A view on the performance comparison between adiabatic and internally-cooled dehumidification processes using liquid desiccant

Abstract

Humidity control is emphasized in various fields. However, the effectiveness comparison between adiabatic dehumidifier (AD) and internally-cooled dehumidifier (ICD) was only conducted in limited cases, without comprehensive understanding of different cooling mediums and working conditions. In this study, the component effectiveness of these two dehumidifiers is parametrically compared. When chilled water serves as cooling medium, AD has sensible effectiveness of 0.65 and latent effectiveness of 0.84 under baseline case, while those of ICD are 0.52 and 0.85 respectively. AD performs better under higher sensible loads, and ICD is more capable of dealing with more moisture transfer. Low water temperature, low air-desiccant ratio and adequately low water-desiccant ratio also highlight the superiority of AD. When secondary air serves as cooling medium, AD always has higher effectiveness than ICD in the studied range, and the superiority is more significant at lower temperature and humidity of secondary air. Sensible effectiveness of 0.44 and latent effectiveness of 0.78 for AD are obtained under baseline case, while those of ICD are 0.07 and 0.74 respectively. ICD has better adaptivity than AD at a circumstance with great variation of operation parameters. The results contribute to enlightening insights for further design of moisture capture components.