三相强制浆料环流反应器的局部传质行为  

Local Mass Transfer Behaviour in a Three-phase Airlift Loop Reactor with Forced Circulation of Slurry Phase

作　　者：刘梦溪[1] 卢春喜[1] 时铭显[1] 

机构地区：[1]中国石油大学(北京)重油国家重点实验室,北京102249

出　　处：《过程工程学报》2008年第5期845-850,共6页The Chinese Journal of Process Engineering

基　　金：国家自然科学基金资助项目(编号:20676147);国家重点基础研究发展规划(973)基金资助项目(编号:2005CB221205);重油实验室基金资助

摘　　要：提出了一种新型的强制外循环三相环流反应器结构,根据结构特点及流动状态的不同,将反应器分为6个不同的流动区域.在φ300mm×1700mm的实验装置内,采用氧气气提-空气解吸法,详细考察了内环表观气速0.006～0.19m/s、外循环液速0.03,0.05m/s、固含率5%,10%,15%时不同流动区域的体积传质系数.发现外循环液流影响区体积传质系数最大,最高可达0.754s-1,外环环隙区最小,不超过0.043s-1,环流反应器整体体积传质系数与气液分离区体积传质系数接近.适当扩大内、外环截面积比有利于提高环流反应器的传质性能.环流反应器整体体积传质系数随内环表观气速和外循环液速的增加而增加,随颗粒浓度的增加略有降低.A novel three-phase airlift loop reactor with forced slurry phase circulation was proposed. The reactor was divided into six regions. Experiment was conducted in a cold model apparatus with 300 mm ID plexiglas column and 1700 mm in height over a wide range of operation conditions with the superficial velocity in draft tube, UGr, from 0.006 to 0.19 m/s, the liquid velocity pumped into the reactor, Ucir, from 0.0307 to 0.0511 m/s, and the volumetric solid concentration, εs, from 5% to 15%, respectively. The mass transfer coefficient, kLa, was measured in each flow region of the reactor by employing a new O2/air steady-state method. It was found that with kLa as high as 0.754 s^-1, the downcomer affected region has a biggest mass transfer coefficient than other regions, while the annulus region, with kLa no more than 0.043 s^-1, has a smallest one. Interestingly, the mass transfer coefficient of gas-liquid separation region approximately equals to that of whole reactor. In addition, the mass transfer coefficient of whole reactor increases with the increase of superficial gas velocity and superficial liquid velocity pumped into the reactor, but decreases with increasing solid loading.

关 键 词：环流反应器 强制循环液流 流动区域 局部传质行为 

分 类 号：TQ520.5[化学工程—煤化学工程]