姑山极微细粒赤铁矿石选矿工艺流程改进探索试验

姑山赤铁矿石硬度大、嵌布粒度极微细，目前的选矿工艺指标低（块精矿铁品位48%、粉精矿铁品位57%）。为探索提高姑山极微细粒赤铁矿石选矿工艺指标的途径，在实验室进行了阶段磨矿-阶段强磁选-阴离子反浮选探索试验。结果表明：在一段磨矿细度为-0.074 mm占85%条件下，经一阶段强磁选（1粗1扫，粗选、扫选磁场强度分别为477 kA/m、637 kA/m），强磁选精矿再磨至-0.030 mm占87%，经二阶段强磁选（1粗1扫，粗选、扫选磁场强度分别为477 kA/m、716 kA/m）-1粗1精阴离子反浮选（以NaOH为pH调整剂、淀粉为抑制剂、石灰为活化剂、RA-915为捕收剂），获得的浮选精矿铁品位可达63.96%，说明采用阶段磨矿-阶段强磁选-阴离子反浮选工艺将姑山铁矿铁精矿品位提高至63%以上在技术上是可行的。试验结果可以为姑山极微细粒赤铁矿石合理选矿工艺流程的确定提供参考。

Preliminary Study on Optimization of Gushan Micro-fine Hematite Mineral Processing Flowsheet

Gushan hematite has high hardness and micro-fine dissemination size， and low ore dressing technology index（48% of iron lump concentrate grade and 57% of iron powder concentrate grade）.In order to explore the way to improve the process index of Gushan ultrafine hematite ore dressing， the stage grinding-High Intensity Magnetic Separation（HIMS）-anion reverse flotation test was carried out in the laboratory. The results show that: at first stage grinding fineness of 85% passing 0.074 mm， via first stage magnetic separation （one roughing one scavenging， magnetic field intensity of roughing and scavenging is 477 kA/m and 637 kA/m， respectively）， the magnetic concentrate reground to 87% passing 0.030 mm， via second stage magnetic separation （one roughing one scavenging， magnetic field intensity of roughing and scavenging is 477 kA/m and 716 kA/m， respectively）， one roughing one scavenging anionic reverse flotation（（NaOH as pH adjusting agent， starch as inhibitor， lime as activator， RA-915 as collector）， the iron grade of flotation concentrate is 63.96%， which shows that it is feasible to use the stage grinding-stage HIMS-anion reverse flotation process to increase the iron concentrate to larger than 63%. The experimental results can provide references for the determination of reasonable beneficiation process of ultrafine hematite in Gushan.