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Nakamura, Hirofumi; Nagai, Toshihisa; Suto, Toshiyuki; Kosaka, Ichiro; Nakazaki, Katsutoshi; Suto, Shinya; Nakamura, Tomotaka; Nakabayashi, Hiroki; Hayashi, Naoto; Sumida, Daisaku
JAEA-Technology 2008-077, 276 Pages, 2008/12
JAEA-Technology-2008-077.pdf:25.66MB
Japan Atomic Energy Agency (JAEA) has been conducting "Fast Reactor Cycle Technology Development Project (FaCT Project)" for the purposes of researching and developing the technologies for the fast breeder reactor cycle commercialization since Japanese fiscal year (JFY) 2007. Based on the above R&D program for reprocessing system, the engineering-scale hot test would provide demonstration data on the specification, operation and maintenance of the adapted innovative technologies, system and plant. And more, these results would be fed to the design of the demonstration facility planning on the FaCT project road map. This report is the interim report of design studies about the engineering-scale hot test facility and includes not only design of the equipment and facility, but also consideration for design principle, requirements and facility basic planning.
Nakabayashi, Hiroki; Nagai, Toshihisa
Proceedings of 2008 International Congress on Advances in Nuclear Power Plants (ICAPP '08) (CD-ROM), p.2029 - 2035, 2008/06
We performed a basic design of the solvent extraction test system with centrifugal contactors for the engineering-scale hot examination facility to ensure the development and commercialization of the advanced aqueous reprocessing technology for fast reactor fuels in Japan. The system was designed to have the ability to operate two different flowsheet, the simplified solvent extraction method and the co-processing method, which we proposed as promising solvent extraction processes. In the design, various engineering issues, such as error of flow rate of reagent pumps and a dissolver solution feeder, error of chemical analyses and environmental temperature fluctuation, were delt with. For the design we modified and used the computer code "MIXSET-X" which was developed to simulate solvent extraction system by JAEA in 1999. The validity of the modified code was benchmarked by comparison with an engineering scale uranium test.
Ojima, Hisao; Hayashi, Naoto; Nagai, Toshihisa; Fujita, Yuji; Kawata, Tomio
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 5 Pages, 2005/10
This paper mentions a preliminary evaluation on the typical LWR-to-FBR transition scenarios. Deployment rate of FBRs is strongly connected with replacement rate of LWRs, however, the transition should be seen as a matter of the optimization of fuel cycle systems. Based on the Pu balance evaluation, it seems definitely necessary to save an adequate amount of LWR spent fuels before beginning the deployment of FBRs. The mission of the second LWR fuel reprocessing plant in Japan will most provably be to feed Pu needed for starting up new FBRs. Along with the Pu utilization, especially as LWR-MOX fuel, the accumulation of minor actinides(MAs) in the high-level radioactive waste will become dominant and finally result in larger number of vitrified HLW because of heat generation from MAs. MA recovery cycle combined with the FBR will gives successful solution on this matter. Requirements on the next generation reprocessing plant, which corresponds to the transition scenario, are studied and innovative concept named
Nakamura, Hirofumi; Abe, Tomiyuki; Kashimura, Takao; Nagai, Toshihisa; Maeda, Seiichiro; Yamaguchi, T.; Kuroki, Ryoichiro
JNC TN8440 2003-016, 39 Pages, 2003/07
JNC-TN8440-2003-016.pdf:0.79MB
The Generation-II Project Task Force Team has investigated a research and development plan on a future nuclear fuel cycle in Tokai works for about three months from December 19,2002. First we have discussed about the present condition of Japanese nuclear fuel cycle and have recognized it as the following. *The relation of the technology between the LWR-cycle and the FBR-cycle is not clear. *MOX Fuel Use in Light Water Reactors is important to establish technology of the FBR fuel cycle. *Radioactive waste disposal issue is urgent. Next we have proposed the three basic policies on R&D plan of nuclear fuel cycle in consideration of the F.S. on FBR-cycle. *Establishment and advancement of "the tough nuclear fuel cycle". *Early establishment of the FBR cycle technology to be able to supply energy stably for long-term. *Establishment of the radioactive waste treatment and disposal technology, and optimization of nuclear fuel cycle technology from the viewpoint of radioactive waste.And we have proposed the Japanese technical holder system to integrate all LWR and FBR cycle technology.
Nagai, Toshihisa; Ojima, Hisao; ;
Proceedings of 10th International Conference on Nuclear Engineering (ICONE-10), 0 Pages, 2002/00
None
Yamanouchi, Takamichi; Kyue, Tadashi; Nagai, Toshihisa
PNC TN8410 97-368, 135 Pages, 1997/12
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Nagai, Toshihisa; Nomura, Shigeo; Ojima, Hisao
Nihon Genshiryoku Gakkai Homu Peji (Internet), ,
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Nakamura, Hirofumi; Nagai, Toshihisa; Suto, Shinya; Shimada, Takashi; Funasaka, Hideyuki; Sugiyama, Toshihide
no journal, ,
no abstracts in English
Asakura, Toshihide; Tsubata, Yasuhiro; Morita, Yasuji; Nakabayashi, Hiroki; Nagai, Toshihisa
no journal, ,
To contribute to optimize the simple solvent extraction process of NEXT process, PARC-L code simulation calculations of U-Pu-Np co-extraction process were performed, and the extraction/separation behaviors of Np were examined from the viewpoint of oxidation/reduction reaction rate of Np (V)-Np (VI) in relating to the nitrous acid concentration. The time-dependent change of Np valence state distribution in the feed solution was calculated. Assuming the composition of the feed solution as that obtained from the valence calculation, extraction calculations were performed.
Maekawa, Keisuke; Nagai, Toshihisa; Ono, Kiyoshi
no journal, ,
Japan Atomic Energy Agency (JAEA) has developed a future vision titled "JAEA 2050 +", which outlines its ideal image for the future, namely the goal we should seek and the actions we should take toward this goal in order to continue our social contribution into the future. "JAEA 2050 +" was released to the public on October 31, 2019. This presentation shows outline of activities aimed to contribute to alleviating the risk of global climate change with nuclear science and technology, to energy security using nuclear energy systems with enhanced safety, including the nuclear fuel cycle and to the realization of future society (Society 5.0) through nuclear science and technology.