METHOD OF NEPHELINE CONCENTRATE DESILICONIZATION AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2019 - IPC C22B4/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to processing of nepheline concentrate to obtain synthetic bauxite containing up to 80 % Al₂O₃ and up to 1.5 % SiO₂. Method involves preparation of charge from concentrate and carbon and carbothermal reduction melting of charge in electric furnace to produce oxide melt. Carbothermal reduction melting is carried out in one step in crucible of direct-polar DC plasma-arc furnace at temperature of 2200–3000 K in anode spot of arc with provision of desiliconization of nepheline concentrate as a result of reduction of silicon dioxide to monoxide and evaporation of the latter from oxide melt and obtaining a melt of synthetic bauxite containing up to 80 % of alumina, with a silicon module to 9, wherein said crucible diameter is equal to diameter of anode spot arc and is defined by expression , cm, where P is plasma arc power, kW.

EFFECT: invention can be used in aluminum industry for production of synthetic bauxite and dispersed silicon dioxide, which are used for production of alumina, metal aluminum, silicon, silicon carbide by known technologies.

2 cl, 2 tbl, 2 dwg