The Impact of the Cavity on the Top Heat Losses in Aluminum Electrolysis Cells

The primary aluminum producers are continuously raising the line amperage to increase the productivity. Hence, the top heat losses of aluminum electrolysis cells are amplified which leads to higher thermal constraints on the anode cover. A finite element model is developed in order to predict the heat fluxes and temperatures in the top parts of the cell. The model is validated against measurements from the top surfaces of real industrial cells. It considers the cavity above the liquid bath, which is formed during the melting and falling of anode crust during the life of the anode. The heat flux escaping the anode cover increases with the height of the cavity according to the results. Considering the cavity inside the model is mandatory in order to obtain a good correspondence between the measurements and the model predictions.