催化裂化汽提器内颗粒停留时间分布的数值模拟  

Numerical Simulation of Solids Residence Time Distribution in Fluid Catalytic Cracking Strippers

作　　者：刘英杰[1] 蓝兴英[1] 徐春明[1] 高金森[1] 

机构地区：[1]中国石油大学重质油国家重点实验室,北京102249

出　　处：《石油化工》2010年第11期1215-1220,共6页Petrochemical Technology

基　　金：国家杰出青年基金项目(20725620)

摘　　要：采用计算流体力学数值模拟方法对空筒型和人字形挡板汽提器内的气固两相流动进行模拟,模拟中采用示踪技术得到了催化剂出口处颗粒的停留时间分布,采用死区模型对停留时间分布曲线进行分析,得到了两种汽提器内的死区、活塞流区及全混流区的体积分数。模拟结果表明,人字形挡板汽提器的死区体积约为10%,活塞流区体积大于40%,全混流区体积小于50%;空筒型汽提器的死区体积占反应器体积的15%～35%,活塞流区体积为10%～25%,全混流区体积为50%～60%;人字形挡板汽提器能够减小死区体积及全混流区体积,增大活塞流区体积,从而提高汽提器体积的利用率,降低颗粒的返混程度,提高汽提效率。The flow behavior in the fluid catalytic cracking strippers with and without internals was simulated using computational fluid dynamics. The residence time distributions （RTD） of the catalyst solids were obtained at the catalyst outlet by coupling the tracer technique. The dead volume model was applied to analyze the RTD curves of the solids. The fractions of the dead, plug and well-mixed volumes in different strippers were compared. In the V-baffled stripper, the dead volume fraction is about 10%, the plug volume fraction is above 40% while the well-mixed volume fraction is below 50%. In the empty cylinder stripper, they are 15%-35%, 10%-25% and 50%-60%, respectively. The results demonstrate that in the V-baffled stripper, the stripping volume is utilized more sufficiently and the solid back-mixing is lowered, which will finally improve the stripping efficiency.

关 键 词：催化裂化 汽提器 停留时间分布 死区模型 汽提效率 

分 类 号：TQ018[化学工程]