微波加热含锌粉尘的物相形貌特征及还原过程研究

Research on Phase Morphology and Reduction Process of Dust Containing Zinc Heated by Microwave

含锌粉尘和煤粉按质量比4:1混合形成混合粉。采用化学分析和扫描电镜对混合粉的成分和物相进行分析,研究大气常压下微波加热还原混合粉在不同时间下的显微物相形貌特征以及混合粉的还原过程。结果表明:微波加热7 min时,混合粉物相中出现金属铁相、浮氏体相和渣相;随时间的延长,金属铁相逐渐增大、浮氏体相逐渐减小、渣中的锌含量逐渐减少,20 min时,浮氏体相消失,渣中已很难找到锌元素;混合粉的脱锌率和金属化率随加热时间的延长不断提高,加热20 min,金属化率均能达到80%以上,脱锌率在前10 min提高明显,能达到67%。

The mixed powder is formed by zinc dust and coal as a mass ratio of 4：1.The phases and composition of zinc dust were analyzed by chemical analysis and scanning electron microscopy.The phase morphology and reduction process of zinc dust heated by microwave in different periods were studied,no gas protection and atmospheric pressure.Results show that the phases of metallic iron,wustite and slag appear when heated by microwave for 7min; with the time increasing,metallic iron phases are growing up,wustite phases are decreasing and the zinc content of the slag is reducing.While the time is 20min,the wustite phases disappear and it is hard to find zinc in slag; metallization and dezincification increase with the increase of time and reach a minimum of 80％at 20min,and the dezincification increases significantly and achieves 67％ in the furst 10min.