Dissolution behaviour of manganese ore in basic oxygen furnace type slag

In order to improve manganese yield during the reduction process of manganese ore in blowing practices employing less slag at BOF, the dissolution behaviour of manganese ore in slag has been studied in an experimental scale. The effect of temperature, slag composition, addition of CaF₂, and pre-treatment of manganese ore was examined for the dissolution behaviour of manganese ore into BOF type slags. The precipitation of (Fe,Mn)O phase in slag was observed during the addition of manganese ore. The dissolution rate of manganese ore into molten slag increased with temperature, and also increased with the initial contents of FeO, MgO and MnO. However, the effect of slag basicity was not evident on the dissolution rate of manganese ore into slag. The addition of CaF₂ and pre-treatment of Mn ore were very effective to promote the dissolution of manganese ore into slag.