东鞍山贫赤铁矿石阶段磨矿—磁选—阴离子反浮选试验

Research on the Stage Grinding-Magnetic Separation-Reverse Anion Flotation Technological of Lean Hematite Ore from Donganshan

东鞍山铁矿石铁品位为33.28%;铁主要以赤褐铁矿形式存在,分布率为86.47%,但3.29%的铁以菱铁矿形式存在,会对浮选产生不利影响。现场采用两段连续磨矿—粗细分级—粗粒螺旋溜槽重选、重选中矿再磨后与细粒磁选精矿合并反浮选工艺,存在尾矿品位偏高,重选处理量小,精矿铁回收率低等问题。为此,对东鞍山铁矿厂现场原矿进行了两段阶段磨矿—阶段磁选—磁选精矿再磨后1粗1精3扫、中矿顺序返回闭路反浮选试验,可获得铁品位为65.32%、回收率为75.71%的精矿,尾矿铁品位为13.38%。与现场原工艺流程相比,铁品位提高了0.58个百分点、回收率提高了10.43个百分点,且该工艺流程简单,易于实现工业改造。该试验结果对改善东鞍山贫赤铁矿选别指标有重要的指导意义,并可为国内其他贫赤铁矿的开发利用提供参考。

There is 33. 28% iron in a low-grade hematite ore from Donganshan. Iron mainly exists in form of hematite and magnetite,with distributive ratio of 86. 47%. 3. 29% of the iron exists in form of siderite,which would have bad effect on flotation operation. Twice stages grinding-classification-gravity separation by spiral chute on coarse particles,middlings of gravi-ty separation reground and then mixed with fine magnetic concentrate,the mixture endure flotation operation is selected for on-site process. The existing process has problems of high grade tailings,small capacity in gravity separation,low yield rate and i-ron recovery. Twice stage grinding stage magnetic separation, one roughing-one cleaning-three scavenging reverse flotation process on reground magnetic concentrate is conducted on run-of-mine ore from Donganshan. Iron concentrate with iron grade of 65. 32% and recovery of 75. 71%,tailings of 13. 38% Fe were obtained. Compared with the original technological process,the iron grade increased by 0. 58 percentage points and the recovery rate increased by 10. 43 percentage points,and the process is simple and easy to be realized. The experiment results has important guiding significance for beneficiation index improving of the hematite ore in the Donganshan,and can provide reference for the development and utilization of the ore in same type.