Performance assessment of a membrane liquid desiccant dehumidification cooling system based on experimental investigations

Chen, Ziwei; Zhu, Jie; Bai, Hongyu

Abstract

A membrane-based liquid desiccant dehumidification cooling system is studied in this paper for energy efficient air conditioning with independent temperature and humidity controls. The system mainly consists of a dehumidifier, a regenerator, an evaporative cooler and an air-to-air heat exchanger. Its feasibility in the hot and humid region is assessed with calcium chloride solution, and the influences of operating variables on the dehumidifier, regenerator, evaporative cooler and overall system performances are investigated through experimental work. The experimental results indicate that the inlet air condition greatly affects the dehumidification and regeneration performances. The system regeneration temperature should be controlled appropriately for a high energy efficiency based on the operative solution concentration ratio. It is worth noting that the solution concentration ratio plays a considerable role in the system performance. The higher the solution concentration ratio, the better the dehumidification performance. However simultaneously more thermal input power is required for the solution regeneration, and a crystallization risk in the normal operating temperature range should be noted as well. The system mass balance between the dehumidifier and regenerator is crucial for the system steady operation. Under the investigated steady operating condition, the supply air temperature of 20.4°C and system COP of 0.70 are achieved at a solution concentration ratio of 36%.

Citation

Chen, Z., Zhu, J., & Bai, H. (2017). Performance assessment of a membrane liquid desiccant dehumidification cooling system based on experimental investigations. Energy and Buildings, 139, https://doi.org/10.1016/j.enbuild.2017.01.046

• Journal Article Type: Article
• Acceptance Date: Jan 14, 2017
• Online Publication Date: Jan 22, 2017
• Publication Date: Mar 15, 2017
• Deposit Date: Jan 17, 2017
• Publicly Available Date: Jan 22, 2017
• Journal: Energy and Buildings
• Print ISSN: 0378-7788
• Electronic ISSN: 1872-6178
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 139
• DOI: https://doi.org/10.1016/j.enbuild.2017.01.046
• Keywords: Liquid desiccant dehumidification, Membrane-based, Evaporative cooling, Experimental study, System mass balance
• Public URL: https://nottingham-repository.worktribe.com/output/850314
• Publisher URL: http://www.sciencedirect.com/science/article/pii/S0378778817301664
• Contract Date: Jan 17, 2017