低温还原铁矿微粉过程的数值模拟  

Mathematical simulation of fine iron oxide reduction at low temperature

作　　者：李秋菊[1] 洪新[1] 王兴庆[1] 

机构地区：[1]上海大学,材料科学与工程学院上海200072

出　　处：《材料与冶金学报》2007年第4期243-247,共5页Journal of Materials and Metallurgy

基　　金：国家自然科学基金(No.50474081)

摘　　要：研究了H2在360～400℃之间还原铁矿微粉的过程，并提出了微空间尺度下瞬时气固反应动力学模型，以模拟氧化铁微粉在低温下的还原过程．这个模型包括了非均相化学反应动力学方程、颗粒内的传热方程和气体扩散方程，采用全隐式有限差分方法对控制方程进行数值求解．通过数值计算得到不同颗粒度矿粉在不同温度下还原率随时间的变化，并根据反应热和气体浓度在反应过程中的行为得知化学反应和气体内扩散在反应速率控制过程中所起的作用。数值模拟结果与试验结果基本吻合．In this paper, experiment study was carried out to investigate the reduction of iron oxide in microscale with hydrogen at temperature of 360 - 400 ℃. A transient kinetic model for gas-solid reaction was developed to simulate the behavior of iron oxide reduction at low temperature. The model includes the chemical kinetic equation for heterogeneous reaction, the equations of heat and mass transfers within the particle. The finite difference method with implicit formulation was applied to solve the set of governing equations, from which the variation of reduction ratio of fine iron oxides with different particle size at different temperatures was obtained. The roles of chemical reaction and inner diffusion of gas were also recognized according to the behavior of reaction heat and gas concentration during the reaction process. The results from numerical simulation are consistent with the experimental results.

关 键 词：氧化铁微粉 动力学模型 还原率 低温 气体内扩散 

分 类 号：TF04[冶金工程—冶金物理化学]