Effect of Molten Slag on the Dissolving Rate of Reduced Iron Pellets into Iron Melt

Abstract

The effect of molten slag on iron melt upon the dissolving rate of cylindrical reduced iron pellets made from Höganäs iron powders, Fe₂O₃ powders and pulverized additives was investigated. The following results were obtained:
(1) A small portion of iron oxide in pellets dissolved into the molten slag. The dissolving rate of pellets into iron melt was determined by neglecting the reduction of iron oxide in molten slag.
(2) The maximum dissolving rate appeared at about unit basicity of molten slag. The effect of molten slag on the dissolving rate could be explained from their viscosity and density. The molten slag of the lower viscosity and the lower density would be desirable for higher dissolving rates.
(3) The effect of molten slag with basicity of 0.5 and 1 on the temperature dependence of the dissolving rate into iron melt was small for pellets containing Fe₂O₃ and large for those without Fe₂O₃.
(4) The molten slag with unit basicity had little effect on the dissolving rate of pellets containing CaO, CaCO₃, C and flux (simultaneous addition of CaO and SiO₂). The iron oxide which dissolved into the molten slag increased with increasing prefused slag, SiO₂, and Al₂O₃ contents in pellets.