Research on New Technology of High-efficiency Comprehensive Utilization of Vanadium-titanium Magnetite

In order to achieve low-temperature reduction of vanadium-titanium magnetite,high-value utilization of iron powder,and clean utilization of vanadium-rich titanium materials,a new process which includes grinding and removal of impurities,ore,coal,sodium salt mixed to make agglomerates,direct reduction-grinding,secondary reduction of iron powder,sodium roasting to extract vanadium for efficient and comprehensive utilization of vanadium-titanium magnetite was proposed.The results show that the grinding treatment of vanadium-titanium magnetite concentrate can effectively remove impurities,laying the foundation for the subsequent production of high-quality iron powder and efficient vanadium extraction.The addition of sodium salt can greatly reduce the direct reduction temperature and improve the reduction effect.After grinding and selecting the primary reduced iron powder and secondary reduction,the reduced iron with 98.72% grade can be obtained,and its chemical compositions and process performances reach the industrial first-level iron powder standard.V₂O₅ with 98.12% of purity can be obtained from the vanadium titanium enriched material by sodium oxidation roasting-water leaching-acid ammonium salt vanadium precipitation-calcination and deamination.A titanium-rich material with a TiO₂ grade of 49.61% can be obtained from the leaching residue through dilute sulfuric acid leaching.Under the selected conditions,the total recovery rates of Fe,V₂O₅ and TiO₂ from vanadium-titanium magnetite concentrates to secondary reduced iron powder,V₂O₅ products and titanium-rich materials are 90.75%,82.71% and 89.63%,respectively.