A multi-stage structure packing tower dehumidifier for feed air dehumidification in compressors is proposed to reduce the power consumption of compressors in cryogenic air separation systems. A multi-stage cooling and dehumidification experimental bench was built

and the dehumidification performance of the dehumidifier was examined experimentally. Experimental results indicated that when the air flow rate increased from 0.48 kg/s to 0.78 kg/s

the moisture content at the air outlet increased from 7.1 g/(kg dry air) to 7.7 g/(kg dry air) with the inlet moisture content and temperature maintained at 11.7 g/(kg dry air) and 24.4 °C

respectively. When the cooling water temperature increased from 6.9 °C to 11.9 °C

air outlet moisture content increased from 7.1 g/(kg dry air) to 9.4 g/(kg dry air) with the inlet air flow rate and temperature maintained at 0.53 kg/s and 25.2 °C

respectively. A steady-state numerical model of heat and mass transfer process in the dehumidifier was established and verified using the experimental data. A performance study of the multi-stage structure dehumidifier and single-stage cross-flow structure dehumidifier was conducted based on the numerical model. The results indicated that the dehumidification rate and dehumidification efficiency can be increased by 4.3% and 2.5%

respectively with the inlet air flow rate and water flow rate maintained at 0.53 kg/s and 0.3 kg/s

respectively. Additionally

the dehumidification performance can be improved by increasing the length of the packing module. The volume of the packing module was fixed at 0.054 m3.Hence

when the module length increased from 0.14 m to 0.28 m

the mass transfer coefficient increased from 4.3 g/(m2?s) to 6.5 g/(m2?s)

and the dehumidification efficiency increased from 66.4%to 79.2%.