PILOT EXPERIMENTS OF LOW TEMPERATURE (700 ～ 800°C) ALUMINUM ELECTROLYSIS IN A 5KA ALUMINUM REDUCTION CELL

摘要

In this paper, pilot experiments of the new technique of low temperature (700 ～ 800°C) aluminum electrolysis in a 5kA aluminum reduction cell are conducted. The electrolyte is the Na_3AlF_6-AlF_3-BaF_2-CaF_2 bath system. The experiment results indicate that the Na_3AlF_6-AlF_3-BaF_2-CaF_2 bath system is promising. These pilot experiments lay a good foundation for industrial application. In the meantime, the physico-chemical properties of Na_3AlF_6-AlF_3-BaF_2-CaF_2 CaF_2 bath system were systematically studied based on experiments designed using three-factor quadratic orthogonal regressive method. The cathodic current efficiency (CE) of the new low temperature aluminum electrolysis is up to 94% and DC power consumption 12000kWh/t aluminum in 5kA experiment cell.