河北某普通磁铁矿制备超纯铁精矿试验研究

河北某普通磁铁矿TFe品位为65.25%,矿石性质结构简单，具有制备超纯铁精矿的潜力。研究采用多元素及X射线衍射图、物相分析等方法对原矿进行了工艺矿物学研究，并在此基础上对其进行了提纯试验。结果表明，原矿经过弱磁选粗选后，在磨矿细度-0.038 mm占85%的条件下经弱磁选再选、磁选柱精选得到TFe品位为71.31%的磁选柱精矿以及TFe品位68.12%、产率为3.32%的磁选柱铁尾矿。通过进一步考察药剂制度和工艺流程对铁矿精矿品位、回收率等选别指标的影响，确定了合适的药剂制度。而后磁选柱精矿经1粗3精反浮选降硅工艺试验流程，最终可获得含TFe品位71.95%、综合回收率为80.50%的超纯铁精矿，浮选尾矿TFe品位68.17%符合普通铁精矿标准。通过对选别产品进行试样化学成分分析及残余药剂测定，进一步证明该工艺流程可以实现超纯铁精矿的制备。该工艺在抛尾率为10.79%条件下，将原矿样的73.04%转化为超纯铁精矿，对这一地区超纯铁精矿的制备具有重要的指导意义，也为国内其他地区磁铁矿制备超纯铁精矿的研究提供了一定的参考价值。

Experimental study on the preparation of ultra-pure iron concentrate from an ordinary magnetite in Hebei

The TFe grade of an ordinary magnetite in Hebei Province is 65.25%, and the ore properties and structure are simple, which has the potential to prepare ultrapure iron concentrate. In this study, the process mineralogy of the raw ore was studied by multi-element and X-ray diffraction pattern, phase analysis and other methods, and the purification test was carried out on this basis. The results show that after the rough separation of the raw ore with a weak magnetic separation, the magnetic separation column concentrate with a TFe grade of 71.31% and the iron tailings with a TFe grade of 68.12% and a yield of 3.32% were obtained by weak magnetic separation and re-separation and magnetic separation column selection with a grinding fineness of -0.038 mm accounting for 85%. By further investigating the influence of the pharmaceutical system and technological process on the grading and recovery of iron ore concentrate, a suitable pharmaceutical system was determined. Then, the magnetic separation column concentrate was tested by 1 coarse and 3 fine reverse flotation silica reduction process, and finally the ultrapure iron concentrate containing TFe grade of 71.95% and the comprehensive recovery rate of 80.50% was obtained, and the TFe grade of flotation tailings was 68.17%, which met the standard of ordinary iron ore concentrate. Through the analysis of the chemical composition of the samples and the determination of the residual agent, it is further proved that the process can realize the preparation of ultrapure iron concentrate. Under the condition of a tail-throwing rate of 10.79%, 73.04% of the raw ore sample is converted into ultra-pure iron concentrate, which has important guiding significance for the preparation of ultra-pure iron concentrate in this area, and also provides a certain reference value for the research on the preparation of ultra-pure iron concentrate from magnetite in other parts of China.