高温透明铝电解槽中 50cm2石墨阳极上气泡析出行为的研究 [Bubble behavior on 50 cm2 graphite anode in transparent Hall-Heroult electrolytic cell ]

Abstract

In aluminum electrolysis, understanding the anodic bubble behavior has been critical for bath flow field simulation and anode effect investigation. In this paper, bubble behavior on graphite anodes with underside surface area of 50 cm2 (10 cm×5 cm) was studied in a transparent Hall-Heroult electrolytic cell at 924 ℃. The results indicate that the largest bubble coverage on the graphite anodes operated at 0.3−1.7 A/cm2 is in the range of 48%−65%, which agrees with the data obtained on industrial aluminum reduction cell, and lower than that of the smaller anodes, 60%−100%, reported in literatures. Priority sites for bubble nucleation were found to be linked to a highly layered carbon structure on the anode surface combined with SEM/EDS analysis. The layered carbon structure illustrates good wettability to CO2 bubbles, preventing adhered bubbles from gliding across the anode to result in the formation of large bubble.