The invention discloses an air dehumidifier based on composite
microporous membranes. The air dehumidifier comprises end sockets, flanges, a longitudinally long middle tube shell structure, a pillar,connectors, cold water inlet and outlet flow passages, and air inlet and outlet flow passages. The two end sockets are used for fixing two ends of each membrane filament, and are respectively connected to the cold water inlet and outlet flow passages through the connectors and the flanges so that low-temperature cold water flows into the membrane filaments. The tube shell structure contains a plurality of clustered hollow
fiber composite microporous membrane filaments, and is hermetically connected to the end sockets at two sides. The pillar disposed in the center axis of the tube shell structure is a supporting structure, ensuring that the membrane filaments have sufficient
mechanical strength, and that the low-temperature cold water flows into the membrane filaments, exchanges heat withhigh-temperature high-
humidity air fed and discharged from the air inlet and outlet flow passages arranged on the side surface of the tube shell structure, and then is conveyed into a sealing bin foruse. According to the air dehumidifier, temperature and
humidity of wet air are reduced, and under combined functions of capillary force in micropores of the membranes and the
water vapor partial pressure difference, transmission of
water vapor to the cold water is achieved, and the
water vapor valuable in a
spacecraft cabin can be directly completely recovered.