气化渣破碎与预干燥过程数值仿真及实验研究
Numerical simulation and experimental study on gasification slag crushing and pre-drying process
周柏屹 1王浩南 1夏良志1
作者信息
- 1. 大连理工大学化工学院,辽宁大连 116000
- 折叠
摘要
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2～4m/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.
Abstract
Because the gasification slag recovery process is hindered by high viscosity and humidity characteristics,an experimental crushing pre-drying device is built to pre treat 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 mes-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.
关键词
气化渣破碎/气化渣预干燥/CFD-DEM数值仿真/流场分析/离散元分析/气固两相流Key words
gasification slag crushing/gasification slag pre-drying/CFD-DEM numerical simulation/flow field analysis/discrete element analysis/gas-solid two-phase flow引用本文复制引用
出版年
2024
NETL
NSTL
万方数据