为解决气化渣回收过程受高黏湿特性阻碍的问题,通过搭建实验级破碎和预干燥装置对其进行预处理,结合实验和单向CFD-DEM数值仿真研究了不同因素对气化渣破碎和预干燥效果的影响。结果表明,流场速度随转子转速增加而明显上升,但随着进气速度增加上升幅度减小。建模颗粒团尺寸确定为2 mm,随转子转速增加,颗粒与转子碰撞强度增大,运动速度为2~4 m/s的颗粒数量增多,破碎率升高;随进气速度增加,对颗粒的扰动作用增强,破碎率小幅增加;随进料量增加,颗粒与转子的碰撞强度下降到一定程度后趋于稳定,低速运动的颗粒数量急剧增加,破碎率降低。随进气速度和进气温度的增加,热风对颗粒的传热效果增强,出料温度升高;进气速度增加能有效减少低温颗粒的数量,进气温度升高对颗粒的升温效果影响有限。数值仿真和实验结果为气化渣的大规模工业化处理提供了理论参考。

Because the gasification slag recovery process is hindered by high viscosity and humidity characteristics,an experimental crushing pre-drying device is built to pretreat the gasification slag.The influences of different factors on the crushing and pre-drying effects of gasification slag are studied through experiment and one-way CFD-DEM numerical simulation.Results show that the velocity of the flow field increases obviously with the increase of the rotor speed,but the increase becomes small with the increasing inlet velocity.The size of the modeled particle cluster is determined to be 2 mm.With the increase of the rotor speed,the collision strength between the particles and the rotor enhances,the number of particles with a moving speed of 2-4 m·s^-1 rises,and the crushing rate also rises.With the higher inlet velocity,the disturbance effect on particles enhances,and the crushing rate rises slightly.With the increasing feed rate,the collision strength between particles and rotor declines to a certain extent and then tends to be stable,the particles moving at low-speed sharply becomes more,and the crushing rate drops.With the increasing inlet velocity and inlet temperature,the heat transfer effect of hot air on particles is enhanced,and the discharge temperature lifts up.Higher inlet velocity can effectively reduce the number of low temperature particles,and higher inlet temperature has little effect on the heating effect of particles.The numerical simulation and experimental results provide a theoretical reference for the large-scale industrial treatment of gasification slag.

周柏屹(1999-),男,硕士生,研究方向为气化渣破碎和干燥处理,zboy@mail.dlut.edu.cn;夏良志(1967-),男,博士,教授,博士生导师,研究方向为油页岩、褐煤等干燥预处理的流态化技术及装备,通讯联系人,xlz@dlut.edu.cn。