莱新铁矿石选铁试验研究

Experimental Study on Iron Separation from Laixin Iron Ore

莱新铁矿石中赤(褐)铁矿、假象赤铁矿、磁铁矿为主要铁矿物,三者合计铁分布率占96.93%;常见脉石矿物为方解石、云母(包括白云母、黑云母和金云母)和绿泥石,主要脉石成分SiO_(2)含量为7.70%,有害杂质硫含量为0.74%。为优化现场选矿工艺流程,改善分选指标,开展了选矿试验研究。结果表明:①试样在磨矿细度为-0.075 mm55%的情况下进行弱磁选(119.43 kA/m),可获得TFe品位67.85%,回收率71.16%的弱磁选精矿。②弱磁选尾矿在背景磁感应强度为1.52 T、中矿冲洗水压为0.15 MPa的情况下进行强磁选,强磁选精矿在磨矿细度为-0.075 mm占75%、NaOH用量为1000 g/t、淀粉用量为800 g/t、CaO用量为300 g/t、CY-282用量为1200 g/t、浮选温度为35℃的条件下进行反浮选,可获得TFe品位65.62%,回收率19.85%的反浮选精矿。③磨矿—弱磁选—强磁选—再磨—反浮选工艺流程是该矿石处理的高效流程。

Hematite(limonite),illusive hematite and magnetite are the main iron minerals in Laixin iron ore,the total iron distribution rate is 96.93%.The common gangue minerals are calcite,mica(including muscovite,biotite and phlogopite)and chlorite,the main gangue composition SiO_(2) content is 7.70%,the harmful impurity sulfur content is 0.74%.In order to optimize the field beneficiation process and improve the separation index,the beneficiation experiment was carried out.The results showed that:①Low intensity magnetic separation(119.43 kA/m)was carried out under the conditions of grinding fineness of-0.075 mm 55%,and the concentrate with TFe grade of 67.85%and recovery of 71.16%was obtained.②High intensity magnetic separation of low intensity magnetic separation tailings was carried out under the conditions of 1.52 T background magnetic induction and 0.15 MPa flushing water pressure of medium ore,the reverse flotation of high intensity magnetic separation concentrate was carried out under the conditions of grinding fineness-0.075 mm 75%,NaOH dosage 1000 g/t,starch dosage 800 g/t,CaO dosage 300 g/t,CY-282 dosage 1200 g/t,flotation temperature 35℃,the reverse flotation concentrate with TFe grade of 65.62% and recovery of 19.85%can be obtained.③Grinding,low intensity magnetic separation,high intensity magnetic separation,re-grinding,reverse flotation process is the efficient process of the ore treatment.