Managing the Electrolysis Process by Integrating In Situ Measurements of the Bath’s Properties

Abstract

Control of the bath’s composition and temperature is crucial to the stability, energy consumption and material efficiency of the aluminium electrolysis process. The traditional approach involves periodic measurement of the bath’s composition with x-ray diffraction, as well as the bath’s temperature. The sampling and corrective measures applied to the cell can take 8–12 h. Since the relationship between the excess AlF₃ in the bath and the temperature is difficult to manage, the electrolysis process involves a time lapse. With the integration of in situ measurements of the bath’s properties in the electrolysis cell, optimization of the primary aluminium reduction process was achieved. Increased measurement frequencies and the integration of in situ measurements into the electrolysis process reduced the instability of the process, resulting in energy savings and increased current efficiency of 96.4%.