Energy conservation with tumbler drying in laundries

While the enegy consuming process of drying paper, textiles and construction materials during manufacturing has warranted a large number of studies, the more dispersed everyday activity of laundry drying seems not to have awakened as much interest, This is perhaps because laundry drying installations are usually either domestic or comparatively small. Nevertheless, the energy used for laundry drying represents 0.5% of the total electrical energy use in Switzerland for example, and that figure is bound to be still higher in other countries. In this article it is demonstrated that conventional tumbler dryer technology is susceptible to improvement by the use of heat recovery heal exchangers. The energy recovery potential may be as high as 20% of that required for heating the drying air. The additional investment required for the heat recovery heat exchanger is paid back in less than two years of normal use. (C) 1997 Published by Elsevier Science Ltd.