| 摘要 |
PROBLEM TO BE SOLVED: To prevent water ebullition in heat exchangers for heat recovery during stop of passing water to the heat exchangers for heat recovery, and prevent increase in heat stress in the heat exchangers for heat recovery due to no-water burning and damage resulting from the increase in heat stress, in a heat recovery system recovering heat with compression heat occurring in oil-free type compressors as heating of passing water.SOLUTION: Air coolers 4, 5 cool compression air from compressors 2, 3 with ventilation from fans 4a, 5a. Heat exchangers 6, 7 for heat recovery are provided in an air duct 8 after passing of the air coolers 4, 5, and perform heat exchange between compression air and passing water to heat the passing water. During operation of the compressors 2, 3, in passing water to the heat exchangers 6, 7 for heat recovery, the fans 4a, 5a are stopped or the rotational frequencies of the fans 4a, 5a are decreased, and in stop of passing water to the heat exchangers 6, 7 for heat recovery, the fans 4a, 5a are started or the rotational frequencies of the fans 4a, 5a are increased.SELECTED DRAWING: Figure 1 |
