生物预处理对白云鄂博矿矿石中铌矿物可选性影响机制研究

It is of great significance to explore and utilize Baiyun obo ore as   largest and most rich niobium resources in China. The ore properties of Baiyun obo ore is very complex, so it is difficult to separate. The existing mineral processing technology and the flotation studies of niobium minerals have failed to resolve the low recovery rate and the concentrate grade of the niobium minerals. At present, it is still not ideal for the effect of the niobium minerals flotation which utilized the traditional chemicals to alter the difference of flotability between the niobium minerals and other minerals. Therefore, in this project we will achieve biological modification of the mineral surface with bacteria   to enhance the flotability difference between niobium minerals and other minerals, so the separation effect of niobium minerals was increased. First this project intends to carry out the biological pretreatment for niobite and ilmenorutile using oxidized ferrous sulfur bacillus, then analyze the change of the mineral surface properties and floatability before and after biological pretreatment, and discuss effect mechanism between the bacteria and mineral surface. Then this project will carry out the biological pretreatment for the tailing of rare earth dressing plant in Baotou Steel Group, and analyze how the bacteria act with mineral surface and effect the floatability the tailing of rare earth dressing plant in Baotou Steel Group under complex conditions.

白云鄂博矿作为我国最大最富铌资源，其开发利用具有重大意义。但白云鄂博矿矿石性质 复杂从而增加了分选难度，现有的铌回收选矿工艺与铌矿物的浮选研究都未能解决铌矿物的回 收率及精矿品位低的问题。目前，大多数铌矿物浮选研究采用传统的化学药剂来改变铌矿物与 其它矿物间的可浮性差异，效果仍不理想。因此，本项目拟利用细菌对铌矿物表面进行生物改 性，以增强矿物间的可浮性差异，进而提高铌矿物的分选效果。本项目拟先用氧化亚铁硫杆菌 对铌铁矿和铌铁金红石纯矿物进行生物预处理，通过分析预处理前后矿物表面性质及矿物可浮 性的变化，探讨细菌对铌矿物纯矿物表面性质的影响机制,然后对包钢白云鄂博矿稀选尾矿进 行生物预处理,并分析复杂条件下生物预处理对实际铌矿物表面性质及包钢稀选尾矿中铌矿物 可选性影响的机制。

白云鄂博矿作为我国最大最富铌资源，其开发利用具有重大意义。但白云鄂博矿矿石性质复杂从而增加了分选难度，现有的铌回收选矿工艺与铌矿物的浮选研究都未能解决铌矿物的回收率及精矿品位低的问题。通过对铌铁矿纯矿物的捕收剂浮选试验，研究浮选药剂单一捕收剂及复合捕收剂对铌铁矿纯矿物及人工混合矿浮选的影响，并解析其药剂对铌铁矿纯矿物的作用机理。通过对铌铁矿纯矿物及人工混合矿的抑制剂浮选试验，研究浮选药剂抑制剂对铌铁矿纯矿物与人工混合矿浮选的影响，并解析了抑制剂的抑制作用机理。由于包钢稀选尾矿中铌矿物的品位低，要实现稀选尾矿中铌的利用必须先富集。利用稀选尾矿中稀土矿物、铌矿物和脉石矿物磁性等的不同，通过超导磁选技术实现稀土矿物与铌矿物等矿物的预富集。根据原矿矿石性质确定采用浮选的方法对铌进行回收，探索回收包钢稀选尾矿中铌矿物的工艺。包钢稀选尾矿经过稀土浮选、铌浮选后依然有大量尾矿，尾矿中赋存有类质同象的钪。经微波焙烧的稀选尾矿通过扫描电镜观察发现矿物表面缝隙、裂纹增加，是采用酸浸的办法提取钪的有利因素。重点研究微波焙烧-盐酸浸出方法来提取选铌尾矿中的钪。结果表明: 1）螯合捕收剂与铌铁矿表面的Nb5+生成稳定的-C=O-Nb-O-N-五元螯合物，增加了矿物表面疏水性，提高了矿物的可浮性；2）EDTA在用OHA辛基羟肟酸作为捕收剂浮选铌铁矿的人工混合矿体系中对铌铁矿表面吸附OHA影响较小，相反对脉石具有较强的抑制作用，从而起到了选择性抑制作用。3）超导磁选有效富集了包钢稀选尾矿中铌矿物及稀土矿物；4）稀选尾矿选稀土后在矿浆浓度60%，矿浆温度65℃的条件下选铌，铌品位由0.22%提高到2.62%，作业回收率达到了65.13%。5）铌选别后的尾矿通过微波焙烧—盐酸浸出，钪的浸出率稳定在96.34%。