A thermodynamic perspective to study energy performance of vacuum-based membrane dehumidification
Type
ArticleKAUST Department
Biological and Environmental Sciences and Engineering (BESE) DivisionEnvironmental Science and Engineering Program
Water Desalination and Reuse Research Center (WDRC)
Date
2017-05-13Online Publication Date
2017-05-13Print Publication Date
2017-08Permanent link to this record
http://hdl.handle.net/10754/623626
Metadata
Show full item recordAbstract
In humid environments, decoupling the latent and sensible cooling loads - dehumidifying - can significantly improve chiller efficiency. Here, a basic limit for dehumidification efficiency is established from fundamental thermodynamics. This is followed by the derivation of how this limit is modified when the pragmatic constraint of a finite flux must be accommodated. These limits allow one to identify promising system modifications, and to quantify their impact. The focus is on vacuum-based membrane dehumidification. New high-efficiency configurations are formulated, most notably, by coupling pumping with condensation. More than an order-of-magnitude improvement in efficiency is achievable. It is contingent on water vapor exiting at its saturation pressure rather than at ambient pressure. Sensitivity studies to recovery ratio, temperature, relative humidity and membrane selectivity are also presented.Citation
Bui TD, Kum Ja M, Gordon JM, Ng KC, Chua KJ (2017) A thermodynamic perspective to study energy performance of vacuum-based membrane dehumidification. Energy. Available: http://dx.doi.org/10.1016/j.energy.2017.05.075.Sponsors
The authors gratefully acknowledge the generous funding from the National Research Foundation (NRF) of Singapore under the Energy Innovation Research Programme (EIRP) Funding Scheme (R-265-00-543-279) managed on our behalf by the Building and Construction Authority (BCA). JMG expresses his gratitude to Prof. Kian Jon (Ernest) Chua for his generous and gracious hospitality at NUS during the period of this research.Publisher
Elsevier BVJournal
EnergyAdditional Links
http://www.sciencedirect.com/science/article/pii/S0360544217308289ae974a485f413a2113503eed53cd6c53
10.1016/j.energy.2017.05.075