高铁拜耳法赤泥脱铝提铁研究

    Study on de-aluminization and iron extraction from high-iron Bayer process red mud

    • 摘要: 赤泥是铝土矿提取Al2O3过程中产生的工业废料,其中,高铁赤泥所占比重越来越大,其铁含量高于普通赤泥,因此,对高铁赤泥进行脱铝提铁不仅具有重要的资源回收意义,还能够减轻环境污染。较常见的高铁赤泥脱铝提铁的方法有生物法、物理法、化学法及物理化学联合法。生物提取法通过利用特定细菌及其代谢产物与矿物相互作用,选择性地分离矿物,具有较大的生态友好潜力,但在大规模应用中仍面临技术和经济可行性等挑战。物理分离法操作简单,成本较低,但通过该方法得到的铁精矿品位较低,产品附加价值低。化学分离法可以得到更高品位的铁精矿和更高品质的铝精矿,但其普遍存在工艺流程复杂、能耗高且伴随着环境污染等问题。为进一步优化高铁赤泥脱铝提铁的方法,物理化学联合法成为高铁赤泥脱铝提铁的新兴研究领域,该方法通过还原焙烧-磁选和浸出-磁选等工艺提高赤泥脱铝提铁效果,但依然面临工艺复杂和能耗较高的问题。因此,提出高铁拜耳法赤泥磁化焙烧-碱浸-磁选工艺,实现铝提取与铁同步富集技术,通过对高铁赤泥进行活化来提高脱铝提铁效率的同时,达到减少能耗,简化工艺流程的效果,为赤泥资源化利用提供新的思路。

       

      Abstract: Red mud is the industrial waste produced in the process of extracting Al2O3 from bauxite, of which the proportion of high-iron red mud is increasing, and the iron content of high-iron red mud is higher than that of ordinary red mud, so the de-alumination and iron extraction of high-iron red mud is not only of important significance for resource recovery, but also able to reduce the environmental pollution. The common methods for the removal of aluminum and extraction of iron from high-iron red mud include biological, physical, chemical and combined physical-chemical methods. The biological extraction method, which selectively separates minerals by utilizing specific bacteria and their metabolites to interact with the minerals, has a high potential for eco-friendliness, but still faces challenges such as technical and economic feasibility in large-scale applications. The physical separation method is simple and low-cost, but the iron ore concentrates obtained through this method are of low grade and the added value of the product is low. Chemical separation method can obtain higher grade iron ore concentrate and higher quality aluminum concentrate, but it generally has problems such as complicated process flow, high energy consumption and accompanied by environmental pollution. In order to further optimize the method of iron removal from high-iron red mud, the combined physical-chemical method has become an emerging research field for iron removal from high-iron red mud, which improves the effect of iron removal from red mud through the processes of reduction roasting-magnetic separation and leaching-magnetic separation, but it still faces the problems of process complexity and high energy consumption. Therefore, the process of magnetization roasting-alkali leaching-magnetic separation of high-iron Bayer process red mud is proposed to realize the simultaneous enrichment technology of aluminum extraction and iron. The activation of high-iron red mud can improve the efficiency of de-alumination and iron extraction, reduce energy consumption, simplify the process flow, and provide new ideas for the resource utilization of red mud.

       

    /

    返回文章
    返回