Paper No 355 – Performance Test of Dense Membrane for Vaccum Membrane Dehumidification System – 13th IEA Heat Pump Conference, Jeju, Korea
A membrane mass exchanger where water vapor is exchanged in a vacuum membrane dehumidification (VMD) system utilizes the vapor pressure difference between the permeate side and the feed side. However, differently from a typical moisture selective membrane, this membrane is located under pressure difference to accelerate the separation. Thus, a new approach to validate performance of the water vapor selective membrane is required. In order to quantitatively measure the effect of this phenomenon on the moisture permeability, an experimental system was setup to measure water vapor selectivity and permeance under the presence of absolute pressure difference before and after the membrane. So far, it is known that the performance of membrane is only a function of partial pressure of vapor. However, from the experiment, it is observed that selectivity and permeance are also changeable by absolute pressure difference due to the physical deformation caused by absolute pressure difference across the membrane.