河北科技大学学报2025，Vol.46Issue(6)：632-640,9.DOI:10.7535/hbkd.2025yx06005
U形管式流化床中下行段颗粒流动特性研究
Study on particle-fluid flow characteristics in the downer of the U-bend tubular fluidized bed
摘要
Abstract
To address severe pipeline clogging and waste water issues caused by tar condensation during the cooling of raw coal pyrolysis gas,direct catalytic cracking of the hot raw gas from coal pyrolyzer was proposed in this study to convert the polycyclic compounds in tar into low-boiling-point monocyclic compounds.Furthmore,a U-bend tubular fluidized bed was introduced as the cracking reactor.To analyze the particle-flow dynamics in this reactor,a cold-flow model experimental setup was designed and constructed.Axial pressure profiles in both the downer section and riser sections were measured under relatively low bed densities.The effects of solid flux and superficial gas velocity on the axial and radial distributions of solid concentration(the ratio of the total volume of particles to the volume of the reactor)and particle velocity in the downer section were also investigated.The experimental results indicate that the axial pressure in the downer section increases gradually from top to bottom,while the opposite trend occurs in the riser section.In the downer section,the axial solid concentration first rises and then plateaus,exceeding that in a single downer under equivalent conditions.The axial particle velocity decreases in the direction of flow.Radially,the solid concentration exhibits a"dense annular"structure,and the particle velocity declines near the wall.This study offers fundamental insight into the particle hydrodynamics of the U-bend tubular fluidized bed,providing reference for subsequent experimental research and reactor scale-up.关键词
多相流反应工程/荒煤气/流化床/压力/颗粒浓度/颗粒速度Key words
multiphase flow reaction engineering/raw gas/fluidized bed/pressure/solid concentration/particle velocity分类
化学化工引用本文复制引用
马健钧,高德宏,于浩然,王建英,李彦菊,胡永琪..U形管式流化床中下行段颗粒流动特性研究[J].河北科技大学学报,2025,46(6):632-640,9.基金项目
河北省自然科学基金(B2022208045) （B2022208045）
