Technology Research on Decreasing the Aluminum Surface Waves and Reducing the Cathode Voltage Drop in Aluminum Electrolysis Cell

The influence of the materials of cathode carbon block and cathode steel bar, cathode steel bar size and steel bar assembly way on the horizontal current of aluminum liquid and cathode voltage drop was studied using simulation calculation and industrial cell experiment. It is aimed to obtain the technical parameters for decreasing the longitudinal fluctuation of aluminum liquid and reducing the cathode voltage drop, increase the stability of electrolytic cell and realize the cells operated at low voltage and high efficiency. The results of simulation study and industrial cell tests show that it can effectively reduce the liquid aluminum surface waves and the cathode voltage drop through comprehensive optimization of cathode carbon block and steel bar materials, reasonable design of cathode steel bar size and optimizing steel bar assembly ways. The results of 350 kA test cell indicate that the cell voltages are about 3.82–3.85 mV at the current density of 0.73 A/cm2 and the cell voltages fluctuation range is about 6–8 mV. Starting after 180 days, the cathode voltage drop is about 190–220 mV. It realized high current efficiency of production under the condition of low voltage, and reduced the energy consumption for aluminum electrolysis production.