Liquid desiccant deep dehumidification(LDDD)is an excellent energy-saving technology for low-humidity industries.Ionic liquids(ILs)are favored as optimal working fluids for LDDD,owing to their low vapor pressure,non-c...Liquid desiccant deep dehumidification(LDDD)is an excellent energy-saving technology for low-humidity industries.Ionic liquids(ILs)are favored as optimal working fluids for LDDD,owing to their low vapor pressure,non-crystallization,and non-corrosion.The combined application of IL desiccant with the bubble column has been proven to effectively improve deep dehumidification.The present work focuses specifically on the insights into air-liquid transfer processes in bubble column dehumidifier using ionic liquid desiccant.The effect of operating parameters on volumetric transfer coefficient is examined based on the experimental platform.Meanwhile,the bubble swarms meso-scale flow structure is predicted using computational fluid dynamics coupled with a population balance model(CFD-PBM).Besides,the structure-activity relationship between meso-scale flow structure and transfer performance is investigated.The results indicated a notable phenomenon of bubble aggregation/breakage in the moist air-IL desiccant bubbly deep dehumidification(MA-ILD BDD)system,with a specific interfacial area is basically less than 40 m^(-1).Meanwhile,a decrease in solution temperature,correlated with a significant increase in viscosity,leads to larger turbulent eddies and a slower breakage rate.Notably,a high transfer potential difference enhances heat and mass transfer coefficients at lower solution temperatures,with the mass transfer coefficient at 4℃ being approximately three times that at 10℃.As the superficial velocity changes,the specific interfacial area and heat and mass transfer coefficients have a positive synergistic effect on volumetric transfer coefficient.However,this synergistic effect is reversed with variations in solution temperature.This study aims to clarify the air-liquid transfer mechanism in bubble column dehumidifierusingILdesiccant.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant number 52076039)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant number KYCX23_0270).
文摘Liquid desiccant deep dehumidification(LDDD)is an excellent energy-saving technology for low-humidity industries.Ionic liquids(ILs)are favored as optimal working fluids for LDDD,owing to their low vapor pressure,non-crystallization,and non-corrosion.The combined application of IL desiccant with the bubble column has been proven to effectively improve deep dehumidification.The present work focuses specifically on the insights into air-liquid transfer processes in bubble column dehumidifier using ionic liquid desiccant.The effect of operating parameters on volumetric transfer coefficient is examined based on the experimental platform.Meanwhile,the bubble swarms meso-scale flow structure is predicted using computational fluid dynamics coupled with a population balance model(CFD-PBM).Besides,the structure-activity relationship between meso-scale flow structure and transfer performance is investigated.The results indicated a notable phenomenon of bubble aggregation/breakage in the moist air-IL desiccant bubbly deep dehumidification(MA-ILD BDD)system,with a specific interfacial area is basically less than 40 m^(-1).Meanwhile,a decrease in solution temperature,correlated with a significant increase in viscosity,leads to larger turbulent eddies and a slower breakage rate.Notably,a high transfer potential difference enhances heat and mass transfer coefficients at lower solution temperatures,with the mass transfer coefficient at 4℃ being approximately three times that at 10℃.As the superficial velocity changes,the specific interfacial area and heat and mass transfer coefficients have a positive synergistic effect on volumetric transfer coefficient.However,this synergistic effect is reversed with variations in solution temperature.This study aims to clarify the air-liquid transfer mechanism in bubble column dehumidifierusingILdesiccant.
