Preparation of Oxidized Pellets of Vanadium Titanium Magnetite and Direct Reduction Behavior in Hydrogen-Based Shaft Furnace

Abstract

Herein, the optimized process parameters for the preparation of vanadium-titanium magnetite (VTM) pellets are determined, and an efficient and green utilization technology for VTM based on the integration of oxidation roasting-hydrogen-based shaft furnace direct reduction is established. The results indicate that the preferable VTM oxidized and pre-reduced pellets can be prepared by preheating at 925 °C for 18 min and roasting at 1200 °C for 25 min, followed by the reduction temperature of 1050 °C at the reduction atmosphere of 4% CO₂ and H₂/CO = 8. The corresponding compressive strength of the preheated and roasted pellets is 516 N per pellet and 2028 N per pellet, respectively. In addition, the LTD_+6.3 and LTD_UP of roasted pellets are 80.86% and 93.90%, and the corresponding reducibility index, reduction swelling index, and the reduction sticking index are 0.0428, 2.32%, and 2.50%, respectively. All of which meet the production requirements of hydrogen-based shaft furnace.