A review of electrically driven dehumidification technology for air-conditioning systems

作者：Liu, Hongdou; Yang, Hongquan; Qi, Ronghui^*

来源：Applied Energy, 2020, 279: 115863.

DOI：10.1016/j.apenergy.2020.115863

• Air dehumidification
• Electrically driven
• Electro-osmosis
• Electrodialysis
• PEM-based electrolysis
• Performance

Humidity control is essential for human living environment and industrial production. To overcome the shortcomings of conventional cooling condensation in air-conditioning systems, independent dehumidification such as thermally driven dehumidification (TDD) has been developed for several years. However, TDD systems are still suffered with disadvantages of liquid droplet carryover, large device size, complex system structure, poor flexibility, etc. As a new and promising alternative, electrically driven dehumidification (EDD) has been developed from the 2000s. Different from TDD, EDD uses electric field to remove moisture directly from the air or desiccant, which does not require the low-cost thermal energy necessary in practical TDD systems, making the system more flexible. The DC electricity generated by renewable energy can be directly used in EDD systems. Besides, since there is no rotary wheel or heating equipment, the EDD assembly is more compact, quieter and easier to operate than traditional ones. The EDD system has more advantages in limited-space and high-demand humidity control, such as for wards, precision manufacturing, aerospace equipment, storage of valuables, etc. It also can contribute to the development of distributed energy grids. In this paper, the research progress of EDD is reviewed, including the four kinds of methods proposed in recent literatures: electro-osmosis (EO) solid desiccant dehumidification, electrodialysis (ED) liquid desiccant dehumidification, polymer electrolyte membrane (PEM)-based electrolytic dehumidification, and high-voltage discharge dehumidification. And their working principles, operation performance and optimization methods were summarized and compared. Hybrid or multifunctional EDD systems were also introduced, such as collaboration with photovoltaic modules or joint halogen/hydrogen production during dehumidification, making the system more cost-effective. Finally, a comparison of COP, power supply form, system complexity, air quality, air humidity, and operating temperature between EDD and other dehumidification technologies was conducted. The research gaps and development prospects of EDD were also discussed.