The impact of cathode and collector bar designs on cell performance

摘要

Novel cathode and modified collector bar designs have been tested recently by the aluminium industry. These tests have shown interesting achievements in terms of specific energy consumption. The authors discuss the weaknesses and strengths of these designs on the basis of three-dimensional thermal, electrical and magneto-hydrodynamic modelling work. Some of the model predictions have been validated by in-situ measurements in test cells. A good cathode design helps to decrease the CVD and to even out the current density in the liquid metal. Conversely, certain highly structured cathodes can be critical for cell operation and can have short life, even more so if the cell productivity is high. If some basic concepts are valid for all smelters, the optimum solution depends on the local cost structure.