气固流化床内颗粒的内循环特性的研究

A Study of the Internal Circulating Characteristics of Particles in a Gas solid Fluidized Bed

分析了气固流化床内颗粒内循环产生的原因，进而，分析了流化气体速度、静态床层高度、颗粒粒径以及压力对颗粒内循环的影响。当流化气体速度、静态床层高度和颗粒粒径增加时，颗粒的内循环增强；而压力增大将使颗粒的内循环减弱。当颗粒的内循环增强时，流化床的脉冲信号（ 温度、浓度和灰度等） 响应曲线的振荡加剧，流化床内颗粒的横向混合将得到改善。

On the basis of analyzing the cause of the generation of particle internal circulation in a gas solid fluidized bed further analyzed is the influence on particle internal circulation of the following factors: fluidized gas velocity, static bed layer height and particle diameter and pressure. In case of an increase in the fluidized gas velocity, static bed layer height and particle diameter there emerges an intensification of the particle internal circulation. By contrast, a pressure increase will bring about a weakening of the particle internal circulation. An intensified internal circulation of the particles will result in a drastic increase in oscillation of impulse signal (temperature, concentration and gray scale, etc.) response curves. This can lead to an improvement in the transversal mixing of particles in the fluidized bed.