氧化球团微波加热煤基直接还原过程矿相显微结构变化

Mineralogical Micro-structural Changes of Oxidized Pellets during Microwave Heating Coal-Based Direct Reduction

基于常规加热煤基直接还原反应时间长、还原温度高、产品质量差等问题,根据微波加热特性结合直接还原理论提出了一种采用微波能作为加热方式用于氧化球团煤基直接还原的新工艺。在此基础上,通过采用扫描电镜、能谱分析仪等检测手段对微波加热煤基直接还原过程进行了深入的研究,探究氧化球团微波加热煤基直接还原过程显微结构变化规律。研究结果表明,微波加热不仅改变了球团矿的微观结构和能量分配,而且在某种程度上体现了微波加热的"非热效应",从而能够实现渣铁的有效分离,新生金属铁的选择性晶体互连,以及获得高品质的直接还原铁。

In order to solve problems of conventional heating coal-based direct reduction process, such as long reduction time, high reduction temperature and poor product quality, a new coal-baseat direct reduction process of oxidized pellets based on microwave heating characteristics and direct reduction theories in which microwave is used as heating source is proposed. SEM, EDS and other test instruments were used to study the mineralogical micro structural changes of oxide pellets during microwave heating coal-based direct reduction process. Research results show that microwave heating process change micro structure and energy distribution of pellets with non-thermal effect in some extend. In this process, slag and iron are effectively separated, crystals of new metallic iron are selectively connected, and therefore high quality direct reduction iron is obtained.