Li-zhi Zhang
Key Lab of Heat Transfer and Energy Conservation, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
Abstract: Membrane based heat and moisture recovery from ventilation air has become a hot topic for building energy conservation in these years. Over the past 10 years, much work has been conducted in South China University of Technology for the research on this topic, from fundamentals to engineering applications. This paper gives some new developments: the new concepts for membrane heat and mass transfer analysis, the developments of high vapor permeable membranes with finger-like macrovoids, the studies of convective heat and mass transfer in plate-fin ducts, and the application of air dehumidification with membrane based total heat exchangers. The results are that a sensible effectiveness of 0.8 and a latent effectiveness of 0.7 are obtained for a total heat exchanger with novel materials and new constructions. When the total heat exchanger is combined with a fresh air refrigeration dehumidification unit, the system COP is improved to 5.8. Other key issues concerning thermodynamics and transport phenomena in advanced humidity control alternatives will also be introduced.
Keywords: Humidity control; Air dehumidification; Energy recovery; Membranes; Indoor air quality; Heat transfer; Moisture transfer.