磁选—浮选联合工艺从东鞍山铁矿浮选尾矿中回收铁的试验研究

Experimental Study on Iron Recovery from Flotation Tailings of Donganshan Iron Ore by Combined Magnetic Separation and Flotation Process

东鞍山烧结厂浮选尾矿TFe品位为22.82%,FeO含量为9.87%,SiO_(2)的含量为51.24%,S和P含量较低,均为0.03%,属于低硫、低磷、高硅型铁尾矿。此外,该尾矿-0.038 mm粒级含量高达56.44%,同时铁矿物主要集中在该粒级中,铁分布率达到67.62%。为了实现该铁尾矿的高效回收利用,本试验采用搅拌磨磨矿—弱磁选—强磁粗选—强磁精选—反浮选流程开展了系统的试验研究。结果表明:在搅拌磨磨矿细度为-0.038 mm占95%、弱磁选磁感应强度95 kA/m、强磁粗选磁场磁感应强度796 kA/m、强磁精选磁场磁感应强度398 kA/m的条件下,可获得TFe品位为38.20%、TFe回收率为63.51%的混合磁选精矿指标;将混合磁选精矿在矿浆温度40℃、矿浆pH值为11.5、淀粉用量1 000 g/t、CaO用量900 g/t、粗选捕收剂TD-2用量600g/t、一次精选捕收剂TD-2用量为300 g/t、二次精选捕收剂TD-2用量为300 g/t的条件下进行反浮选,闭路试验可获得TFe品位为62.34%、TFe作业回收率为55.10%的浮选精矿。全流程TFe回收率为35.00%,综合尾矿TFe品位为17.01%。试验结果可为东鞍山浮选尾矿中的铁矿物高效选矿回收提供指导。

The flotation tailings of the Donganshan sintering plant contain 22.82%Fe,9.87%FeO,51.24%SiO_(2) and a low S and P content of 0.03%,which belongs to low sulphur,low phosphorus and high silicon type iron tailings.In addition,the tailings contain 56.44%of the−0.038 mm particles.Also,the distribution of iron minerals in this size-level was 67.62%.In order to achieve efficient recovery of iron from this tailings,a systematic experimental study was carried out in this experiment using the process of stirred mill grinding-low intensity magnetic-high magnetic roughing-high magnetic selection-reverse flotation.The results showed that a mixed magnetic separation concentrate with a TFe grade of 38.20%and a TFe recovery of 63.51%was obtained at a fineness of−0.038 mm(95%),a magnetic induction of 95 kA/m for the low magnetic separation,high intensity magnetic field strength of 796 kA/m for roughing magnetic separation and high intensity magnetic field strength of 398 kA/m for cleaning magnetic separation.The appropriate reverse flotation conditions for mixed magnetic concentrates were pulp temperature 40℃,pulp pH 11.5,starch dosage of 1000 g/t,CaO dosage of 900 g/t,rougher collector TD-2 dosage of 600 g/t,primary cleaning collector dosage of 300 g/t and secondary cleaning collector dosage of 300 g/t.The flotation concentrate with iron grade of 62.34%and iron recovery of 55.10%was obtained by closed-circuit test.The continuous test for complete flow were carried out,the iron concentrate with iron grade of 62.43%and iron recovery of 35.00%was obtained,and the iron grade of comprehensive tailings was 17.01%.The test results can provide guidance for the high-efficiency beneficiation and recovery of iron minerals in the flotation tailings of Donganshan.