轴向扩散对中空纤维膜萃取器传质性能的影响  

Effects of Axial Diffusion on the Mass Transfer Performance in Hollow Fiber Module Extractor

作　　者：王玉军[1] 骆广生[1] 王岩[1] 戴猷元[1] 

机构地区：[1]清华大学化学工程系,北京100084

出　　处：《化学工程》2002年第4期52-55,共4页Chemical Engineering(China)

基　　金：国家自然科学基金项目 (No .2 9836 130 )

摘　　要：通过测量聚丙烯中空纤维膜萃取器壳程和管程流动的RTD曲线 ,证实了中空纤维膜器管程与壳程流动均较为复杂 ,与理想平推流和理想全混釜相差较大。膜器管程流动的轴向返混程度随着流速增加而减小 ,而膜器壳程流动的轴向返混程度随着流速的增加而增大。将两相流轴向扩散模型用于描述传质情况 ,比较了表观传质系数和真实传质系数 ,计算了中空纤维膜萃取器中真实的浓度剖面。结果表明 ,中空纤维膜萃取器轴向扩散导致表观传质系数比真实传质系数下降 30 %左右 ,所以在进行膜器设计和放大时 ,中空纤维膜器的轴向扩散不可忽略。The flow status in hollow fiber module extractor was comprehensively studied by measuring the resident time curves. The axial diffusion model was applied to describe the non-ideal flow in tube side and shell side. It was found that the actual flow was different from that of ideal plug and continuously stirred tank. The calculated curves by axial diffusion model agreed well with the actual RTD curves. The axial diffusion in tube side decreased with the increasing of flow velocity, while the axial diffusion in shell side increased with the increasing of the flow velocity. Using 20% triotylamine + 30% octanol + 50% kerosene, p -amine sulfanilic acid and water as experimental system, the influence of the axial diffusion on mass transfer in hollow fiber module extractor was further studied. The experimental results indicated that the great decrease of the mass transfer performance was caused by the axial diffusion.

关 键 词：轴向扩散 中空纤维膜 萃取器 传质性能 影响 膜萃取 模型 

分 类 号：TQ028.8[化学工程]