| 摘要 |
PURPOSE:To prevent adhesion of scales and obtain the heat exchanger free of maintenance by a method wherein a direction switching valve is provided in the flow paths of the heat exchanger for geothermal water and fresh water while the passages in the heat exchanger are switched alternately at every predetermined times. CONSTITUTION:In the heat exchanger 1 of plate fin type or the like, the direction switching valve 2 is provided at the inlet sides of two fluid paths 3, 4 and the geothermal water and the cool fresh water are flowed through respective paths 3, 4 alternately periodically. In case the heat exchange is effected between the geothermal water, containing much of soluble SiO2, and city water to obtain hot-water having a temperature of 40 deg.C for one month under switching the flow paths at every two days, the adhesion of scales may be reduced to substantially one third compared with the case in which the switching of the flow path is not effected. In case the heat exchange is effected under utilizing the geothermal water containing much of calcium and switching the flow paths at every one day, it may be reduced to substantially one tenth compared with the case of non-switching. |
