齐大山铁矿选矿工艺优化研究

Optimization of Beneficiation Technology on Iron Mine from Qidashan

齐大山铁矿矿石铁品位为31.56%,其中Fe O含量为6.59%,主要铁矿物为赤铁矿和磁铁矿,原采用阶段磨矿—粗细分级—重选—磁选—阴离子反浮选工艺,对微细粒铁矿物回收效果差。为改善细粒铁矿物的回收效果,提高选厂经济效益,对齐大山铁矿石开展了选矿工艺优化研究。结果表明:当一段磨矿细度为-0.074 mm占65%,二段磨矿细度为-0.074 mm占90%时,采用阶段磨矿—粗细分级—阶段重选—磁选—阴离子反浮选流程处理矿石,可以获得铁品位和回收率分别为66.80%和82.90%的综合精矿,其中重选精矿占比高达70.21%,弱磁选精矿占比为7.57%。一段螺旋溜槽粗选尾矿直接给入磁选—反浮选,能有效避免微细粒级铁矿物的损失;降低旋流器分级作业沉砂粒度,增加重选作业处理量;增加弱磁精选作业,直接产出最终精矿等措施,对降低浮选作业药剂用量和最终选矿成本具有重要意义。试验成果对实现鞍山式铁矿石的高效分选具有指导意义。

Iron grade of Qidashan iron ore is 31. 56 %,the content of FeO is around 6. 59 %,the main iron minerals are hematite and magnetite,the recovery of fine iron particles is not satisfactory via the original stage grinding-classification-gravity concentration-magnetic separation-anionic reverse flotation technology. In order to reduce production costs and improve economic benefits of Qidashan iron ore,new beneficiation process research was conducted. The results showed that with the first stage grinding fineness of 65 % passing 0. 074 mm,and second grinding fineness of 90 % passing 0. 074 mm,the concentrate with66. 80 % iron and recovery of 82. 90 % was obtained via the process of stage grinding-classification-stage gravity concentrationmagnetic separation-anionic reverse flotation process,comprehensive concentrate with iron grade of 66. 80 % and recovery of82. 90 % was obtained,gravity concentrate and low intensity magnetic concentrate account for 70. 21 % and 7. 57 % of total concentrate. Tailings of first stage spiral chute via magnetic separation-reverse flotation,can effectively avoid fine iron ore loss.Decrease of grit size for classification increase the capacity of gravity separation,adding low intensity magnetic clean separation process to produce final concentrate,has important significance of decrease reagent dosage even the total beneficiation cost. The results has guidance meaningful for realization of high efficient separation of Anshan-type iron ore.