辽宁某低品位铁矿石磁重联合回收铁试验研究

Experimental Study on Comprehensive Recovery of a Low-grade Iron Ore by Magnetic Gravity Combination in Liaoning Province

辽宁某低品位铁矿石TFe含量28.38%,矿石矿物组成简单,高硅、贫铁,且含有少量铝,为原生矿石。采用“原矿粗粒级预先抛尾—预选精矿再磨再选—磁选精矿再重选提品位”的磁重联合工艺进行分选,考察了磁感应强度、磨矿细度、离心机转速等对分选指标的影响。结果表明:在弱磁抛尾磁感应强度为0.1 T,强磁抛尾磁感应强度为1.3 T,预选精矿磨矿细度为-0.074 mm占85%,弱磁精选磁感应强度为0.1 T,强磁精选磁感应强度为0.8 T,离心机转速为450 r/min条件下,通过连续扩大半工业试验可获得综合精矿产率31.39%、铁品位63.30%、铁回收率70.03%的指标,为我国贫铁矿回收利用提供了参考及试验依据。

A low-grade iron ore in Liaoning with TFe content of 28.38%.The ore mineral composition is simple,high silicon,poor iron,and contains a small amount of aluminum,which is a primary ore.The magnetic-gravity combined process of pre-discarding tailings of coarse-grained ore-regrinding and re-concentration of pre-concentrate-regravity of magnetic concentrate was used for separation.The effects of magnetic induction intensity,grinding fineness and centrifuge speed on separation index were investigated.The results show that under the conditions that the magnetic induction intensity of low intensity magnetic tailings discarding is 0.1 T,the magnetic induction intensity of high intensity magnetic tailings discarding is 1.3 T,the grinding fineness of pre-concentrate is-0.074 mm accounting for 85%,the magnetic induction intensity of low intensity magnetic cleaning is 0.1 T,the magnetic induction intensity of high intensity magnetic cleaning is 0.8 T,and the centrifuge speed is 450 r/min,the comprehensive concentrate yield is 31.39%,the iron grade is 63.30%,and the iron recovery rate is 70.03%.It provides a reference and experimental basis for the recovery and utilization of lean iron ore in China.