Thermal behavior of prebaked aluminum reduction cells: Modeling and experimental analysis

Finite difference technique has been used to construct mathematical model that has been used to study the thermal aspects of high-amperage end to end prebaked aluminum reduction cells. The influence of the ambient temperature (T-a) and the convective heat transfer coefficient at the shell/air interface (h) on the ledge profile. bath temperature and temperature distribution within the solid phases of the cell has been determined using this model. The total energy balance of the cell has been analysed. It has been found that as h increases the ledge gets thicker: the change in T-a mainly affects the bath temperature. No significant effect of h on the bath temperature has been observed. These results of the model compares favorably with field measurements on six Ni scale prototype pre-baked cells (200 kA), constructed and operated by the Aluminum Company of Egypt. at Nage Hammady. where ambient temperature ranges between 5 degrees C and 50 degrees C. Heat transfer coefficient changes between 2 and 10 W/m(2) degrees C pending on seasonal changes and the location of the cell.