METHOD OF FEEDING ELECTROLYTIC CELL WITH ALUMINA AND DEVICE FOR ITS IMPLEMENTATION

摘要

FIELD: technological processes.;SUBSTANCE: invention relates to a method and a device for alumina feed of an electrolysis cell for aluminum production. Proposed method comprises feeding alumina from bunker into electrolyte melt and feeding control by means of device with controlled parameters. Alumina in electrolytic cell is continuously fed to melt surface in amount which provides concentration of dissolved alumina in melt in range of 1.5÷3.0 wt%, value of supply is regulated as to current strength of electrolysis cell, at the same time gap is kept open in crust of electrolyte by means of sealing of gap between lower end of conical flare of alumina supply device and surface of electrolyte with cryolite-alumina backfill with thickness of 1–4 cm. Dipping of alumina into melt is performed due to pressure of compressed air supplied to device in volume equal to volume of alumina loaded into unit of time into electrolysis unit. Disclosed is an apparatus for powering an aluminum electrolysis cell with alumina, comprising a hopper, a dispenser and feed means, note here that hopper is made up of two boxes arranged one above the other – top and bottom scales interconnected by rotary feeder to feed alumina from top to bottom basket. Lower part of alumina feed branch pipe has conical funnel with opening angle 45–50°, located at distance of 3–5 cm from the melt surface. Flow distributor is arranged inside conical flared end.;EFFECT: continuous supply of the electrolytic cell with alumina, exclusion of the puncheon from the APF system, which submerges the loaded portion of alumina into the electrolyte, reduced fluoride carryover into the gas removal system and reduced risk of precipitation on the bottom of the electrolysis cell.;5 cl, 3 dwg, 1 tbl