焙烧温度对海滨钛磁铁矿直接还原制备钛酸镁的影响  

Effect of roasting temperature on magnesium titanate by direct reduction of seaside titanomagnetite

作　　者：徐承焱[1] 刘伟然 肖晶晶 孙体昌[1] 李召春 XU Chengyan;LIU Weiran;XIAO Jingjing;SUN Tichang;LI Zhaochun(School of Civil and Resources Engineering,University of Science and Technology Beijing,Beijing 100083,China;Chengde Baiquan Iron Mine of Hesteel Group Mining Company,Chengde 271100,China)

机构地区：[1]北京科技大学土木与资源工程学院,北京100083 [2]河钢集团矿业公司承德柏泉铁矿,河北承德271100

出　　处：《中国矿业》2020年第4期89-96,103,共9页China Mining Magazine

基　　金：国家自然科学基金项目资助(编号:51474018,51674018;51874017)。

摘　　要：钛酸镁作为一种优良的介电陶瓷材料,应用广泛。为了提高钛磁铁矿直接还原法制备所得钛酸镁的纯度,研究了不同焙烧温度对海砂弱磁选钛磁铁矿精矿直接还原焙烧生成钛酸镁纯度的影响,并采用扫描电镜和EDS能谱对影响机理进行研究。结果表明,添加80%焦炭的手工生球团在1500℃下恒温焙烧180 min,经磁选可得到产率为21.21%,铁含量为4.35%纯度较高的钛酸镁产品。影响机理研究表明:焙烧温度对钛磁铁矿直接还原制备钛酸镁的影响较大,铁酸镁的含量随着温度的升高呈先增加后急剧下降的趋势,升高温度有利于促进钛酸镁晶体和金属铁的凝聚;当焙烧温度升至1500℃时,焙烧球团中由于还原气氛不足而生成的铁酸镁能够分解,金属铁和钛酸镁颗粒显著长大,且边界分明,有利于后续的磨矿磁选,从而得到更高纯度的钛酸镁。Magnesium titanate is widely applied as an excellent dielectric ceramic material.In order to improve the purity of magnesium titanate prepared by direct reduction of titanomagnetite,the effect of roasting temperature on purity of magnesium titanate generated from direct reduction roasting of titanomagnetite concentrate producing by low intensity magnetic separation of sea sand iron ore is studied,and the mechanism of its influence is studied by using scanning electron microscopy and EDS spectroscopy.The results show that the manual green pellets with 80%coke are roasted at 1500℃for 180 min,and a higher purity of magnesium titanate products with a yield of 21.21%and an iron content of 4.35%are obtained by grinding and magnetic separation.The research of influence mechanism indicated that the roasting temperature had a great influence on magnesium titanate produced by direct reduction of titanomagnetite.The content of magnesium ferrite increased firstly and then decreased sharply with the increase of temperature.The elevated temperature is beneficial to promote the magnesium titanate crystal and aggregation of metal iron.When the roasting temperature is raised to 1500℃,the magnesium ferrite formed in the roasted pellet due to insufficient reducing atmosphere can be decomposed,and the metallic iron and magnesium titanate particles are significantly grown and have a clear boundary,which is favorable for the subsequent grinding and magnetic separation,then,a higher purity magnesium titanate can be obtained.

关 键 词：钛磁铁矿 焙烧温度 直接还原 钛酸镁纯度 

分 类 号：TD923[矿业工程—选矿]