Study on the process of separating electrolyte from aluminum electrolytic spent carbon anode by flotation

The spent carbon anode (SCA) produced by electrolytic aluminum plants contains a large amount of fluoride salt electrolyte, which is harmful to the enterprises, environment and society. At present, the solution strategies of SCA produced by electrolytic aluminum plants mainly include flotation, roasting, vacuum smelting, fluidized bed technology and safe landfill, but only the flotation method does not produce toxic and harmful substances which is a relatively clean treatment method. However, in the past, the focus of flotation treatment of SCA was to separate and purify the carbon of SCA to obtain high-purity carbon as recarburizer, battery anode material or fuel, which is a waste of the separated electrolyte. Therefore, the electrolyte in the SCA is recycled by the flotation method. The best flotation conditions are obtained through single factor experiment. Then, a new flotation process of one coarse and three sweeps are adopted to improve the purity and recovery rate of the electrolyte until it reaches the highest value. Thus, the electrolyte of treated SCA can be returned to the electrolytic aluminum plant to recycle or sell. Therefore, the harmlessness, resource utilization and reduction of solid waste are realized, and the social and economic benefits of the enterprise are improved with the utilization rate of SCA increased.