Simulation on the melting process of iron oxide pellet in slags

Abstract

On the basis of one-dimension non-steady heat transfer theory, a numerical model for the dynamic melting behavior of oxide pellet in molten slag was established and solved with finite difference method. The melting time at different conditions were calculated with the model and results showed good agreement with experiments. The melting times of pellet at 1450°C, 1500°C and1 550°C in molten slag bath are 56s, 36s and 25s; meanwhile, the maximum thicknesses of slag shell are 0.211cm, 0.149cm and 0.109cm respectively. The melting rate increases with the elevation of slag bath temperature and pellet preheating temperature. The melting times are almost the same for slag basicity of 0.8-1.2, but it will be much longer when the basicity is below 0.8. The maximum thickness of slag shell increases with the increases of pellet metallization ratio and pellet size, but the former has less effect on melting time than the latter.