Crust hole repair for electrolytic cells
AssigneeAlcoa Inc.
InventorH. Wayne Cotten
Life of this patent
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Abstract
A process for repairing a hole in the crust of an electrolytic cell. The hole is repaired by covering it with a receptacle containing solid particles. The receptacle comprises a polymeric material. More preferably, the receptacle comprises a cellulosic material, such as paper, polymer-impregnated paper, or cardboard. A closed paper bag having at least two paper layers and weighing about 15-20 lb. (6.8-9.1 kg) is particularly preferred. When the electrolytic cell produces aluminum by electrolysis of alumina, the solid particles comprise an aluminum compound such as alumina, aluminum fluoride, cryolite, or a mixture of such compounds. Two preferred forms of alumina include smelting grade alumina (SGA) and alumina dust collected by an electrostatic precipitator (ESP dust).
Claims24
In an electrolytic cell wherein a metal is produced by electrolysis, said cell comprising a molten electrolyte at an elevated temperature and above said electrolyte a crust defining a hole through which heat is lost from said electrolyte, the improvement in the operation of said cell comprising repairing said hole by covering it with a receptacle containing solid particles comprising alumina.
An electrolytic cell for producing a metal by electrolysis, said cell comprising a chamber containing a molten electrolyte at an elevated temperature, above said electrolyte a crust defining a hole, and a covering for said hole comprising a receptacle containing solid particles, said crust supporting said receptacle upward of and spaced from said electrolyte, thereby reducing heat loss from said electrolyte through said hole.
Dependencies are inferred from the claim text.