Applications with semipermeable membranes for humidity recovery in HVAC systems

Both the sensible heat recovery and the combined heat and humidity recovery are state of the art. Of particular importance is the humidity recovery in winter season. The transfer of water vapor from the humidity-laden exhaust air to the very dry fresh air is very important for a good room air quality. However, all systems established on the market require that supply and exhaust air streams crosses within the device. Practical enthalpy recovery systems for plant concepts with local separation of supply and exhaust air are not available on the market until now. In order to close this gap, the ILK Dresden works on a R&D project. The objective is the development of a textile heat exchanger, which - integrated into circulatory composite systems - can transmit not only sensible heat but also humidity between spatially separated air streams. The functional principle is based on a liquid sorption process via semipermeable membranes. The current state of the development will be presented. Furthermore an outlook is given how it is intended to proceed in the project in further steps