Review on the recycling of used cathode carbon blocks produced in aluminum electrolysis

The properties and disposal of used cathode, a toxic and hazardous waste produced in aluminum electrolysis, have been the research hotspots in recent years. In light of the research progress at home and abroad, the paper reviews the breaking causes and degree of cathode carbon blocks in aluminum electrolysis under different service time, and chooses reasonable preventive and repairing measures according to the breaking causes. It also analyzes the breaking degrees of different layers of used cathode in the same aluminum electrolytic cell in order to classify and better dispose of cathode carbon blocks in the later research process. After that, a brief introduction has been made to their disposal in aluminum electrolysis at home and abroad, such as the flotation method, chemical method and high temperature method, and the advantages and disadvantages of some representative disposal processes. It concludes with a summary and anticipations on their recycling.