深度还原分离回收含铌铁尾矿中铌和铁的试验研究

Efficient separation of niobium and iron from tailings of niobium and iron by depth reduction

以某稀土综合尾矿经磨矿-磁选-浮选处理后的含铌铁尾矿为对象,采用深度还原焙烧的方法分离回收铌和铁,研究还原焙烧条件对铌、铁分离效果的影响。结果表明,还原剂种类对铁回收率的影响较为显著,对铌的分离回收影响相对较小,还原剂为褐煤时铁回收率最高;还原时间的延长、焙烧温度的升高以及助熔剂用量的增加均有利于铌、铁的分离回收;在还原剂褐煤用量为10%、助熔剂用量为15%、还原时间为60min、还原温度为1300℃的条件下可实现含铌铁尾矿中铌、铁的高效分离回收,得到w(TFe)为94.82%的铁精矿,铁回收率为99.53%,同时还得到w(Nb2O5)为0.3519%的铌粗精矿,铌回收率为99.62%。

In light of the complex properties of rare earth tailings from magnetic separation and flota-tion ,this paper describes an efficient approach to recovering iron and niobium that uses low-intensity magnetic separation after reduction roasting and studies the influence of reduction roasting parameters on niobium and iron separation .T he results show that the reductant type has a huge influence on iron recovery yet little impact on niobium recovery and w hen the reductant is lignite ,iron recovery is the greatest .The extension of the reduction time ,the increase of roasting temperature and the increase of flux amount have a good effect on iron and niobium separation .When the consumption of the reduc-tant lignite is 10% and that of flux is 15% ,reduction for 60 min at the temperature of 1300 ℃ can a-chieve high-efficiency separation and recovery of niobium and iron from tailings of niobium and iron , with the grade of obtained iron concentrate at 94 .82% ,iron recovery at 99 .53% ,the grade of ob-tained niobium concentrate at 0 .3519% and niobium recovery at 99 .62% .