| Abstract Scope |
Anode changing, a major production operation in aluminum electrolysis, is the primary cause of zone anode current fluctuations in reduction cells, significantly reducing the zone’s anode current. As the new anode heats up and participates in electrochemical reactions, the zone current gradually recovers. During recovery, the zone anode current curve may show one or more of three stages: linear, steady, and step-up. The steady stage likely stems from slow dissolution of solidified electrolyte on the new anode surface, while the step-up stage (≈6.2 kA) mostly results from anode changing in an adjacent zone. Anode current recovery in the anode change zone falls into three modes. Among them, the linear-based mode (about 35 %) is the most ideal recovery mode, and the determination coefficient R2 of linear fitting for the recovery curve is ≥0.8; the steady-based mode (about 23 %) includes a steady stage in addition to a linear stage; the step-up-based mode (about 42 %) includes one or more step-up stages, and more than 75 % of the step-up-based curves also include a steady stage. These characteristics of zone anode current recovery can provide a basis for further improving electrolytic production operations and stabilizing reduction cells. |