To easily control the concentration of dissolved nitrogen to be necessary in a use point without wasting added nitrogen while removing dissolved oxygen in ultrapure water that is treated water.
The pure water production apparatus comprises: a primary pure water tank 11 for storing the treated water that contains dissolved oxygen; an ultraviolet oxidation apparatus 14 that irradiates the treated water from the primary pure water tank 11 with ultraviolet; a non-regeneration type mixed bed ion-exchange apparatus 21 that removes an ion component in the treated water having irradiated with the ultraviolet; a supply line that supplies the treated water from which ion has been removed to the use point; and a circulation line that branches from the supply line and returns a portion or all of treated water to the primary pure water tank 11. The apparatus is further provided with: a nitrogen addition apparatus 15 that adds nitrogen to the treated water; and a dissolved oxygen removing apparatus 17 that is provided with a catalytic metal carrier supporting a platinum group metal, and brings the treated water to which the nitrogen has been added into contact with to the catalytic metal carrier to remove the dissolved oxygen in the treated water.
SUGAWARA HIROSHI
| JPH10309566A | 1998-11-24 | |||
| JP2007000699A | 2007-01-11 | |||
| JPH05269306A | 1993-10-19 | |||
| JP2005270793A | 2005-10-06 | |||
| JP2008086879A | 2008-04-17 | |||
| JP2002307080A | 2002-10-22 |
Ishibashi Masayuki
Masaaki Ogata
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