鞍山式铁矿重选精矿工艺矿物学研究

随着辽宁某选厂重选精矿的铁品位变低，其已不能作为精矿产品汇入总精矿，为给该选厂工艺流程改善提供指导，从化学组成、元素赋存状态、矿物组成、矿物间的嵌布关系及连生关系等方面，对重选精矿进行了工艺矿物学研究。结果表明：重选精矿铁品位为60.62%，铁主要赋存于赤铁矿和磁铁矿中，主要的脉石矿物为石英；铁主要分布在-0.074 mm粒级，铁在该粒级分布率高达84.47%，TFe品位64.52%，只有通过细磨才能实现铁矿物与脉石的较好解离；在有用矿物与脉石的连生体中，以赤铁矿与脉石结合形成的连生体为主，其次为磁铁矿、赤铁矿与脉石矿物结合形成的连生体；随着粒度变细，试样中赤铁矿和磁铁矿的单体解离度快速提高，尤其在-0.045 mm粒级产品中，绝大多数赤铁矿和磁铁矿颗粒完成了单体解离；赤铁矿和磁铁矿的浸染粒度以中粒、细粒嵌布为主，中粒级试样中脉石含量仍较高，细粒赤铁矿和磁铁矿含量较高，铁主要赋存在-0.074 mm粒级中。建议采用细筛分级-载体浮选工艺进行试验研究，即重选精矿筛上返回再磨，筛下产品进入浮选，背负细粒磁选精矿完成回收。

Process Mineralogy of GravityConcentrate of Anshan Iron Mine

As the iron grade of the gravity concentrate becomes lower in a concentration plant in Liaoning Province， which would not be used as the final concentrate product to integrate into the comprehensive concentrate. Process mineralogy of gravity concentrate is conducted to study in detail from the aspects of chemical composition， element occurrence state， mineral composition， inter-mineral intrusion relationship and continuous relationship， in order to provide guidance for the improvement of the process flow. The results show that the iron grade is 60.62%， and iron in the gravity concentrate is mainly found in hematite and magnetite， and the main gangue mineral is quartz. Iron is mainly distributed in the -0.074 mm grain size. In this grain size the rate of iron distribution is as high as 84.47%， the TFe grade is 64.52%， and iron ore and gangue in gravity concentrate can only be separated by fine grinding. In the combination of useful minerals and gangue， the main combination form is the combination of hematite and gangue， followed by the combination form is the combination of magnetite， hematite and gangue minerals. It was found that the monomer dissociation degree of hematite and magnetite in the sample increased rapidly with the grain size becoming finer. Especially in the -0.045 mm grain size products， the majority of hematite and magnetite particles completed the monomer dissociation. Hematite and magnetite are mainly imbedded with medium and fine grain size. The gangue content in the medium grain size sample is still relatively high， and the content of fine hematite and magnetite is relatively high. Iron mainly occurs in the -0.074 mm grain size. It is suggested that the fine sieving gradation-carrier flotation process is used for experimental research. That is， the gravity concentrate， the product on the screen is returned for re-grinding， the product under the screen enters the flotation and carries fine-grained magnetic separation concentrate to complete recovery.