梅山铁矿深部样精细分级-预选工艺优化

梅山铁矿石为磁铁矿-赤铁矿混合型铁矿石，铁品位为37.82%。现场采用不同的工艺分别对50～20、20～2、2～0.5 mm粒级进行预选，不仅预选尾矿铁品位较高，且50～20 mm粒级跳汰预选抛尾量非常低、耗水量大、生产指标不稳定、设备故障率也高。为了改善预选效果，进行了系统的选矿试验。结果表明，将现场50～20 mm粒级再破碎至20～0 mm并相应分级后，-0.5 mm粒级采用湿式筒式弱磁选+立环脉动高梯度强磁选，2～0.5 mm粒级采用筒式弱磁选+立环脉动高梯度粗粒强磁选，20～2 mm采用筒式中磁干选+辊式强磁干选，取得了铁品位为56.31%、铁回收率为3.65%的铁精矿，以及铁品位为40.81%、铁回收率为89.92%的预选精矿，预选尾矿铁品位16.75%、产率达11.59%，预选指标较好。

Precise Classification-Preconcentration Process Optimization Test of the Deep Ore from Meishan Iron Mine

The ore from Meishan iron mine is a compound of magnetite and hematite, and the iron grade is 37.82%. Preconcentration on-site was conducted for 50~20 mm, 20~2 mm and 2~0.5 mm size fraction, respectively, with different process. The results show that the iron grade of preconcentration tailing was high, and discarding tailings in 50~20 mm size fraction jig preconcentration is lower, high water consumption, unstable production index and high equipment failure rate. In order to improve the preconcentration efficiency, system test was carried out. The 50~20 mm size fraction ore was crushed to 20~0 mm then was relatively classified. -0.5 mm size fraction via drum-type low intensity wet magnetic separation and vertical ring-pulsating high gradient magnetic separation, 2~0.5 mm via drum-type low intensity magnetic separation and vertical ring-pulsating high gradient magnetic separation, 20~2 mm via drum-type medium intensity dry magnetic separation and roll-type high intensity dry magnetic separation, respectively. Iron concentrate with grade and recovery was 56.31% and 3.65%, preconcentration with grade and recovery was 40.81% and 89.92%, tailings with iron grade of 16.75% and yield rate 11.59%. The preconcentration results index is satisfaction.