Category Archives: Study on Neutron Spectrum of Pulsed Neutron Reactor

Method Development for Calculating Minor Actinide Transmutation in a Fast Reactor

Toshikazu Takeda, Koji Fujimura, and Ryota Yamada Abstract To effectively transmute minor actinides (MAs), which have long-lived radioactivity and high decay heat, fast reactors are very promising because many minor actinides can be loaded and transmutation rates are high compared to light water reactors. With the increase of loaded minor actinides, the neutron spectrum becomes hard and core safety parameters […]

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Transmutation Scenarios after Closing Nuclear Power Plants

Kenji Nishihara, Kazufumi Tsujimoto, and Hiroyuki Oigawa Abstract With consideration of the phase-out option from nuclear power (NP) utilization in Japan, an accelerator-driven system (ADS) for Pu transmutation has been designed and scenario analysis performed. The ADS is designed based on the existing ADS design for MA transmutation, and the six-batch ADS was selected as a reference design for scenario […]

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Concluding Summary

For the decommissioning of the Fukushima Daiichi Nuclear Power Station Units 1, 2, and 3, research and development activities have been pursued to retrieve fuel debris from the pressure and containment vessels of each reactor unit. In prepara­tion for the retrieval, however, there remain serious problems concerning the cooling water of fuel debris from the aspect of criticality safety.

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Development of a Rapid Analytical Method for 129I in the Contaminated Water and Tree Samples at the Fukushima Daiichi Nuclear Power Station

Asako Shimada, Mayumi Ozawa, Yutaka Kameo, Takuyo Yasumatsu, Koji Nebashi, Takuya Niiyama, Shuhei Seki, Masatoshi Kajio, and Kuniaki Takahashi Abstract The separation conditions for iodine species were investigated to analyze 129I in contaminated water and tree samples generated from the Fukushima Daiichi Nuclear Power Station (FDNPS). Inorganic iodine species in the samples from FDNPS were thought to be iodide (I_) […]

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HLW Disposal Program in Japan

Japan’s research and development program for HLW disposal started in 1976 (Fig. 24.1). The first progress report was released in 1992 by PNC (Power Reactor and Nuclear Fuel Development Corporation). PNC was reorganized as JNC (Japan Nuclear Fuel Cycle Development Institute) in 1998, then merged with JAERI (Japan Atomic Energy Research Institute) to be JAEA (Japan Atomic Energy Agency) in […]

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Background and Objectives

The estimated sustainable life period of the existing final disposal sites for munic­ipal solid wastes (MSW) in Japan was only 18 years as of the end of FY2008. Therefore, waste avoidance, waste volume reduction, and recycling of MSW have been a national policy. However, the Fukushima Daiichi Nuclear Power Plant (F1) accident has created an entirely new dimension in environmental […]

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