AP40: the latest of the AP Technology™ solutions

Another significant step in the AP30 development has been successfully demonstrated; one that further enhances productivity. After the AP39 technology validation, an enhanced operating point has allowed cells to operate above 400 kA without decrease in energy efficiency. Since July 2010, these cells, now referred to as AP40, operate at St Jean de Maurienne in the range of 400405 kA with specific energy consumption below 13150 kWh/t. Achieving this performance required an extensive review of operational aspects including busbar capability, operational quality, and process control. Also essential was the use of an "operating window" approach to determine the optimal operating point. By following a cell development methodology over two years, results have demonstrated a high level of process performance (anode effect frequency, current efficiency and energy consumption). Measurement campaigns have confirmed the excellent level of pot robustness.