Melting Behavior of Titanium-Bearing Electric Furnace Slag for Effective Smelting of Vanadium Titanomagnetite

Abstract

The melting behavior of titanium-bearing electric furnace slag is a key factor for effective smelting of vanadium titanomagnetite in electric furnaces. The melting behavior of synthetically produced CaO-SiO2-MgO-Al2O3-TiO2 slags with different TiO2 contents (48 wt.% to 54 wt.%), CaO/SiO2 mass ratios (0.8 to 1.4), and MgO contents (8 wt.% to 14 wt.%) was experimentally investigated in this study. The results demonstrate that the softening and melting temperatures decreased as the CaO/SiO2 ratio was increased but increased with increasing contents of TiO2 and MgO. The predicted slag phase composition showed that increasing the CaO/SiO2 mass ratio promoted CaTiO3 formation, whereas the proportion of MgTi2O5 phase increased with increasing MgO content. Appropriate slag compositions with binary basicity of 0.8 to 1.0, 10 wt.% to 12 wt.% MgO, and more than 48 wt.% TiO2 are suggested to obtain titanium-bearing electric furnace slag with low melting temperature and appropriate phase composition for titanium extraction.