立磨系统风量对物料重力分级影响模拟分析

摘要

In order to reveal the impact of air volume to gravitational classification to optimize system air volume,MLS3626 vertical mill model was built to take simulated comparison experiments on air volume through the CFD software.The experimental results showed that the more air volume is,the greater velocity of air flow is in gravitational classification,and the bigger velocity gradient is in cross section; particle tracks will be changed with increase of the quantity of air volume,and separation grain size in gravitational classification zone will also become bigger; In grinding process of the cement raw meal,air volume of MLS vertical mill should be kept in 3 500～4 000 m3/min so that velocity field in gravitational classification zone will be better and separation grain size will be more ideal.A test was carried out,which proved that a higher output and better quality of production can be obtained if the air volume of MLS vertical mill was about 4 000 m3/min,which also validated the result of simulation analysis and can pave the way for such a method will be used in vertical mills of pulverized coal and other nonmetallic minerals.%为研究立磨系统风量对物料重力分级的影响,得到系统风量的优化参数,利用CFD流体分析软件对MLS3626立磨进行了以系统风量为单一变量的数值模拟对比实验,实验得出:系统风量越大,重力分级区气体流速越大,该区域截面内速度梯度也越大；增大系统风量,颗粒运动轨迹发生变化,重力分级区切割粒径增大；系统风量在3 500～4 000 m3/min时,重力分级区速度场较优,切割粒径比较理想.通过试验验证了系统风量在4 000 m3/min左右时,产量较高,且质量较好,为此种模拟方法应用到煤粉以及其他非金属矿石的立磨粉磨系统进行风量参数优化奠定了基础.