首页 | 本学科首页   官方微博 | 高级检索  
     

气固并流下行床气体扩散行为的研究
引用本文:魏飞 刘金忠. 气固并流下行床气体扩散行为的研究[J]. 化工学报, 1994, 45(4): 429-434
作者姓名:魏飞 刘金忠
作者单位:清华大学化工系!北京100084,清华大学化工系!北京100084,清华大学化工系!北京100084,清华大学化工系!北京100084
基金项目:国家自然科学基金资助项目
摘    要:采用氢气稳态示踪方法在内径140mm的气固并流下行循环流化床中对气体扩散行为进行了实验研究.实验结果表明:下行床中气体扩散行为可用二维拟均相模型进行描述,其气体的径向扩散系数与气速、固体循环量及颗粒密度的关系可用下列准数关联式表示Pe_r=4.35×10_(-3)Re~(0.95)ε~(-73.4) 1>ε>0.99而下行床中气体轴向扩散系数要比提升管中小1个数量级以上.

关 键 词:并流下行 气体扩散 流化床反应器

GAS MIXING IN A COCURRENT DOWNFLOW CIRCULATING FLUIDIZED BED
Wei Fei,Liu Jinzhong,Jin Yong and Yu Zhiqing. GAS MIXING IN A COCURRENT DOWNFLOW CIRCULATING FLUIDIZED BED[J]. Journal of Chemical Industry and Engineering(China), 1994, 45(4): 429-434
Authors:Wei Fei  Liu Jinzhong  Jin Yong  Yu Zhiqing
Abstract:An experimental study on the gas dispersion behavior of cocurrent downflow gas-solid suspension in a 140 mm i. d. circulating fluidized beds (CDCFB) using the steady-state tracer method is presented. The influence of gas velocity, solids circulating rate and particle density on radial gas dispersion has been examined. Gas dispersion can well be described by eddy diffusion mechanics and a proposed two dimensional dispersed plug- flow model fits the experimental data very well. The correlation Per = 4. 35× 10-3Re0.95ε-73.4(while 1>ε>0. 99) for radial diffusion coefficient is obtained. It is found that the obtained axial diffusion coefficient in the CDCFB is much lower than that in a circulating fluidized bed.
Keywords:cocurrent downflow circulating fluidized bed   gas mixing   steady state tracer  
本文献已被 CNKI 维普 等数据库收录!
点击此处可从《化工学报》浏览原始摘要信息
点击此处可从《化工学报》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号