摘要
在一套组合约束型提升管冷态实验装置上,研究了气力输送和快速流态化两种流型下,出口段局部固含率分布规律及不同操作条件对固含率的影响。结果表明:局部固含率径向分布整体上呈中心小、边壁大的分布特征,并随分布器开孔率和表观气速的降低而增大,随上部流化床层压降和颗粒循环强度的降低而减小;在快速流态化操作下,局部固含率曲线分布形式与常规提升管类似,而在气力输送状态下,临近出口区域局部固含率最大值通常不出现在边壁处,其位置随表观气速和分布器开孔率增加以及颗粒循环强度和上部流化床层压降降低而远离边壁;两种流型下局部固含率径向分布的均匀性均随表观气速及分布器开孔率的增加而升高,随颗粒循环强度及流化床层压降的增加而降低。
A cold model of riser with combined restraint was established to study the distribution of local solid hold-up in exit area and the effect of different operating conditions under pneumatic transport and fast fluidization flowing regimes. Experimental results showed that the radial distribution of local solid hold-up was lower in the center region and higher in the wall region. The local solids hold-up increased with the decrease of superficial gas velocity and distributor opening rate, decreased with the decrease of solid flux and upper fluidized bed pressure drop. Under fast fluidization operating conditions, the distribution form of local solid hold-up was similar to that in the conventional riser. Under pneumatic transport operating conditions, the maximum local solid hold-up in exit area didn＇t usually appear in the wall region. The maximum position was away from the wall with the increase of superficial gas velocity and distributor opening rate, the decrease of solid flux and upper fluidized bed pressure drop. Under the two flowing regimes, the radial uniformity of local solid hold-up increased with the increase of superficial gas velocity and distributor opening rate, decreased with the increase of solid flux and upper fluidized bed pressure drop.
出处
《化学反应工程与工艺》
CAS
CSCD
北大核心
2015年第2期97-105,163,共10页
Chemical Reaction Engineering and Technology
基金
国家自然科学基金项目(21106028)
河北省自然科学基金(B2013202125)
关键词
提升管
出口结构
局部固含率分布
气力输送
快速流态化
riser
exit structure
distribution of local solid hold-up
pneumatic transport
fast fluidization
