PROCEDURE FOR PRODUCTION OF LOW CARBON FERROCHROMIUM Russian patent published in 2011 - IPC C22C33/04 

FIELD: metallurgy.

SUBSTANCE: procedure consists in melting ore-calcic melt and in pouring it into ladles, in supplying charge components in form of chromium containing ore materials and siliceous reducer into first ladle, in supplying charge components in form of siliceous reducer and solid additive consisting of chromite ore and lime into second ladle, an in mixing contents of two ladles. Metal chromium containing wastes of home fabrication at amount of 1-5 % of weight of ore-siliceous melt in the first ladle are supplied to ore-siliceous melt in the first ladle, while chromium containing ore materials and siliceous reducer are supplied at amount facilitating production of fusible slag with basicity 1.5-1.9 and contents Al₂O₃ 4-8 wt % and metal with content of silicon 1.5-8 wt %. Also, ratio of charge components of the second ladle is chosen so, as to facilitate basicity of produced slag 1.7-2.0 upon mixing with metal of the first ladle, while upon mixing contents of both ladles slag-metal melt is subjected to additional pouring from ladle to ladle 2-5 times.

EFFECT: production of stabilised slag; increased extraction of chromium into metal and raised efficiency.

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