Research and practice on hydrogen metallurgy-electric furnace melting separation process for vanadium-titanium magnetite

To address the prominent problems of low titanium recovery, high energy consumption, and high carbon emissions in the traditional blast furnace basic oxygen furnace process for smelting vanadium-titanium magnetite, this paper proposed a process route of hydrogen metallurgy coupled with electric furnace melting separation for vanadium titanomagnetite, and conducted fundamental research and industrial trials. First, oxidized pellets were prepared using vanadium-titanium magnetite as raw material. Then these pellets were then used to produce metallized pellets via hydrogen based shaft furnace. Finally, electric furnace melting separation was applied to achieve the separation and enrichment of iron, vanadium, and titanium. Based on this approach, this study systematically investigated the optimal control conditions for each process step including oxidized pellet production, hydrogen based reduction, and electric furnace melting separation. Experimental results show that oxidized pellets meeting the requirements for hydrogen based shaft furnace can be obtained under preheating temperature of 930 ℃ and preheating time of 18 min. Increasing the reduction temperature and the H₂ volume fraction significantly improves the reducibility index, while high temperature and low H₂ volume concentration exacerbate pellet reduction swelling and sticking behavior. The low temperature reduction disintegration index first increases and then decreases with rising H₂ volume fraction. The optimal slag metal separation for electric furnace melting separation is achieved at 1 600 ℃ with a C/O mole ratio n（C）/n（O） of 1∶1. Industrial trial results demonstrate that the average recovery rates of iron and vanadium in vanadium bearing hot metal exceed 95% and 90% respectively, and the average recovery rate of titanium in titanium slag reaches over 92%. This process achieves efficient recovery of the three valuable components of iron, vanadium, and titanium from vanadium-titanium magnetite, providing a new technical solution and theoretical support for the high value and green utilization of vanadium-titanium magnetite.