PURPOSE: To make it possible for a user not only to exchange a treatment tank for the exchange of a treating medium but also to dispose of the treatment tank and the treating medium.

CONSTITUTION: A cup-shaped holder 4 which rotates on a slanted shaft is installed in an outer case 3. The bottom of the holder 4 is engaged with and inserted into a treatment tank 1 to hold it; a treating medium 2 is placed in the tank 1. A drying means 6 equipped with a suction fan 60 and a heater 61 is installed on the lid board 31 of the outer case 3 to face the inside of the tank 1. When the tank 1 is replaced for the exchange of the medium 2, air taken in by the suction fan 60 is heated by the heater 61 and sent into the tank 1 to dry the tank 1, the medium 2, and garbage A. The tank 1 is taken out through the opened lid board 31 to be disposed of by combustion with the medium 2 and the garbage A.