A review of membrane-based air dehumidification

Abstract

Air dehumidification plays an important role in improving air quality and maintaining thermal comfort. Increasing attention is paid to the membrane-based technology, which is based on water vapour transmembrane transport driven by mass transfer potential, together with sensible heat transfer under temperature difference. Membrane-based air dehumidification has been applied in heating, ventilation and air conditioning, compressed air dehumidification and environmental control in space vehicle, and some other engineering fields. This paper summarizes recent research results in these fields, including fundamental principles, membrane materials, membrane module structures, operation conditions and theory models. In the end, two methods of membrane-based dehumidification performance evaluation are introduced from perspective of energy and exergy, respectively.

Water vapor permeation and dehumidification performance of poly(vinyl alcohol)/lithium chloride composite membranes

“…Transfer parameters such as permeance and selectivity are dictated by the membrane solubility and diffusivity properties. PVA polymer has been one of the popular choices of material for these membranes due to its hydrophilic properties, stability and ease of film formation [2,8,12,19,23,24,28]. The modification of PVA using lithium chloride to enhance water permeability has been reported [12,19].…”

“…Among them, hydrophilic polymer has attracted much attention due to its high water permeability and selectivity [2,4,[6][7][8]12,[17][18][19][23][24][25][26]. These are usually dense membranes for which water vapor transfer is based on solution-diffusion mechanism.…”

“…Thus far, hydrophilic polymer [1][2][3]6,8,12,[17][18][19], ceramic materials [13] and liquid membranes [14,16,[20][21][22] have been widely used for membrane active layer. Among them, hydrophilic polymer has attracted much attention due to its high water permeability and selectivity [2,4,[6][7][8]12,[17][18][19][23][24][25][26].…”

“…The use of membranes for isothermal dehumidification processes has vast applications in a wide array of industries including heating, ventilation and air conditioning (HVAC) [1,2]; dehydration of flue gas [3][4][5], natural gas [6,7] and organic vapors [8,9]; drying of compressed air [10], steam recovery [9] and air treatment for packaging and processing industries.…”

Next-generation HVAC: Prospects for and limitations of desiccant and membrane-based dehumidification and cooling

“…In recent reviews, Woods 15 and Zhang 16 provided overviews of the latest membrane developments in HVAC and a summary of potential avenues for future research, while another review by Yang et al 17 highlighted the major advances membrane technology has made in air dehumidification. In search of membranes with the greater selectivity necessary to make this process viable, Zhang et al 18 developed a novel membrane using a polyethersulfone (PES) support layer coupled with a polyvinylalcohol (PVA) active layer, while Bui et al 19,20 later reported the fabrication of a robust hydrophilic PVA/LiCl composite membrane.…”