Validation of PFC Slope at Alcoa Canadian Smelters with Anode Effect Assessment and Future Implications to Add Low Voltage Emissions into Total PFC Emissions

Climate change challenge leads government to commit themselves to a greenhouse gas reduction target and to adopt Greenhouse gas (GHG) regulation including sampling and monitoring. By regulation, all the aluminum smelters in Quebec using the slope method must validate its PFC slope at least every 36 months. This is required even more often if a change occurs in the control algorithm that affects the intensity or duration of the anode effects or when a change occurs in the distribution or duration of anode effects. The three aluminum smelters operated by Alcoa located in Quebec have implemented an anode effect assessment, which includes, among others, pot start anode effect data and reviews of the distribution of anode effect duration. With the analysis of the monitoring data obtained from the anode effect sampling of pot starts, as well as with high and low voltage anode effect measurements it is the objective to seek more accurate PFC slope determination for better reporting purposes.