不同磁浮工艺对综合回收某稀土尾矿中稀土、铁、铌和萤石的影响

Recovery of Rare-Earth,Iron,Niobium and Fluorite in Rare-Earth Tailings with Different Magnetic Separation and Flotation Technologies

对某稀土尾矿进行了不同磁浮工艺综合回收稀土、铁、铌和萤石的试验研究,研究了不同工艺对4种有价成分回收率的影响,并采用扫描电镜(SEM)、X射线衍射(XRD)等手段对稀土尾矿、铌铁焙烧产物进行测试。结果表明,4种有价成分金属含量主要分布在细粒级和微细粒级中,并与其他脉石矿物呈包裹体和连生体形式存在。稀土尾矿在分选稀土和萤石时,磁选工艺优于浮选工艺;分选铌和铁时,还原焙烧-弱磁工艺优于磁浮联合工艺,其中弱磁性铁矿物经还原焙烧成为单质铁;弱磁-强磁-浮选-焙烧-弱磁工艺流程适合于高效回收稀土尾矿中的4种有价成分,稀土尾矿经弱磁预先分离磁铁矿,弱磁尾矿经过强磁、浮选和还原焙烧-弱磁工艺,分别得到铁、稀土、铌和萤石粗精矿的回收率可达61.55%,57.33%,47.96%和56.14%,达到了综合高效回收的目标。

For the comprehensive recovery of rare-earth,iron,niobium and fluorite,different processes of magnetic separation and flotation were introduced to the rear-earth tailings. The research was to study the influence of different technologies on the recovery rate of the four kinds of minerals. Scanning electron microscopy（ SEM） and X-ray diffraction（ XRD） analysis were used to analyze the rare-earth tailings and the roasted products of niobium and iron. The results showed that the metal content of the four minerals was mainly distributed in the fine fraction and micro-fine particles,and presented as the inclusions or the intergrowth form with other gangue minerals. High intensity magnetic separation was better than flotation in the separation process of rare-earth and fluorite; reduction roasting-low intensity magnetic separation was better than magnetic separation and flotation process in the separation process of niobium and iron,while the weak magnetic iron ore became pure iron by reduction roasting; low intensity magnetic separation-high intensity magnetic separation-flotation-reduction roasting-low intensity separation was suitable for the efficient recycling of the four kinds of valuable minerals from the rare earth tailings. The magnetite was separated by low intensity magnetic separation in advance from rare-earth tailings. And the weak magnetic tailings were treated by high intensity magnetic separation,flotation and reduction roasting-low intensity magnetic separation. The rough concentrate recovery rate of iron,rare-earth,niobium and fluorite reached 61. 55%,57. 33%,47. 96% and 56. 14%,respectively,which met the goal of efficient recycling.