分离膜在膜液体除湿中的应用进展

Application Progress of Separation Membrane on Membrane Liquid Desiccant Dehumidification

由于人们对室内舒适性的要求不断提高,空气除湿技术得到了迅速发展,膜液体除湿因解决了传统液体除湿夹带液滴的问题,近年来得到了广泛的研究与应用。该技术耦合了膜分离技术的选择性与液体除湿的高吸收性,通过选择性透过膜将高湿气体与液体干燥剂隔离开,水蒸气分子在膜两侧水蒸气分压力差的驱动下透过分离膜完成气体的除湿过程。目前,人们对膜液体除湿器中分离膜的膜材料及膜组件进行了大量的研究工作。膜液体除湿器中的膜为气液分离膜,其按材质可分为有机膜、无机膜以及有机-无机复合膜,目前应用在除湿器中的多为有机高分子聚合物膜;而按形态结构可分为微孔膜、致密膜以及复合膜。微孔膜膜孔的润湿现象限制了其应用,因此研究人员对其进行了疏水改性研究。而致密膜则完全避免了这个问题,目前研究者提出了一种吸收器单元思想,为致密膜的下一步研究提供了思路。复合膜性价比比前两种膜结构更高,因此近年来研究人员开发了多种复合膜以用于空气除湿。此外,除湿分离膜可被制成平板式或中空纤维膜式,并分别形成平板膜组件与中空纤维膜组件,为了揭示膜组件内的热湿传递规律,研究人员对两种膜组件内的流体流动方式、共轭传热传质机理、组件结构进行了大量研究,这对膜液体除湿技术的推广及发展具有重要的意义。本文概述了分离膜在膜液体除湿器中的最新研究进展,首先介绍了膜液体除湿器的工作原理,然后归纳总结了分离膜材料在除湿器中的分类及应用,重点介绍了不同形态结构的除湿膜材料,对其性能影响因素及研究进展展开了叙述,接着结合国内外的研究对除湿器中不同分离膜组件的传热传质研究及结构特点进行了概述,最后就分离膜在膜液体除湿技术中的未来研究方向进行了展望。

Due to the continuous improvement of people s requirements for indoor comfort,dehumidification technology has developed rapidly.Membrane-based liquid desiccant air dehumidification technology solves the problem of traditional liquid dehumidification with droplets,and has been widely used in recent years.The technology is coupled with the selectivity of membrane separation technology and the high absorption of liquid dehumidification.The high humidity gas is separated from the liquid desiccant through the selective membrane,and the water vapor molecules are driven by the differential pressure of water vapor on both sides of the membrane to complete the gas dehumidification process through the membrane.At present,researchers have done a lot of research works on the membrane materials and the configuration of membrane components in the membrane liquid dehumidifier.The membrane in the membrane-based liquid desiccant air dehumidification is a gas-liquid separation membrane,which can be divided into organic membrane,inorganic membrane,and organic-inorganic composite membrane according to the material.At present,the organic polymer membrane material is mostly used in the dehumidifier;and morphological structure can be divided into microporous film,dense film and composite film.The application of microporous membranes is restricted by the wetting phenomenon of membrane pores,and researchers have carried out hydrophobic modification studies.The dense film completely avoids the problem,an researcher has proposed an idea of an absorber unit,which provides ideas for the next research of the dense film.Compared with the previous two membrane structures,the composite membrane is more cost-effective.In recent years,a variety of composite membranes have been developed for gas dehumidification.The dehumidification separation membrane can be made into a flat type or a hollow fiber membrane type and formed into a flat membrane module and a hollow fiber membrane module.In order to reveal the heat and moisture transfer law in the membrane module,researchers have studied the fluid flow modes in the two membrane modules.A lot of research has been done on the mechanism of conjugate heat and mass transfer and the structure of the module,which is of great significance to the promotion and development of membrane-based liquid desiccant air dehumidification.The paper summarizes the latest research progress of separation membrane in membrane-based liquid desiccant air dehumidification,first introduces the working principle of membrane liquid dehumidifier,then summarizes the application of separation membrane materials in dehumidifier,mainly introduces the dehumidifier materials with different forms and structures,describes their characteristics and research progress,and then combines the research at home and abroad to different separation membrane groups in dehumidifier.The structure characteristics and the deve-lopment of heat and mass transfer of the components are summarized.Finally,the future research direction of the separation membrane in the membrane-based liquid desiccant air dehumidification technology is discussed.