某高铁铝土矿石焙烧—磁选脱铁产物的碱浸—深度脱硅试验  

Alkali Leaching-Deep Desilication Test of Iron Deferring Product from High-iron Bauxite after Roasting-Magnetic Separation

作　　者：梁文娟 邓博纳 叶青 欧阳学臻 余俊杰 Liang Wenjuan;Deng Bona;Ye Qing;Ouyang Xuezhen;Yu Junjie(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China)

机构地区：[1]中南大学资源加工与生物工程学院,湖南长沙410083

出　　处：《金属矿山》2018年第7期118-122,共5页Metal Mine

摘　　要：广西贵港某高铁三水铝石型铝土矿石铁含量达31.76%,Al2O3和Si O2含量分别为21.33%和7.09%,铝硅比为3.01,属典型的高铁、低铝、高硅、低铝硅比的铝土矿石。在常规开发利用工艺难以有效分离铁、铝、硅的情况下,确定采用钠化还原焙烧—磨矿—弱磁选—碱浸—深度脱硅—铝酸钠结晶工艺对该矿石进行开发利用工艺研究,在课题组已报道过焙烧—磨矿—弱磁选工艺的基础上,对富铝渣进行了碱浸与深度脱硅工艺条件研究。结果表明:(1)在富铝渣的碱浸过程中,随着碱初始浓度的增大、浸出温度的升高、浸出时间的延长,铝、硅、铁的浸出率均呈不同程度的上升趋势。碱浓度为200 g/L、浸出温度为220℃、浸出时间为1.0 h情况下的铝、硅、铁浸出率分别为60.51%、6.12%、5.82%。(2)在深度脱硅过程中,随着Ca O添加量的增加,脱硅率逐渐增大;随着温度的升高,脱硅率呈现先上升后下降的趋势;随着反应时间的延长,脱硅率先上升后下降。在Ca O添加量为2 g/L,反应温度为80℃,脱硅时间为2 h情况下,硅的脱除率达90.34%。较好地实现了铝的碱浸和硅的深度脱除。There is a high iron gibbsite-type bauxite ore from Guangxi. The ore is a kind of typical bauxite with high iron content,low aluminum content,low silicon content and the low ratio of alumina to silicon. The iron content of the ore is31.76%,while the content of Al2 O3 and Si O2 is 21.33% and 7.09% respectively,and the ratio of aluminum to silicon is 3.01.Due to the difficulty of effectively separation of iron,aluminum and silicon,the process of sodium reduction roasting-grinding low intensity magnetic separation-alkaline leaching-deep desilication-sodium aluminate crystallization had been used for the development and utilization of the bauxite. On the basis of the process of reported roasting-grinding-magnetic separation process,the conditions of alkali leaching and deep silica removal of aluminum-rich slag were studied. The results showed that：（1）the leaching ratio of aluminum,silicon and iron increased with the increase of initial alkali concentration,leaching temperature and leaching time in the alkali leaching process of aluminum-rich slag. The leaching ratio of aluminum,silicon and iron was 60.51%,6.12% and 5.82% respectively,when alkali concentration was 200 g/L,leaching temperature was 220 ℃ and leaching time was 1.0 h.（2） In the process of deep silicon removal,the desilication ratio gradually increased with the dosage of Ca O increased. As the temperature increased,the desilication ratio was firstly increased and then decreased,and with the extension of reaction time,the desilication ratio was first increased and then decreased. The desilication ratio was 90.34% when the dosage of Ca O was 2 g/l,the reaction temperature was 80 ℃ and the reaction time was 2 h. The alkali leaching of aluminum and deep removal of silicon were well achieved by the process.

关 键 词：高铁三水铝石型铝土矿 碱浸 深度脱硅 综合利用 

分 类 号：TD952[矿业工程—选矿] TF111.31[冶金工程—冶金物理化学]