An Experiment on Energy Reduction of an Exhaust Air Heat Recovery Type Outdoor Air Conditioning System for Semiconductor Manufacturing Clean Rooms

摘要

In recent semiconductor manufacturing clean rooms, the energy consumption of an outdoor air conditioning system represents about 45 % of the total air conditioning load required to maintain a clean room environment. Meanwhile, there is a large amount of exhaust air from a clean room. From an energy conservation point of view, heat recovery from the exhaust air is therefore useful for reducing the outdoor air conditioning load for a clean room. In the present work, an energyefficient outdoor air conditioning system was proposed to reduce the outdoor air conditioning load by utilizing an air washer to recover heat from the exhaust air. The proposed outdoor air conditioning system consisted mainly of a pre-heater, an air washer, two stage cooling coils, a reheating coil, a humidifier and two heat recovery cooling coils inserted into the air washer and connected to a wet scrubber. It was shown from the lab-scale experiment with outdoor air flow of 1,000 m3/h that the proposed system was more energy-efficient for the summer and winter operations than an outdoor air conditioning system with a simple air washer.