Hitachi-ge Nuclear Energy, Ltd.

Hitachi, Ltd.

Hitachi Service Eng., Co. Ltd.

Satoshi Oouchi

Koji Tanaka

Takashi Watanabe

Makoto Nagase

Kazushige Ishida

Hideyuki Hosokawa

Nobuyuki Ota

Ryo Hamada

Takashi Oohira

Motohiro Aizawa

Yoshio Takikawa

Masao Ohi

Naobumi Tsubokawa

Yasuto Kondoh

Masahiko Kazama

Hiroo Yoshikawa

Shintaro Yanagisawa

Mizuho Tsuyuki

Toru Kawasaki

Shintarou Yanagisawa

Provided are a chemical decontamination method and a chemical decontamination apparatus capable of preventing deterioration of a metal ion exchange resin and performing decontamination at a low cost in a short time. The chemical decontamination method of the invention includes: a reduction decontamination step of supplying a reduction decontamination solution to a decontamination target portion and performing reduction decontamination on a surface of a member constituting the decontamination target portion; a hydrogen peroxide decomposition step of decomposing hydrogen peroxide contained in the reduction decontamination solution after the reduction decontamination step; and a metal ion removing step of removing a metal ion contained in the reduction decontamination solution after the hydrogen peroxide decomposition step.

Chemical decontamination method and chemical decontamination apparatus

A chemical decontamination method capable of improving the decontamination efficiency of chemical decontamination of a steam dryer in the RPV is provided. In particular, the decontamination method includes feeding a chemical decontamination aqueous solution into a reactor pressure vessel in which a steam dryer is arranged, and after chemical decontamination of the steam dryer, the water level of the chemical decontamination aqueous solution existing in the reactor pressure vessel is lowered to a first water level below the lower end of the steam dryer.

Chemical decontamination method

A current-collecting brush apparatus is disclosed in which brushes are held slidably on a brush holder and pressed against a rotor by a brush-pressing spring. Pigtails connected to supply current to the brushes comprise a plurality of spiral conductors in parallel which are connected by being coiled in mutual opposite directions to offset the magnetic fluxes generated therein.

Current-collecting brush apparatus

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Hitachi, Japan

Satoshi Oouchi