Oxidizing behaviors of carbon and silicon of molten iron by bottom-blown oxygen

摘要

Hot metal desilication is often carried out at low 1400°C in steel-making process. To clarify, the oxidizing behavior of silicon in molten iron is at a temperature greater than 1400°C. It was completed in an induction furnace by bottom-blown oxygen with CaO-SiO_2-CaF_2 flux at 1500°C. In addition, at 1350°C, desilication was also accomplished by bottom-blown oxygen with CaO-SiO_2-CaF_2 flux. The results are summarized as follows: (i) oxidation rate of carbon is higher than that of silicon, for Gibbs free energy of carbon of the hot metal is lower than that of silicon with the flux at 1500°C; (ii) the decreased rate of silicon gets lower than that of carbon with the flux at 1350°C during bottom-blown oxygen. This is an effective way to decarbonize and keep silicon from oxidation in hot metal.