一种新型干式磁选机的抛尾试验研究

Experiment Research on Dry-type Tailings Removal of a New Magnetic Separator

为实现某铁矿选矿厂低品位磁铁矿的有效预选,提高选矿厂入磨铁矿石的品位,减少后续磨选作业的矿量,降低选矿厂能耗,研制了一种适用于细粒级矿石预选抛尾的新型干式磁选机。该设备采用多级滚筒串联组合、单机多次分选的设计,能够实现非磁性物与磁性物的有效分离。使用研制出的试验样机对该选矿厂TFe品位13.51%,MFe品位3.98%,粒级-4mm的原矿进行了一系列的干式抛尾选别试验。通过试验得到了一种适合多滚筒串联磁选机的最佳运行方式,当滚筒转速自上而下转速逐渐减小、磁辊磁场强度逐渐升高时,预选抛尾的指标最好。在三级滚筒转速依次为115 r/min、105 r/min、95 r/min,滚筒表面磁场强度依次为110 mT、120 mT、220 mT时,可获得MFe品位18.43%、回收率87.1%的预选精矿,抛除产率89.69%、MFe品位0.57%的尾矿,大大减小了后续磨矿的处理量,降低了选矿成本。该新型干式磁选机不受水资源条件的限制,在缺水地区的贫铁矿富集方面有很好的发展和应用前景。

In order to realize the high efficient pre-concentration of separating fine crushing magnetite ore,improve the grade of grinding,reduce the quantity of grinding operation and reducing the energy consumption in a dressing plant,a new type of multiple rolls dry permanent magnetic separator which can implement low iron was developed.Low grade magnetite mineral with particle size for 0~4 mm and iron grade of 13.51%and magnetic iron grade of 3.98%was choosed for testing by using the new magnetic separator.The results show that the indexes of pre-concentration are best when magnetic separator set as the top-down speed gradually decreases,and the magnetic field intensity of roller gradually increases.The results also show that the pre-concentration with MFe grade of 18.34%and recover rate of 87.1%can be obtained,the tailing with yield of 89.69%and MFe grade of 0.57%can be discharged.Pre-separation can reduce the amount of grinding and the cost of mineral processing.The new magnetic separator is not restricted by water resources and have a good development and application prospect in the enrichment of poor iron ore in water shortage areas.