BLEND AND METHOD OF ALUMINOTHERMAL PRODUCTION OF CHROMIUM METAL USING SAID BLEND Russian patent published in 2013 - IPC C22B34/32 C22B5/04 

FIELD: metallurgy.

SUBSTANCE: proposed blend contains 56.5-57.3 wt % of chromium oxide, 24.2-25.4 wt % of aluminium, 8.4-8.6 wt % of sodium or potassium dichromate, 2.8-4.3 wt % of chromium anhydride, 2.55-2.65 wt % of calcium hydroxide with carbon content of not over 0.2 wt %, 0.40-0.45 wt % of table salt, 0.9-1.1 wt % of fluorspar concentrate, 1.4-1.7 wt % of lime with carbon content not over 0.2 wt % and 1.15-1.45 wt % with carbon content not exceeding 0.5 wt %. First, calcium and sodium hydroxides or calcium dichromate are mixed in drum mixer. Then, chromium oxide, aluminium, table salt, lime with carbon content not exceeding 0.2 wt % and chromium anhydride are loaded in said drum mixer and mixed. Produced mix is loaded into hearth. Blend is smelt at the rate of 360-460 kg/m²·min, some 2-4 min before smelting end lime with carbon content not exceeding 0.5 wt % is loaded onto furnace top. Portion of slag is discharged from said hearth into mould on wall accretion to load fluorspar concentrate onto remained slag. After complete dissolution of the latter it is discharged and chromium metal.

EFFECT: higher yield of chromium metal.

2 cl, 1 tbl, 2 ex