METHOD FOR PRODUCING ALUMINIUM BY ELECTROLYSIS OF ALUMINA SOLUTION IN CRYOLITE Russian patent published in 2024 - IPC C25C3/06 C25C3/18 

FIELD: non-ferrous metallurgy.

SUBSTANCE: method for producing aluminium consists of electrolysis of a solution of alumina in cryolite with 30% aluminium trifluoride during separate processes of melting, maintaining the specified temperature of the melt, and electrolysis itself (SEFCO technology). This makes it possible to radically reduce electricity consumption in the process of creating molten electrolyte and maintaining the specified temperature of the molten electrolyte by replacing electricity with the energy of combustion of organic fuel (for example, natural gas). First, in a gas or other furnace combined with an electrolysis bath, a cryolite melt with 30% aluminium trifluoride and 8% alumina is obtained at a temperature of 900-1000°C, then the current required to create the desired electrolysis mode is supplied from the electrolysis current source to the vertical bipolar low-consumption metal electrodes, and the cryolite ratio is maintained from 1.1 to 1.9. Alumina is added periodically as it is consumed. As the resulting primary aluminium accumulates, it is drained through a gate valve in the lower bottom part of the electrolysis bath.

EFFECT: reduced electric power consumption.

4 cl, 1 dwg