精馏分离中的新型中空纤维膜结构填料及其传递现象  

Hollow Fiber Membrane Structured Packing Used in Distillation and its Mass Transfer Phenomena

作　　者：张国亮[1] 孙海敏[1] 陈银飞[1] 何晋浙[1] 

机构地区：[1]浙江工业大学生物与环境工程学院化学与材料工程学院,浙江杭州310014

出　　处：《高校化学工程学报》2008年第2期223-228,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金项目(20476096);浙江省科技计划重点项目(2006C23067;2005C33040)

摘　　要：以异丙醇/水体系为研究对象,采用有挡板的新型聚醚砜中空纤维膜接触器作为精馏结构填料,进行了精馏分离过程和现象的研究。通过不同流动方式的比较,在新型膜接触器中设计了液体管内流动、蒸气壳层沿挡板逆向流动的改进型平行流方式。实验结果表明:无论有无挡板,中空纤维膜结构填料对异丙醇/水溶液的分离效率均较常规结构填料要高得多,且操作气速可以在常规填料液泛线以上,表明其不易受常规填料的操作弹性限制。有挡板膜接触器的性能和分离效率较无挡板时更优,运行参数更为稳定,其最小传质单元高度HTU值可达5.4cm。与其它中空纤维膜分离器类似,其总传质系数K随中空纤维膜的填充密度φ加大而变小,但新型膜接触器精馏过程的总传质系数值较液液萃取要高出约5～10倍。Novel polyether sulfone hollow fiber membrane contactors（HFMCs） with baffles were used as structured packing for the distillation of isopropanol-water solution.During the separation process,a parallel flow mode with liquid flow inside the lumens of the fibers and vapor counter flow outside along baffles were selected after schemes comparison.The results show that,comparing with the traditional packing used for distillation,both baffled and unbaffled HFMCs give better and more productive separation.The baffled HFMCs perform better than the unbaffled ones,especially for higher vapor velocity.The minimal HTU（height of a transfer unit） of the HFMC with baffles could reach as low as 5.4cm,and almost all the HFMCs could work well with the vapor velocity higher than that corresponding to the flooding point of the conventional packing towers.Like most other separators of HFMC,the overall mass transfer coefficient K of the proposed HFMC for distillation decreases with the increase of the fiber packing fraction,while the K of the proposed HFMCs for distillation are about 5～10 times higher than the K of liquid-liquid extraction.

关 键 词：中空纤维膜 结构填料 挡板 异丙醇/水 精馏分离 

分 类 号：TQ028.8[化学工程] TQ051.81