含铁硅酸盐矿物重构与选择性回收

回收含铁硅酸盐矿物是实现鞍山式贫磁铁矿再选中矿综合利用的关键之一,但这一回收过程应有选择性:一段磁选尾渣TFe仅为3.92%,不予以回收;而二段尾渣TFe为34.51%,可将其返回直接还原配料,予以间接回收。还原温度1150℃、还原时间45 min、石灰石用量16%以及还原煤用量12%时,闭路实验获得的最优粉末铁TFe为92.69%,εFe为91.17%。含铁硅酸盐中铁元素被还原为单质铁,硅元素最终重构为硅灰石。

Reengineering and selective recovery of iron-bearing silicate minerals

The recovery of iron-bearing silicate minerals is a key on the re-separation middlings of Anshan type lean magnetite,but this recovery process should be conducted selectively. The iron grade of stage 1 tailing is only 3.92%,so there is no need to recover it. However,the iron grade of stage 2 tailing is 34.51%,thus this tailing can be returned to the mixing process before direct reduction and its iron is indirectly recovered. Under the condition of the direct reduction temperature of 1150℃,the direct reduction time of 45 min,the limestone dosage of 16% and the coal dosage of 12%,the optimum TFe and εFe obtained from closed-circuit experiment is 92.69% and 91.17%. Iron and silicon in the iron-bearing silicate are reduced to elemental iron and reengineered to aedelforsite,respectively.