出口结构对循环流化床锅炉床内轴向密度的影响

针对目前工业循环流化床锅炉存在的主要问题(床温控制、细颗粒的停留时间及气固横向混合)及其工程对策的缺陷,用试验方法探索利用改变出口结构来增加颗粒的内循环;研究了多种循环流化床的出口几何结构在不同操作条件下对床内流动特性的影响机理。试验表明,循环流化床锅炉出口几何结构对床内轴向密度的影响很大,选择合理的出口几何结构,可以在循环流化床锅炉运行条件范围内增强床顶部甚至全床的床密度,增强颗粒的内循环,从而增加颗粒在床内的停留时间。

The Efect of the Exit Configurations on the Bed Density of the Circulating Fluidized Bed Axial Boiler

This article mainly introduces the advantages and the shortages of the circulating fluidized bed boilers,also counter the main problems of present circulating fluidized bed boilers and the shortcoming of their engineering countermeasures,and explores how to enhance the in- ternal circulation with changing the exit configurations by experiment.This article studies the in- fluence of manifold exit configurations on the hydrodynamics characteristics,and explain the mechanism of this influence.The experiments show that bed exit geometric configurations greatly influence the bed axial density in fluidized bed boilers.The experimental results make clear that the bed axial density increases in the upper part,even in the whole bed by using the rational exit configuration.It may enhance the internal circulation,thus to increase the residence time of par- ticles in bed.