拜耳法赤泥磁化焙烧理论与实践问题探讨

Discussion on Theory and Practice of Magnetizing Roasting of Bayer Red Mud

概述了高铁低硅拜尔法赤泥的来源及综合利用现状,介绍了赤泥磁化还原⁃磁选方法以及存在的主要问题,并阐述了赤泥磁化焙烧还原动力学与矿相重构规律。重点介绍了武汉工程大学开发的赤泥多级动态磁化焙烧⁃磁选工艺技术。该技术能得到用于氧化球团的高品质铁精粉和用于制备建筑材料的尾矿,完全消除了结圈结块问题,原料和燃料适应性强、焙烧均匀、温度及弱还原气氛控制方便、能源利用率高,可实现赤泥资源化、减量化、无害化综合利用,具有生产成本低、经济性好、安全环保等诸多优点。

Based on the review of the source and the comprehensive utilization status of high⁃iron and low⁃silicon red mud,the magnetizing reduction⁃magnetic separation of red mud and the problems existed in it were all introduced,and the dynamics of magnetizing roasting for red mud and the principle for mineral phase reconstruction were also discussed.In view of the existing problems,Wuhan Institute of Technology has developed a process consisting of multi⁃staged dynamic magnetizing roasting and magnetic separation.With this technical process,the obtained high⁃grade iron powder can be used for the preparation of oxidized pellet,while the tailings can be used as construction materials.Furthermore,the formation of rings and lumps can be completely avoided.It is found that this technology is characterized by a strong adaptability to raw materials and fuels,uniform roasting process,convenient control of roasting temperature and weak⁃reduction atmosphere,as well as a high energy utilization rate.The practice has proven that this technology can not only realize the comprehensive utilization of red mud based on resources recycling,consumption reduction and harmless exploration,but also bring in low production⁃cost,profitability,safe production,as well as no harm to environment.