Restart of Copper-Insert Pots in EGA’s High Amperage Potlines

Abstract

Good performance in pot preheat, start- up and early operation is key for pot life in long run. However, instances may be encountered where few pots might need to be cut out earlier than expected potlife due to power outage or to abnormal pot condition in early operation or later. Copper-insert collector bars have become a requisite for lining design to improve energy efficiency. Restart experience of copper-insert pots is different than of pots with conventional steel collector bars. Experience in start-up of copper-insert pots is captured in detailed systematic procedures, such as collector bar resistance measurement, taken on cavity cleaned cathode, and pot restart economic study estimating the cost of restart and expected pot life to payback. Procedures detailing the activities and parameter changes required during pot cut-in, preheat control and stabilization period during early life are presented in this paper.