某钒钛磁铁精矿深度还原-磁选试验研究

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

以河北承德某铁品位为61.08%,TiO_2品位为7.66%的钒钛磁铁精矿为研究对象,进行了钒钛磁铁精矿深度还原-磁选试验研究。考察了还原温度、还原时间、C/O摩尔比、CaCO_3添加量对还原产物和分选指标的影响。在还原温度为1350℃、还原时间100 min、C/O摩尔比2.5、CaCO_3添加量为8%、磁选场强为85 mT的条件下,可以得到全铁品位为87.19%、铁回收率为82.62%的磁性产品和TiO_2品位18.76%、TiO_2回收率为79.40%非磁性产品。由还原产物的金属化率与XRD分析得知,钛磁铁矿向铁氧化物、钛氧化物和金属铁的转化较难发生,适当增加CaCO_3的用量,能促进钛磁铁矿向CaTiO_3、铁氧化物和金属铁的转化。

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 100 min,C/O molar ratio of 2.5,CaCO3 addition of 8%,and magnetic intensity of 85mT,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.