Paper No 003 – Comparison on Vacuum Membrane Dehumidification Systems with Moisture Selective Dense Membrane – 13th IEA Heat Pump Conference, Jeju, Korea
Membrane heat pump using vacuum membrane dehumidification (VMD) systems have been investigated recently due to the potential of significant enhancement of energy efficiency. The principal of VMD systems lie in the nature of selective transmission of moisture through dense membrane. The driving force of separation is the vapor pressure gradient between feed and permeate side of a membrane, and the vapor is discharged to the atmosphere through a vacuum compressor. In this paper, performance analysis of three different type of VMD systems – a bypass air mixed type, a water vapor discharge type, and a condenser combined type – are compared to evaluate the performance under same temperature and humidity condition. From the simulation, water vapor discharge VMD shows the best dehumidification COP than others. Further, some conditions like ambient air temperature and relative humidity conditions or minimum vapor pressure difference which are assumed in the basic simulation are varied to simulate in depth. Simulation results are discussed at a practical application point of view.