武钢球团矿还原反应动力学  

Reduction kinetics of pellets from Wuhan Iron and Steel Corporation

作　　者：李鹏[1] 毕学工[1] 张慧轩[1] 周进东[1] 

机构地区：[1]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,湖北武汉430081

出　　处：《钢铁研究学报》2015年第11期8-13,共6页Journal of Iron and Steel Research

基　　金：国家自然科学基金资助项目(51174149)

摘　　要：采用热失重法在900～1100℃的范围和CO的体积分数为100％的气氛条件下，对武钢球团矿进行恒温还原实验，通过阿伦尼乌斯（Arrhenius）图和未反应核模型公式分别计算了还原反应的表观活化能和反应速率常数、扩散系数，并判断反应速度的限制性环节，使用场发射扫描电子显微镜（FESEM）和能谱分析（EDS）观察了球团矿在还原过程不同阶段的微观形貌和铁的氧化物的形式，分析了球团矿的反应机理。结果表明：在球团矿还原反应前期至中后期的大部分时问内，反应的限制性环节为界面化学反应，而后期限制性环节改变为固相扩散；球团矿还原是按照铁的氧化物从高级到低级的顺序进行的，采用未反应核模型进行动力学分析是正确的。Isothermal reduction experiments of the pellets from Wuhan Iron and Steel Corporation （WISC（）） were performed with the thermogravimetry technique in the temperature range from 900 ℃ to 1 100 ℃ and under the at mospherc of CO of 100% （volume fraction）. The apparent activation energy, reduction rate constant and diffusion coefficient were calculated in terms of the Arrhenius plots and the unreacted core model, respectively, and the rate controlling steps were ascertained accordingly. The microstructure and forms of iron oxides of the pellets at the different reduction stages were observed by FESEM and EDS techniques and the reduction reaction mechanism of the pellets was analyzed accordingly. The results show that the controlling step of the reduction reaction of the pellets is the interfacial chemical reaction during most of the time from the initial stage through the middle and later stage, and it shifts to the solid diffusion at the final stage, and that the pellets reduction proceed in the order from higher oxides to lower oxides of iron and the application of the unreacted core model to the kinetic analysis is appropriate.

关 键 词：球团矿 还原动力学 阿伦尼乌斯图 未反应核模型 

分 类 号：TF046.6[冶金工程—冶金物理化学]