Falling film liquid desiccant dehumidification technology is attracting more and more attention due to lower energy consumption, less pollution, and more flexible humidity control in recent years. This paper conducts a comprehensive review on falling film liquid desiccant dehumidification systems. Firstly, the working principles and features of the liquid desiccant dehumidification are introduced to describe the dehumidification process. The existing liquid desiccants including organic and inorganic desiccants are reviewed. Then, the structures of falling film dehumidifiers including both adiabatic dehumidifiers and internally-cooled dehumidifiers are described. Besides, the simulation models of falling film dehumidifiers, such as finite difference models, effectiveness NTU (ε-NTU) models and simplified simulation models are summarized. Finally, the exiting performance enhancing methods of falling film dehumidifiers are collected, which provide valuable guidance to researchers and engineers to improve the dehumidification performance.
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Dong, C., Hibiki, T., Zhang, L. et al. Falling film liquid desiccant air dehumidification. Exp. Comput. Multiph. Flow 2, 187–198 (2020). https://doi.org/10.1007/s42757-019-0036-8
- falling film
- liquid desiccant dehumidification
- dehumidification performance
- energy consumption