以菱镁石为原料铝热还原炼镁的实验研究  

Extraction of Magnesium from Calcined Magnesite by Aluminothermic Reduction in Vacuum

作　　者：王耀武[1] 彭建平[1] 狄跃忠[1] 冯乃祥[1] 李猛[1] 

机构地区：[1]东北大学材料与冶金学院,沈阳110004

出　　处：《真空科学与技术学报》2013年第7期704-708,共5页Chinese Journal of Vacuum Science and Technology

基　　金：辽宁省工业攻关项目(2011221002);辽宁省镁质材料行业高新技术研发项目(MYF2011-34)

摘　　要：对以菱镁石为原料,以铝粉为还原剂的真空热还原炼镁技术进行了实验研究,通过热力学分析和对还原渣的物相分析,对铝热还原煅后菱镁石的机理进行了探讨。还原实验结果表明:当以还原反应4MgO+2Al=3Mg+MgO.Al2O3进行配料时,在还原温度1200℃,还原时间2 h,铝粉过量5%的条件下,氧化镁的还原率在72%以上,铝粉利用率在91%以上,还原过程的实际料镁比低于3.3∶1。进一步提高还原过程的铝粉加入量,可使镁铝尖晶石中的MgO进一步被还原,还原过程中的氧化镁还原率可达85%以上,但铝粉利用率下降至84%左右。The extraction of magnesium metal from calcined magnesite by aluminothermic reduction in vacuum was analytically calculated in thermodynamics,and experimentally evaluated.The influence of the reduction conditions,such as the reduction temperature,reduction time,and excess content of aluminum powder,on the reduction ratio of MgO was evaluated.The microstructures of the slag were characterized with X-ray diffraction and scanning electron microscopy.The results show that if raw reactants were prepared on the basis of the reduction 4MgO＋2Al=3Mg＋MgO＋Al2O3 the reduction rate of MgO and the utilization rate of Al powder were found to be over 72%,and over 91%,respectively,under the reduction conditions：a reduction for 2 h at 1200℃,with an excess Al content of 5%（wt）.The ratio of raw materials to the crude magnesium was estimated to be 3.3∶1.Addition of Al during the reduction were found to further reduce the MgO in MgO·Al2O3,resulting in an increased MgO reduction rate up to over 85%,but a decreased Al utilization rate down to about 84%.

关 键 词：菱镁石 真空铝热还原 镁 镁铝尖晶石 

分 类 号：TF131.1[冶金工程—冶金物理化学]