METHOD FOR CONTROLLING AN ALUMINA FEED TO ELECTROLYTIC CELLS FOR PRODUCING ALUMINIUM

摘要

The invention relates to nonferrous metallurgy and may be suitable forcontrolling the feed of alumina toelectrolytic cells for producing aluminum to maintain the aluminaconcentration in the electrolytic meltequal or close to the saturation value. To maintain the alumina concentrationwithin the set range, reducedvoltage U or pseudo-resistance R is measured. The measured values are recordedat fixed time intervals,underfeeding or overfeeding phases compared to a theoretical alumina feedingrate during electrolysis areformed, whereas the duration of underfeeding phases is selected depending onthe alumina concentrationin the electrolytic melt, and the duration of overfeeding phases is determinedaccording to the change ofone or more electrolytic cell parameters being recorded: reduced voltage, U,pseudo-resistance. R, rates ofreduced voltage, dU / dt, pseudo-resistance, dR / dt, change. Adjustments tothe anode-cathode distance tomaintain the electrolytic cell energy balance may be performed during any ofthe feeding phases. Theinvention improves the engineering and economic performance of the aluminumproduction process dueto elimination of anode effects in electrolytic cells with carbon anodes, aswell as by means of using novelstructural and electrode materials having a high rate of corrosion in the lowalumina concentrationelectrolytic melt.