Evaluation of Effectiveness of Hydrogen Water Chemistry for Different Types of Boiling Water Reactors

Abstract

Short period tests of hydrogen water chemistry (H\VC) were carried out at Tsuruga-1 and Tokai-2 Nuclear Power Plants. The effects of H\VC at Tsuruga-1, a non-jet pump plant, are larger than those at Tokai-2, a jet pump plant; this is caused by the much higher recombination rate of hydrogen and oxygen at the downcomer region under suitable gamma ray irradiation for the former. The effective oxygen concentrations ([02]err=[02]+1/2[H202]) in water measured at the reactor pressure vessel bottom are suppressed by HWC as effectively as those concentrations at the recirculating lines in both plants.The effects of HWC in both plants were analyzed and compared with literature data on H\VC to evaluate the differences in the effectiveness of H\VC as caused by reactor type. From the evaluation, it was concluded that the effectiveness of H\VC is much more affected by the power density in the core and the average dose rate at the downcomer than by the reactor type itself. The authors propose an evaluation concept for HWC effectiveness. This is the recombination factor, which is defined as a function of dose rate factor at the downcomer.

Effects of Hydrogen Peroxide on Corrosion of Stainless Steel, (III) Evaluation of Electric Resistance of Oxide Film by Equivalent Circuit Analysis for Frequency Dependent Complex Impedances

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Development of a method to lower recontamination after chemical decontamination by depositing Pt nano particles: (I) Consideration of the suppression mechanism using a quantum dynamics calculation

“…Intergranular stress corrosion cracking (IGSCC) is one of the serious problems encountered with structural materials in BWRs [4][5][6]. During the 1980s and early 1990s, the combined technology of hydrogen injection to the feedwater and noble metal chemical addition (NMCA) was applied to BWRs in the United States to mitigate the IGSCC [7][8][9].…”

Water chemistry technology – one of the key technologies for safe and reliable nuclear power plant operation

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