Fundamental Research on an Innovative Fluid-Bed Type Reactor For Fluidization of Ultra-Fine Particles

一种用于超细颗粒流态化的创新型流化床反应器的基础研究

基本信息

批准号：
11305056
负责人：
KATO Kunio
金额：
$ 17.3万
依托单位：
Gunma University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

项目摘要

Cold model experiments were carried out for the development of an innovative fluid-bed type reactor for fluidization of ultra-fine particles. Coarse particles with mean size about 70 μm (FCC particles in Geldart group A) were fluidized with superficial gas velocities 0.5〜1.0 m/s, while fine powders with mean size 0.5 to 15.0 μm (several kinds in Geldart group C) were fed continuously into the dense phase. Investigations were carried out under various operating conditions on the dependent relationship of solid entrainment rate, separation rate of fine particles, and steady state region to fine particles hold-up (weight of fine particles per unit weight of bed particles).When fine particles hold-up was high, fluidization phenomena changed due to formation of particulate aggregate complex for the cases of fine particle sizes less than several μm. Solid entrainment rate increased with decreasing fine particles hold-up, and increasing superficial gas velocity and size of fine particles. Separation rate of fine particles increased with increasing fine particles hold-up, superficial gas velocity and size of fine particles.Tests of continuous feeding of fine particles demonstrated that the operational range was separated into two distinctive ones. One was the region where steady state was maintained, and another was the region where accumulation of fine particles occurred. Steady state operation was impossible when the ratio of discharge rate to feed rate of fine particles fell below unity due to fatal agglomeration in the bed. Steady state operation was also impossible when the size of fine particles was larger than a certain value due to collection of fine particles by cyclone. Hold-up of fine particles in the steady state increased with decreasing superficial gas velocity and size of fine particles and increasing feeding rate of fine particles.

进行冷模型实验，以开发创新的流体型反应器，以用于超细颗粒的流体化。平均大小约70μm的粗颗粒（Geldart A组中的FCC颗粒）用表层气速为0.5至1.0 m/s流动，而平均尺寸为0.5至15.0μm的优质粉末（Geldart组中的几种类型）被连续喂入密集相。在各种操作条件下对固体入口率，细颗粒的分离率以及稳态区域与细颗粒的依赖关系进行研究（床颗粒的每单位重量的细胞重量）。当细颗粒保持高，流动性现象高，由于颗粒粒子的颗粒粒子的形成而变化了，而颗粒粒子的粒子均匀尺寸小于几个μmm，则颗粒的形成。固体入口速率随着细颗粒的降低而增加，表面气体速度和细颗粒的大小增加。细颗粒的分离速率随着细小颗粒的增加，表面气速和细颗粒的大小而增加。细颗粒的连续进料的测试表明，将操作范围分为两个独特的。一个是维持稳态的区域，另一个是出现细颗粒积累的区域。当由于床上致命的聚集而导致的排放速率与细颗粒的进料速率的比率低于统一时，稳态运行是不可能的。当细粒的大小大于旋风收集的细颗粒而大于一定值时，稳态运行也是不可能的。保持稳态的细颗粒的保持增加，随着浅表气体速度的降低和细颗粒的大小以及细颗粒的进食速率增加。