内配碳固态还原钒钛磁铁矿试验研究

Experimental Study on Solid-state Reduction of Vanadiferous Titanomagnetite Ore with Carbon Containing Pellets

对内配碳-电炉固态还原-球磨-强磁选-尾矿酸化氧化浸出五氧化二钒工艺进行了研究,讨论了不同的还原剂以及还原剂用量、还原温度、还原时间等因素对固态还原钒钛磁铁矿的影响。研究结果表明,最佳的工艺参数为:有机粘结剂用量为2%、无烟煤还原剂用量为矿量的30%、还原时间60 min、还原反应温度1 200℃、磁选场强0.12 T、磁选尾渣浸出硫酸浓度为25%、液固比4∶1、氯酸钠氧化剂用量为尾矿质量的5%、浸出温度为常温、浸出时间180 min。此条件下,磁选铁精矿经800℃氢还原30 min后,所得铁粉金属铁品位大于96%,达到化工铁粉质量要求。磁选尾渣经氧化浸出后,溶液中五氧化二钒的浸出率大于76%,浸出渣即钛精矿品位大于37%。

The processing flowsheet consisting of preparation of carbon-containing pellets for vanadiferous titanomagnetite ore, solid-state reduction, ball , high-intensity magnetic separation, oxidizing leaching of tailings under acidic condition, results in the product of vanadium pentoxide. Influence over solid-state reduction of vanadiferous titanomagnetite ore by those factors including different reductant, reductant dosage, reduction temperature and reduction time were all discussed. The results show the reasonable conditions are determined as follows： the dosage of organic binder is 2%, the amount of reductant （anthracite） is 30% of total feed, the reduction temperature is 1 200 ~C, the reduction time is 60 mins and the magnetic field intensity is 0.12 T, concentration of H2SO4 for leaching taillings slag from magnetic separation is .25% with a liquid-solid ratio of 4： 1, the dosage of sodium chlorate oxidant is 5% of tailing mass, the leaching temperature is room temperature while the leaching time is 180 mins. Under this condition, reduction of iron concentrate in hydrogen at 800 ~C for 30 mins resulted in the iron powder with TFe grade more than 96%, meeting the quality standard of iron powder for chemical industry. Tailings from magnetic separation was subjected to oxidizing leaching, resulting in the leaching rate of vanadic oxide greater than 76% and the grade of ilmenite concentrate greater than 37%.