Composite cell bottom for aluminum electrowinning
AssigneeMoltech Invent S.A.
InventorsVittorio de Nora, Jean-Jacques Duruz, Brian Cronin
Life of this patent
Estimating the term…
Abstract
A cell for the electrowinning of aluminum from molten salts has a cell bottom lining consisting partly of a refractory mass (4 ) and partly of carbon bodies (5). At least 30% and preferably 50% or more of the cell bottom area is occupied by the refractory mass (4). The carbon bodies (5) are level with the refractory mass (4) or are recessed therein.
Claims31
A cell for the electrowinning of aluminum from molten salts having a plurality of anodes disposed over a cell bottom comprising a carbon cathode through which current is supplied to a pool of molten aluminum on the cell bottom, characterized in that the cell bottom is lined with carbon sections, positioned longitudinally in the cell, and at least one mass of non-conductive, refractory material juxtaposed with the carbon sections to make up a composite cell bottom composed of adjacent areas of current-conducting carbon and non-conducting refractory material with vertical pins, plates or bars of metal resisting the operating temperature of the cell being inserted in the carbon sections and connected to collector bars, and with flat upper surfaces of the carbon sections being located lower than flat upper surfaces of said juxtaposed, non-conductive refractory material or of another refractory material present on said juxtaposed, non-conductive refractory material, and the total upwardly facing surface area of the carbon in the cell bottom located under the anodes being smaller than the horizontal surface area of the anodes.
A method of renovating a used cell bottom of an aluminum production cell which cell bottom is made up of rows of blocks of carbon connected to current supplying means, which method comprises replacing some of the used blocks of carbon with new blocks of carbon, and replacing the other used blocks of carbon with at least one mass of non-conductive, refractory material extending throughout the thickness of the cell bottom and juxtaposed with the carbon blocks to make up a composite cell bottom composed of adjacent areas of current-conducting carbon and non-conducting refractory material, positioning the upper surfaces of the carbon blocks lower than the upper surfaces of said juxtaposed, non-conductive refractory material, supplying sufficient to said carbon blocks to provide a total upwardly facing surface area of the carbon blocks in the cell bottom that is smaller than the horizontal surface area of the overlying anodes, and passing current from said carbon blocks of smaller surface area.
A cell for the electrowinning of aluminum from molten salts having a plurality of anodes disposed over a cell bottom comprising a carbon cathode through which current is supplied to a pool of molten aluminum on the cell bottom, characterized in that the cell bottom is lined with at least one body of carbon and at least one mass of non-conductive, refractory material extending throughout the thickness of the cell bottom and juxtaposed with the carbon body to make up a composite cell bottom composed of adjacent areas of current-conducting carbon and non-conducting refractory material with flat upper surfaces of the carbon body areas located lower than flat upper surfaces of said juxtaposed, non-conductive refractory material or of another refractory material present on said juxtaposed, non-conductive refractory material, and the total upwardly facing surface area of the carbon in the cell bottom located under the anodes being smaller than the horizontal surface area of the anodes.
Dependencies are inferred from the claim text.