DISTILLATION DEVICE

PURPOSE:To produce high-purity water with the distillation device of making distilled water from the raw water subjected to an ion exchange treatment or reverse osmosis membrane treatment by passing the vapor generated in the device through a hydrophobic porous membrane. CONSTITUTION:The raw water 1 treated by the reverse osmosis membrane or the ion exchange resin is preheated by a heat exchanger 3 and is then admitted into a heat exchanger 4 where the raw water is reheated. The reheated water 1 enters a deaeration tank 5 and is heated by a heater 8 to generate the vapor 6. The hot water 9 from which the dissolved gas and TOC in the water are removed enters a still 10 and comes into contact with a heat transfer surface 11 in the state of thin film evaporation. The vapor generated in the still 10 is heated to a high temp. and high pressure by a heater 12 and is passed through a permeable evaporating film 13. The fine particles and water mists are removed therein and after the passage through the film 13, the vapor comes into contact with the heat transfer surface 11 and is thereby condensed. Since the intrusion of impurities into the water is suppressed, the high-purity distilled water is obtd.