PROCESS OF START-UP OF ALUMINUM ELECTROLYZER AFTER OVERHAUL Russian patent published in 1999 - IPC

FIELD: electrolysis of aluminum. SUBSTANCE: process of start-up of aluminum electrolyzer after overhaul includes charging of starting burden containing fresh cryolite, calcium fluoride, sodium-aluminum fluorides and sodium- carrying component, pouring of electrolyte, electric connection of electrolyzer and pouring of metal. Soda ash is used in the capacity of sodium-carrying component, its content in mixture of starting burden is kept at level of 20-50 per cent by mass. Mixed (floatation and regeneration ) cryolite and/or circulating electrolyte in the amount less than 50% of mass of fresh cryolite is used as sodium-aluminum fluorides. EFFECT: decreased operational cost of start-up of electrolyzer after overhaul, increased resistance of lining and prolonged service life of it, diminished loses of fluoride salts ( diminished harmful discharges ), reduced consumption of electric energy for start-up of electrolyzer, shortened time of bringing electrolyzer to production of high-quality aluminum. 1 cl