Study on Coal-based Reduction Followed by Magnetic Separation of a Vanadium-titanium Magnetite Concentrate

Taking a vanadium-titanium magnetite concentrate with an iron grade of 61.08% and a TiO2 grade of 7.66% in Chengde, Hebei Province as the research object, a coal-based reduction followed by magnetic separation of vanadium-titanium magnetite concentrate was investigated. The effects of reduction temperature, reduction time, C/O molar ratio, and CaCO3 addition on reduction products and sorting indexes were investigated. Under the conditions of reduction temperature of 1350℃, reduction time of 120min, C/O molar ratio of 2.5, CaCO3 addition of 16%, and magnetic intensity of 85 mT, a magnetic products with TFe content of 87.19% and iron recovery rate of 82.62% and a non-magnetic products with TiO2 grade of 18.76% and TiO2 recovery rate of 79.40% were obtained. From the metallization rate of the reduction product and XRD analysis, it is found that the conversion of titanomagnetite to iron oxide, titanium oxide and metallic iron is difficult to occur. The conversion of titanomagnetite to CaTiO3, iron oxide and metallic iron can be promoted by increasing the amount of CaCO3 appropriately.