOR OBTAINING INDUSTRY PARTIC-IPATION AND FUNDING FOR FUTRHER DEVELOPMENT TO PROVIDE ECO- NOMIC FEASIBILITY, AND TO PROVIDE A DESIGN BASIS FOR PROTO- TYPE DEMONSTRATION AND EVENTUAL COMMERCIALIZATION OF THE PROCESS