Mass Action Concentration Calculation and Experimental Study on Molten Vortex Direct Reduction of Vanadium–Titanium Magnetite

In order to realize the comprehensive and efficient recovery of vanadium–titanium magnetite, a mass action concentration calculation model for direct melting reduction was established, and the mechanisms and limiting factors for the separation and enrichment between Fe, V, and Ti were also studied through molten vortex direct reduction experiments. The mass effect concentration modeling results show that increasing the temperature and carbon–iron ratio promotes Fe, Ti, and V reduction, while adding CaO and MgO inhibits Ti reduction. CaO and MgO in the slag preferentially combine with TiO2 rather than SiO2, and increasing MgO in the slag contributes to the decomposition of the Al2O3.TiO2. Vortex stirring efficiently prevents slag crusting, alleviates foam slag problems, and promotes full reaction in the melt. Appropriate increases in reaction temperature, carbon–iron ratio, and holding time are beneficial for reduction in the molten vortex direct reduction process, while excessive increases in these parameters will result in titanium reduction. Under optimal experimental conditions, the recovery of Fe and V in the metal is 99.61 to 99.74 pct and 92.63 to 94.3 pct, respectively, with TiO2 content in the slag being 50.9 to 51.2 pct, and TiO2 in the slag mainly concentrated in Mg0.6Ti2.4O5.