| 摘要 |
PROBLEM TO BE SOLVED: To provide a vacuum dryer which is simple in structure and is high in drying speed of waste.SOLUTION: A vacuum dryer M1 includes an oil type vacuum pump 2 for vacuating a drying tank 1 which is provided with a dry room 11 housing a dried object D and the dry room 1. The drying tank 1 and the oil type vacuum pump 2 are connected by circulating pipes 4, 5, and the circulating pipes 4, 5 are provided with a cold trap 3 for condensing steam. To the drying tank 1 and the cold trap 3, heat pumps 6 are connected, respectively. Moisture of the dried object D evaporating in the dry room 11 becomes steam and is carried to the cold traps 3, where the steam is condensed into water. The heat pump 6 transfers condensation heat in the cold trap 3 to the drying tank 1 and uses it as evaporation heat. A temperature of an evaporation side heat medium supplied for the drying tank by the heat pump 6 is 70°C or higher. |
