| 摘要 |
PROBLEM TO BE SOLVED: To decrease the running cost necessary when exhaust gas is plasma- treated continuously by removing impurities coexisting with an inert gas such as helium in the exhaust gas to be discharged into a chamber, recovering the inert gas and circulating/reusing the recovered inert gas. SOLUTION: An impurity removing unit 26 for removing impurities such as steam and oxygen coexisting with the inert gas such as helium in the exhaust gas is arranged in an exhaust gas discharging route 22 from the chamber 21 where an atmospheric pressure plasma treating device 20 is installed. The inert gas in which the impurities are removed by the unit 26 is recovered and stored in a tank 29. The recovered inert gas is circulated and reused by returning to a supply route 35 of a fresh inert gas or a mixed reactive gas to the device 20. |
