高铁铝土矿直接还原-石灰烧结过程及机理研究  

Research on ferric bauxite direct reduction-lime sinter process and mechanism

作　　者：胡文韬[1,2] 王化军[1,2] 孙传尧[1,2,3] 刘欣伟[1] 王波[1,2] 

机构地区：[1]北京科技大学金属矿山高效开采与安全教育部重点实验室,北京100083 [2]北京科技大学钢铁冶金新技术国家重点实验室,北京100083 [3]北京矿冶研究总院矿物加工科学与技术国家重点实验室,北京100070

出　　处：《中南大学学报（自然科学版）》2014年第4期1005-1012,共8页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51304012);中国博士后科学基金资助项目(2013M530529);钢铁冶金新技术国家重点实验室开放基金资助项目(KF13-05)

摘　　要：探索基于石灰烧结的高铁铝土矿直接还原方案,并借助XRD,SEM和EDS等手段分析直接还原-石灰烧结过程中的矿物转化机理。研究结果表明:在保温过程中,由于生石灰的反应活性较低,原矿中仅有部分氧化铝矿物转化为碱溶性的铝酸钙。在剩余的氧化铝矿物中,高岭石转化为莫来石,一水硬铝石和一水软铝石转化为刚玉;刚玉和莫来石不溶于碱,造成氧化铝损失。由于石灰烧结反应温度与直接还原反应温度之间存在差异,因此,很难同步实现铝、铁矿物的高效转化。最佳条件为:预磨粒度为<0.038 mm的铝土矿质量分数为74.95%,石灰用量为19.35%,还原温度为1 400℃,还原时间为60 min,最佳试验指标如下:铁品位T(Fe)为71.01%,铁回收率ε(Fe)为99.5%,氧化铝溶出率ηA为61.58%。The investigation of ferric bauxite direct reduction method based on lime sintering technology was conducted. XRD, SEM, and EDS technology were used to reveal mineral phase transition mechanism. The results show that, with a low reactivity, only part of Al2O3 in ore is converted to alkali-soluble calcium aluminate. In the remaining alumina minerals, diaspore and boehmite are converted to corundum, while kaolinite is converted to mullite. Corundum and mullite are alkali-insouble, it results in the loss of alumina. The reaction temperature of direct reduction and lime sinter is different, so it is difficult to recover iron and alumina simultaneously. The optimum conditions are as follows： granularity of pre-grinding 74.95% （particle parameter is less than 0.038 mm）, dosage of lime 19.35%, reduction temperature 1 400 ℃, reduction time 60 min. The best results are T（Fe）71.01%, ε（Fe） 99.5%, and ηA 61.58%.

关 键 词：高铁铝土矿 铁 直接还原 铝铁分离 

分 类 号：TD982[矿业工程—选矿]