New method for representative measurement of anode electrical resistance

Abstract

Anode electrical resistance is more and more recognized as a key parameter for pot operation, as the carbon material itself contributes close to 50% of the anode assembly voltage drop. Factors such as raw materials, forming and baking conditions are sources of significant variation in anode properties, including anode resistance. Anode resistance will vary within an anode and between anode batches, causing voltage differences up to several tens of millivolts. The current method for resistivity measurement is based on core sampling of a small number of anodes in limited locations and may not be representative of the global anode resistance. The current study proposes a non destructive method that reproduces the current distribution in service and provides immediate results. Such results could be used to improve anode resistance and help potrooms cope with anode batch variability.