还原焙烧—磁选工艺回收马拉维某钛粗精矿中的钛和铁

由于马拉维钛铁矿资源中铁和钛矿物关系复杂，用常规的重选、磁选和电选方法难以直接分离，不能选出合格的钛精矿，仅能获得低品级的钛粗精矿。本研究用MLA(矿物定量自动检测系统)和SEM(扫描电镜)等测试手段对钛粗精矿进行了工艺矿物学研究，研究结果表明，该钛粗精矿中钛赤铁矿和赤铁矿合计含量为16.33%，钛铁矿含量为79.49%，由于钛与铁呈固溶分离或氧化蚀变形成了钛赤铁矿，导致钛粗精矿中钛、铁难以有效分离，因此，采用焙烧工艺将赤铁矿还原成磁铁矿，利用磁铁矿与钛铁矿的磁性差异特征进行磁选分离，有效回收利用钛粗精矿中的铁和钛。钛粗精矿经过还原焙烧—磁选工艺处理后获得铁精矿和钛精矿，铁精矿中Fe含量为56.71%、回收率13.50%，钛精矿中的TiO2含量为49.10%、产率为65.57%、回收率为77.57%。该试验使钛粗精矿中钛铁矿与赤铁矿得到高效分离，为马拉维钛铁矿资源高效综合回收利用提供了技术途径。

Recovery of Titanium and Iron from Titanium Rough Concentrate in Malawi by Reduction Roasting-Magnetic Separation Process

Due to the complexity of iron and titanium minerals in Malawian, only low grade titanium concentrate can be obtained by conventional gravity separation, magnetic separation and electric separation. Through MLA (automatic quantitative analysis system of mineral parameters) and SEM (scanning electron microscope), the process mineralogy of titanium rough concentrate was studied. The results showed that the content of Ti-hematite and hematite in Ti rough concentrate was 16.33%, ilmenite content was 79.49%. It is difficult to effectively separate titanium and iron in titanium rough concentrate due to hematite formed by oxidation and alteration. Therefore hematite is reduced to magnetite by roasting and then magnetic separation is carried out in virtue of magnetic difference between magnetite and ilmenite. Iron and titanium in titanium rough concentrate can be effectively recovered and utilized. Iron concentrate and titanium concentrate were obtained by reduction roasting and magnetic separation process. At the same time, secondary iron concentrate and secondary titanium concentrate were comprehensively recycled. Fe content in iron concentrate was 56.71%, recovery rate was 13.50%. TiO₂ content in titanium concentrate was 49.10%, yield was 65.57%. Fe content in secondary iron concentrate was 51.08%, recovery rate was 10.29%. TiO₂ content in secondary titanium concentrate was 41.51%, yield was 10.57%。The tests solved the technical problem of separating ilmenite from hematite in titanium rough concentrate, and provided a technical way for comprehensive and effective recovery and utilization of Malawian ilmenite.