回转窑热工过程仿真与球团平均停留时间的研究  

Research on thermal simulation of rotary kiln and mean residence time of iron ore pellet

作　　者：彭俊[1] 王建辉[1] 谭帅[1] 方晓柯[1] 

机构地区：[1]东北大学信息科学与工程学院沈阳110004

出　　处：《仪器仪表学报》2013年第11期2491-2498,共8页Chinese Journal of Scientific Instrument

基　　金：辽宁省工业攻关计划(2010220014);中央高校基本科研专项资金(N120304004);中国博士后科学基金(2013M530937)资助项目

摘　　要：球团矿链篦机回转窑系统中,由于回转窑的封闭性其窑体内的结圈情况很难了解。通过CFD软件模拟出实际过程中窑内的燃烧情况,通过窑内温度分布得出结圈的形成情况。将结圈导致的窑体内径的变化考虑进模型,结合回转窑的变径函数,对窑内球团流进行定量的受力分析,计算物料在变径情况下的动态休止角,结果显示在结圈作用下,为了使球团处于滚落状态而均匀受热,回转窑转速不得低于0.5 r/min。此外,分段计算出不同进料速率下的料层厚度分布,模拟出回转窑在固定转速下的料层厚度曲线,得出球团平均停留时间。最后,将平均停留时间和温度分布代入球团焙烧强度模型,对比结果显示计算值与现场实际数据吻合。In grate-kiln process for iron ore pellet induration, it is difficult to get the situation of ringing due to the closure characteristic of the rotary kiln. First, the CFD software is used to simulate the actual combustion in the kiln, and the ring formation is learned with further research on the temperature distribution in the kiln. The radius variation of the kiln caused by the ringing forming is considered;taking the radius varying function into account, the force en- dured by the pellets in the kiln is analyzed quantitatively, and the dynamic angle of repose is calculated under the ra- dius variation condition. The result shows that the rotating speed of the kiln must not be less than 0.5 r/min in order to keep the pellets in rolling status during the induration and make the pellets heated uniformly under the ringing forming condition. Then, with radius varying function and the corresponding dynamic angle of repose, the height of the pellets, the height of the pellets in each sub-kiln and the mean residence time （MRT） of the pellets can be ealculat- ed. The height curves of the pellets under different feeding rates are well simulated. Last, the MRT and temperature distribution are substituted into the improved roasting strength model;the comparison result shows that the calculation values well coincide with the actual field measurement data.

关 键 词：燃烧模拟 结圈 平均停留时间 焙烧强度 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]