喷射型环流反应器中气含率和液速的分布  

Gas Holdup and Liquid Velocity Distribution in a Jet Loop Reactor

作　　者：卢浩然 高用祥 成有为[1] 王丽军[1] 李希[1] 

机构地区：[1]浙江大学化学工程与生物工程学院,浙江杭州310027

出　　处：《高校化学工程学报》2017年第5期1088-1095,共8页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金(U1361112)

摘　　要：喷射型环流反应器拥有良好的固体悬浮、液相混合与气液传质性能。在表观气速0.065-0.105 m?s-1的半间歇操作条件下,实验测量了喷射型环流反应器内的气含率以及液速的空间分布。在实验的基础上对反应器进行了三维瞬态的CFD模拟,并且用耦合群平衡模型(PBM)来模拟系统内气泡的聚并破碎行为。喷嘴的高速射流产生一定比例的大气泡驱动液体循环,使循环液速成倍增加。大气泡浮升过程中逐渐破碎成小气泡,导致提升管内的气含率随着轴向塔高增高而增大,降液管中也有类似的分布。实验和模拟都表明,喷射型环流反应器内由于喷嘴的使用导致了分布器影响区的明显延长,不存在流动充分发展的区域。Jet loop reactors have favorable performance in solid suspension, liquid mixing and mass transfer. The distribution of gas holdup and liquid velocity was measured under semi-batch operation conditions with superficial gas velocities ranging from 0.065 m？s-1 to 0.105 m？s-1. 3 D transient CFD-PBM coupled model was utilized to simulate hydrodynamics（especially bubble breakup and coalescence） of the jet loop reactor under experimental conditions. Large bubbles are generated by jetting which significantly enhances liquid circulation. Meanwhile, large bubbles break into small bubbles during rising that leads to the increase of gas holdup along axial position of the riser. Similar processes are shown in the downcomer. Experiments and simulation prove that the size of the sparger zone is remarkably extended due to jetting, and fully developed zones are not observed though the whole reactor.

关 键 词：喷射型环流反应器 分布器影响区 气含率和液速分布 计算流体力学(CFD) 群平衡模型(PBM) 

分 类 号：TQ018[化学工程]