PROCESS FOR ACCURATELY CONTROLLING THE RATE OF INTRODUCTION AND THE CONTENT OF ALUMINA IN AN IGNEONS ELECTROLYSIS TANK IN THE PRODUCTION OF ALUMINUM

摘要

A process and apparatus for controlling the rate of introduction and the content of alumina into a tank for the production of aluminium by the electrolysis of dissolved alumina in a cryolitebase bath. The upper part of the bath forms a solid crust within a narrow range of the top between 1% and 3.5%. The alumina is introduced directly into the molten cryolite bath by way of at least one opening which is kept open in the solidified crust.