INFLUENCE OF WIDTH OF ANODE ON LOSSES OF METAL IN INDUSTRIAL ELECTROLYZERS USED IN THE PRODUCTION OF ALUMINUM

摘要

Mass transfer at the metal-electrolyte interphase boundary is investigated using a physical model of a vertical two-dimensional section of the electrolyzer at a 1:1 scale. The model, which is constructed from polymethyl methacrylate, is filled with liquids that are mutually practically insoluble: water ("metal") and PES-1 organosilicone liquid ("electrolyte"). The characteristics of mass exchange between the metal and electrolyte are found on the basis of the concentration of the water in PES-1 and on the basis of the material balances of the system. The density of the flow of the metal mass introduced into the electrolyte (J_(m/f)) depends (to within 15 percent) on the width of the anode (B). It turns out that J_(m/f)) approx = 0 for B approx = 0.6 m, which is nearly identical with the governing dimension of prebaked anodes. For electrolyzers with prebaked anodes the standing waves and emulsification of the metal in the electrolyte are practically absent, and as a result it is possible to attain the highest current efficiency of the metal, up to 94-96 percent.