填充密度对新型中空纤维膜接触器分离性能和传质的影响

Effect of Fiber Packing Density on Performance and Mass Transfer of Hollow Fiber Membrane Contactor

采用聚丙烯中空纤维膜接触器作为新型精馏结构填料对甲醇水溶液体系进行了精馏分离过程的实验研究,探讨了填充密度对中空纤维膜接触器分离性能和过程传质的影响。结果表明,填充密度为4.7%时,接触器塔顶甲醇浓度比填充密度为9.5%时的高,且两种填充密度的膜接触器组件均可在远离常规填料液泛线以上的气速范围操作。随着气速逐步增大,传质单元高度变大,壳程气相传质系数随之变大,填充密度高的组件的气相传质系数较小。

The distillation of aquous methanlol solution was studied using polypropylene hollow fiber membrane contactor as a new type of structured packing and the effects of fiber packing density on separation and mass transfer were investigated. The results showed that when the packing density was 4.7%, the methanol concentration at the top of the membrane contactor was higher than that when the packing density was 9.5%, and the contactor could work well above the limit where flooding normally occurs in conventional cases at different packing densities of fibers. With the increasing of gas velocity, the individual mass transfer coefficient （kG） increased and the height of the transfer unit （HTU） increased. The higher the packing density was, the smaller the kG would be.