Continuous PFC emissions measured on individual 400KA cells

Abstract

PFC emissions from the primary aluminium industry have traditionally been linked to anode effects (AE), which are most broadly defined as when the voltage on a cell exceeds 8 Volts for more than 3 seconds. Recent studies however have revealed the existence of continuously generated PFCs, which are not related to a conventionally defined AE. In a study focusing on individual 400kA cells, the continuous generation of PFCs was measured on several pots, was found to vary from one cell to another, and to vary within a number of hours. Generation of these PFCs also varied from one localised region to another within a cell and may be linked to instabilities in local current distribution, as suggested by 20Hz continuous monitoring of individual anode currents. While the study provides further understanding on the characteristics of these PFCs, further work is required to determine the fundamental causes of this emission.