三水铝石型铝土矿还原溶出赤泥中铁矿物的富集与分离（英文）

研究3种高铁三水铝石型铝土矿的矿物学特征以及不同拜耳法溶出条件对铁矿物富集与分离的影响。结果表明,添加合适的有机物还原剂,例如甘油,可以促进伴生的一水硬铝石,一水软铝石和铝针铁矿的溶出,同时还可以促进针铁矿向赤铁矿转化。利用拜尔法还原溶出处理高铝硅比三水铝石型铝土矿(A/S=25.41)可直接产出合格铁精矿(TFe>56%),实现赤泥的零排放。对于中低A/S的矿石(7.82和3.35),通过重选获得的铁精矿中相应全铁含量分别为52.05%和50.16%,铁回收率分别为65.13%和79.13%,赤泥排放量减少约50%以上。

Enrichment and separation of iron minerals in gibbsitic bauxite residue based on reductive Bayer digestion

The mineralogical characteristics of three kinds of gibbsitic high-iron bauxite and the effects of various digestion conditions on the enrichment and separation of iron minerals were investigated. The results show that adding an appropriate organic reductant such as glycerol can promote the digestion of concomitant diaspore, boehmite and alumogoethite as well as the conversion of goethite to hematite in the reductive Bayer digestion. Processing Bauxite A with A/S of 25.41 can directly produce qualified iron concentrates (TFe>56%) by the reductive Bayer digestion, and thus realize the zero red mud discharge. For Bauxite B and Bauxite C with A/S of 7.82 and 3.35, the iron recoveries of 65.13% and 79.13% can be achieved with the corresponding TFe of 52.05% and 50.16% in the iron concentrates by gravity separation, respectively, resulting in the red mud discharge reduction of ~50% or above.