Effect of Slag Content Control on Vanadium Loss in Ferrovanadium Smelting Process

Based on the smelting performance and slag control situation during the ferrovanadium industrial preparation process,the theoretical amount of slag produced by different vanadium oxides and different smelting stages was analyzed,and the slag amount and precise slag control technology of multi-stage electroaluminothermic ferrovanadium smelting process were proposed.The effects of knotting process,slag distribution and smelting period on slag compositions,slag weight and vanadium loss in slag were investigated.Experimental results indicated that the weight of Al₂O₃ by thermite reaction was calculated to be 0.78 kg and 0.91 kg when the purity（TV,total vanadium）of V₂O₃ and V₂O₅ was 63.5% and 55.2%,respectively.Increasing the knotting strength and density,reducing the proportion of casting slag and prolonging the smelting period were beneficial to reduce the actual slag weight and the vanadium loss in the slag.The average MgO content in ferrovanadium slag reduced from 16.4% to 8.0% and the content of Al₂O₃increased from 61.1% to 69.3% through the optimization of smelting and ramming process.The ratio and the vanadium content of casting slag respectively decreased by 20.2% and 38.4% on the basis of the total slag amount reduced by 11.8%,and the corresponding vanadium loss was reduced from 79.0 to 61.1 kg per furnace,which means that the recovery rate of FeV50 alloy increased by 0.39% under the optimal conditions.