Slag-metal Separation and Reduction Behaviors of Vanadium-bearing Titanomagnetite Metallized Pellets

Abstract

Vanadium oxides in metallized pellets can be reduced into metal phase by carbothermal reduction reaction in electric furnace smelting process. Smelting-separation parameters have an important influence on slag-metal separation and reduction behaviors of vanadium oxides. The effects of smelting temperature, slag basicity and smelting time on slag-metal separation, the mass fractions of V and C in metal phase and recovery degree of V for vanadium-bearing titanomagnetite metallized pellets were investigated in the present work. The results demonstrate that the increase of smelting temperature promotes the reduction of vanadium oxides, resulting in an increases of the mass fraction and recovery degree of V, whereas the mass fraction of C decreases continuously. Within proper slag basicity and smelting time ranges, increasing basicity and time is beneficial to the coalescence and settlement of metallic iron droplets and reduction of vanadium oxides in smelting separation process. The mass fraction and recovery degree of V increases firstly and then decreases with the increment of slag basicity and smelting time, whereas the mass fraction of C initially decreases and subsequently increases, showing an opposite tendency with that of V. Under the optimal conditions, smelting temperature of 1450°C, slag basicity of 0.7 and smelting time of 40 min, the recovery degree of V could reach the highest of 99.8%, and the mass fraction of V and C are 0.27% and 1.2%, respectively.