从细粒浸染状钼矿中有效回收微细粒辉钼矿

摘要

本文提出了一种从细粒浸染状钼矿中有效回收辉钼矿的浮选方案.为了最大限度地提高辉钼矿的回收率,系统地开展了原矿工艺矿物学、对比试验、工艺条件优化及颗粒尺寸分析等研究.工艺矿物学研究表明,原矿中61.63%的辉钼矿的粒度分布在小于20 μm粒级中,且它们与云母、黄铁矿共生呈包含状结构及微细粒浸染状结构.对比试验结果表明,常规浮选工艺对粒径小于25μm的颗粒回收效果不佳,而油团聚浮选工艺对微细粒辉钼矿的回收具有明显优势.油团聚浮选工艺利用变压器油作团聚油,团聚油用量变化对捕获的辉钼矿颗粒平均尺寸(d50 p)、团聚体平均尺寸(d50 a)及辉钼矿回收率影响显著.工业试验结果表明,与钼-硫混合浮选工艺相比,油团聚浮选工艺不仅使钼精矿的钼回收率提高22.75%,钼品位提升17.47%,而且还获得含硫38.92%的合格硫精矿.%An effective flotation approach is proposed for improving the recovery of molybdenite fines from a finely-disseminated molybdenum ore. To maximize the flotation recovery of molybdenum, process mineralogy of raw ore, contrast tests, optimization of operation conditions and particle size analysis were systematically investigated. Process mineralogy suggests that in the raw ore, 61.63% of molybdenite particles distribute in the <20 μm size fraction, and intergrow with muscovite and pyrite as the contained and disseminated type. Contrast tests indicate that conventional flotation responds to poor collection efficiency for particles less than 25 μm. Oil agglomerate flotation (OAF) process demonstrates an obvious superiority in improving the flotation recovery of molybdenite fines. Furthermore, the flotation results of OAF process reveal that the dosage of transformer oil plays a critical role on the average size of collected mineral particles (d50 p), agglomerates (d50 a) and the molybdenum recovery. In addition, industrial tests illustrate that compared with the Mo-S bulk flotation approach, OAF process not only increases Mo recovery and grade of molybdenum concentrate by 22.75% and 17.47% respectively, but also achieves a sulfur concentrate with a superior grade of 38.92%.