辽西风化壳型钒钛磁铁矿预富集试验研究

针对辽西风化壳型钒钛磁铁矿有用矿物难以回收利用的问题，进行了详细的工艺矿物学研究。矿石中金属矿物主要为磁铁矿、（钛）磁铁矿、钒磁铁矿、钛铁矿，非金属矿主要有长石、角闪石和石英。其中钛、钒主要以类质同象的形式赋存在磁铁矿中，且矿石中磁铁矿、钛铁矿及脉石矿物嵌布关系复杂，解离困难。分别采用直接磨矿-弱磁选预富集、粗粒干式预抛尾-磨矿-弱磁选预富集、粗粒湿式预抛尾-磨矿-弱磁选预富集工艺进行了预富集工艺对比试验。结果表明，粗粒湿式预抛尾-磨矿-弱磁选无论在功耗还是回收率指标方面均优于其余2种工艺。采用该工艺在磨矿细度为-0.074 mm占70%条件下，获得了V₂O₅含量为1.561%、回收率为60.96%，TFe品位为40.43%、回收率为24.83%的预富集精矿，可以满足后续直接酸浸提钒的工艺要求。对粗粒湿式预抛尾-磨矿-弱磁选工艺获得的精矿、尾矿进行分析检测表明，钒、钛以类质同象的形式替换磁铁矿中的铁，使预富集精矿铁品位较低，预富集精矿中磁铁矿、钛磁铁矿、脉石矿物嵌布关系复杂紧密，无法通过机械磨矿使其解离。因此，即使继续增加磨矿细度，预富集精矿全铁品位也仅能保持在40%左右，不能再继续提高。

Experiment Study on Preconcentration of Weathering Crust Vanadium Titanium Magnetite in Western Liaoning Province

A detailed study on process mineralogy of weathering crust-type vanadium-titanium magnetite in western Liaoning Province was carried out in view of the difficulty in recycling it’s useful minerals. The metal minerals in the ore are mainly magnetite， titanomagnetite， vanadium magnetite， and ilmenite. Non-metallic minerals mainly include feldspar， amphibole and quartz. Among them， titanium and vanadium mainly occur in the form of isomorphism in magnetite， and the distribution relationship of magnetite， ilmenite and gangue minerals is complex， which is difficult to be liberated. The comparative experiments of preconcentration processes were carried out by direct grinding - low intensity magnetic separation preconcentration， coarse particles dry pre-discarding-grinding-low intensity magnetic separation preconcentration， and coarse particles wet pre-discarding-grinding-low intensity magnetic separation preconcentration. The results show that wet pre- discarding-grinding-low intensity magnetic separation is superior to the other two processes in terms of power consumption and recovery index. Under the condition of grinding fineness of -0.074 mm is 70%， the preconcentrated concentrate with V₂O₅ content of 1.561%， recovery of 60.96%， TFe grade of 40.43% and recovery of 24.83% was obtained， which can meet the requirements of subsequent direct acid leaching and vanadium extraction. The analysis of the concentrate and tailings obtained by the wet pre-discarding- grinding-low intensity magnetic separation process shows that vanadium and titanium replace the iron in the magnetite in the same way as the crystal， so that the preconcentrated concentrate iron grade is low， and the magnetite， titanomagnetite and gangue mineral in the preconcentrated concentrate are complicated and inseparable， and cannot be dissociated by mechanical grinding. Therefore， even if the grinding fineness continues to increase， the total iron grade in the pre-enriched concentrate can only be maintained at about 40% and cannot be continuously improved.