PROBLEM TO BE SOLVED: To reduce a number of electrically-driven proportional valves to be used for reducing cost.SOLUTION: A treatment tank 3 stores an object 2 to be treated and water. Circulation means 9 makes stored water in the treatment tank 3 between a heat exchanger 8. On a circulation path 14, a bypass path 15 connecting front and rear parts of the heat exchanger 8, is provided. A distribution ratio of the water from the treatment tank 3 to be returned to the treatment tank 3 via the heat exchanger 8 and the water to be returned to the treatment tank 3 via the bypass path 15, can be adjusted by a cross valve 27. Steam supply means 10 supplies steam to the heat exchanger 8 for heating the circulation water by circulated the circulation means 9. Cooling means 11 supplies cooling water to the heat exchanger 8 for cooling the water circulated by the circulation means 9. The steam supply means 10 has a steam supply valve 29 for switching presence/absence of steam supply to a steam supply path 28 toward the heat exchanger, by on-off. In a sterilization step, in a state that the steam supply valve 29 is opened, the cross valve 27 is controlled based on temperature in the treatment tank 3.COPYRIGHT: (C)2015,JPO&INPIT【課題】使用する電動比例弁の数を削減して、コスト削減を図る。【解決手段】処理槽3には、被処理物2が収容されると共に水が貯留される。循環手段9は、処理槽3内の貯留水を熱交換器8との間で循環させる。循環路14には、熱交換器8の前後を接続してバイパス路15が設けられる。処理槽3からの水を、熱交換器8を介して処理槽3へ戻すか、バイパス路15を介して処理槽3へ戻すかの分配割合を、三方弁27で調整可能である。給蒸手段10は、循環手段9による循環水を加熱するために、熱交換器8に蒸気を供給する。冷却手段11は、循環手段9による循環水を冷却するために、熱交換器8に冷却水を供給する。給蒸手段10は、熱交換器8への給蒸路28に、給蒸の有無をオンオフで切り替える給蒸弁29を備える。殺菌工程では、給蒸弁29を開いた状態で、処理槽3内の温度に基づき三方弁27を制御する。【選択図】図1
