Heat recovery from kitchen by using range hood with gas-gas plate heat exchanger

The cooking oil fume causes serious health problems, even lung cancer. So, the cooking fume must be removed timely and effectively. Generally, residential range hood removing hot air from kitchen, which contains much heat. However, the heat recovery from kitchen was seldom considered. The gas-gas heat exchanger system is suitable for kitchen heat recovery and it is called heat recovery range hood system. A fresh air fan and a plate heat exchanger are added on common residential range hood to form a heat recovery range hood system, which is proposed in this paper. The system consists of a plate heat exchanger, exhaust air fan and fresh air fan. The exhaust air fan and fresh air fan are the same and fixed in size, so the system size is directly depended on the plate heat exchanger size. In this paper, the thermal design of the heat recovery range hood system is performed by a coupling & epsilon;-NTU method. It shows that the extra exhaust fan increases the heat recovery performance significantly. The decrement of plate spacings at constant overall dimensions of plate heat exchanger also strongly enhances the heat recovery performance.