The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 08, 2012
Filed:
Jun. 18, 2008
Kazushige Ishida, Hitachi, JP;
Yoichi Wada, Hitachinaka, JP;
Makoto Nagase, Mito, JP;
Masahiko Tachibana, Hitachi, JP;
Masao Endo, Kitaibaraki, JP;
Motomasa Fuse, Hitachinaka, JP;
Naoshi Usui, Tsuchiura, JP;
Motohiro Aizawa, Hitachi, JP;
Kazushige Ishida, Hitachi, JP;
Yoichi Wada, Hitachinaka, JP;
Makoto Nagase, Mito, JP;
Masahiko Tachibana, Hitachi, JP;
Masao Endo, Kitaibaraki, JP;
Motomasa Fuse, Hitachinaka, JP;
Naoshi Usui, Tsuchiura, JP;
Motohiro Aizawa, Hitachi, JP;
Hitachi-Ge Nuclear Energy, Ltd., Ibaraki, JP;
Abstract
The object of this invention is to provide a method for mitigating a stress corrosion cracking of reactor structural material which makes it possible to suppress the rise in the main steam line dose rate without secondary effects such as a rise in the concentration of radioactive cobalt-60, etc. in the reactor water. Hydrogen and a reductive nitrogen compound containing nitrogen having a negative oxidation number (for example, hydrazine) are injected into the core water of boiling water nuclear power plant. By injecting the reductive nitrogen compound containing nitrogen having a negative oxidation number into the core water, the stress corrosion cracking of structural material of reactor can be mitigated without side reactions such as a rise in the concentration of cobalt-60, etc.