Energy saving potential of adiabatic humidification with pressurized water atomizer in HVAC system for semiconductor cleanrooms

Abstract

This paper is aimed to evaluate the applicability of an adiabatic humidification in heating, ventilation, and air conditioning (HVAC) systems for semiconductor cleanrooms. The accurate temperature and humidity control are essential in semiconductor cleanrooms and a steam humidification is commonly used with lots of energy consumptions. Therefore, we proposed an adiabatic humidification employing a pressurized water atomizer to reduce the energy consumptions. The annual energy consumption of three different HVAC systems were analyzed to evaluate the applicability of the adiabatic humidification. The studied cases are as follows: 1) a make-up air unit (MAU) with a steam humidifier, a dry cooling coil (DDC), and a fan filter unit (FFU); 2) a MAU with the pressurized water atomizer, a DDC, and a FFU; and 3) a MAU, a DCC, and a FFU, and the pressurized water atomizer installed in the return duct. The results showed that the HVAC system containing the MAU, DCC, FFU, and the pressurized water atomizer in the return duct has the lowest annual energy consumption due to the energy savings from the pressurized water atomizer. In addition, the pressurized water atomizer has a greater energy conservation potential when installed in the return duct.