褐铁矿粉磁化焙烧的实验与模拟研究  

Experiment and Numerical Simulation of Magnetic Roasting of Limonite Powders

作　　者：朱超[1] 杨彪[1] 龚志军[1] 李保卫 武文斐[1] 

机构地区：[1]内蒙古科技大学内蒙古自治区白云鄂博矿多金属资源综合利用重点实验室,内蒙古包头014010

出　　处：《矿冶工程》2015年第5期103-106,109,共5页Mining and Metallurgical Engineering

基　　金：内蒙古应用技术研究与开发资金计划(20130310);内蒙古高校创新团队研究计划(NMGIRT1406);白云鄂博矿多金属资源综合利用国家重点实验室资助项目(BO-13-006)

摘　　要：针对脱水后的多孔褐铁矿,利用同步热分析仪研究了CO在823~873 K之间还原褐铁矿的过程,利用传热、传质与化学反应耦合的动力学模型模拟了微粉磁化焙烧的过程,同时还模拟了孔隙率对焙烧反应的影响。实验结果表明,细颗粒所需的反应活化能更低且反应时间明显缩短。数值计算结果表明,当环境CO浓度由1 mol/m3增大到3 mol/m3时,褐铁矿磁化还原时间减少了73%;褐铁矿颗粒粒径越大,气体越难进入到颗粒内部;模拟和实验结果表明,425μm粗颗粒磁化焙烧所需时间约为75μm颗粒的2.5倍。Aiming at the porosity of dehydrated limonite, reduction of limonite at 823 -873 K with CO was studied by STA. Then, the magnetic roasting process of powder was simulated with a kinetics model that coupled heat and mass transfer with chemical reaction, and the effect of porosity on the roasting reaction was also simulated. The experimental results showed that the activation energy of fine particle reactions was lower and the reaction time was significantly shortened. And the numerical calculation indicated that the reduction time of limonite reduced by 73% when the ambient CO concentration increased from 1 mol/m3 to 3 mol/m3. Furthermore, limonite of larger particle size brought in more difficulty for the gas into the interior of particles. It can be seen from the testing and simulation results that the magnetic roasting time required for the limonite of particle size of 425 μm is 2.5 times as much as that for limonite with size of 75 μm.

关 键 词：褐铁矿 磁化焙烧 数值模拟 

分 类 号：O551[理学—热学与物质分子运动论]