Ra-400 technology development: a new balance between productivity and energy efficiency

摘要

Operation of aluminium smelters in modem market conditions requires achieving the highest production figures, which is impossible without a modem technology base.Over the last four years, experts of RUSAL United Company have performed extensive work to improve the power efficiency of modem high-current technologies used by RUSAL including the RA-400 technology.These works included testing of different approaches and evaluation of their efficiency when applied on commercial scale.The main areas of research included testing of the following options: 1.Decrease of amperage and ensuring the acceptable thermal balance (reduction of thermal losses) by adjusting the process parameters of electrolysis cells operation without changing the design of cells.2.ACD reduction and ensuring the acceptable level of performance indicators by improving the operating practices.3.Maximum increase of the size of anode blocks/ decrease of anode current density along with some increase of amperage to improve the productivity and compensate the thermal balance of cells operation at a decreased voltage.The effect of different options is described below, while the following results have been achieved: Amperage was increased from 425 to 440 kA.Cell productivity was increased by more than 100 kg/day.Cell voltage was decreased by more than 120 mV.Electric power consumption was decreased by ＞ 400 kWh/t.