高温气固流化床的临界流态化行为

Critical Fluidization Behavior of Gas-Solid Fluidized Bed at Elevated Temperatures

本文首先从理论上分析了温度对气固流化床的临界流化速度的影响。并在一个内径为Φ１０５ｍｍ的小型流化床试验装置上测定了不同颗粒在不同温度下的；临界流化速度和临界空隙率。结果表明：小颗粒的临界流态化速度随着温度的升高而减小，大颗粒的临界流化速度随着温度的升高而增加。细颗粒的临界空隙率随温度的升高而增加，中等颗粒的临界空隙率先随温度的升高不断减小，达到一定的温度后再增加；而大颗粒的临界空隙率随温度的变化不很明显。

In this paper,the influence of temperatures on the critical fluidization velocity was analyzed theoretically at first.The critical fluidization velocity and critical bed voidage for different particles at different temperatures were measured in a fluidized bed column with inner diameter Φ105mm.The results show that the critical fluidization velocity for small particles decreases with increasing temperaure,while for large particles, it increases with increasing temperature;the critical bed voidage for small particles increases with increasing temperature;for middle particles,it first decreases with temperature,passes through a minimum and then increases with further increase in temperature;for large particles,it varies little with temperatures.