Refine your search:     
Report No.
 - 
Search Results: Records 1-9 displayed on this page of 9
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Experimental study on U-Pu cocrystallization reprocessing process

Shibata, Atsuhiro; Oyama, Koichi; Yano, Kimihiko; Nomura, Kazunori; Koyama, Tomozo; Nakamura, Kazuhito; Kikuchi, Toshiaki*; Homma, Shunji*

Journal of Nuclear Science and Technology, 46(2), p.204 - 209, 2009/02

 Times Cited Count:6 Percentile:43.89(Nuclear Science & Technology)

A new reprocessing system with 2-stage crystallization process has been developed. In the first stage of the system, U and Pu are recovered from dissolver solution by U-Pu co-crystallization. Laboratory scale experiments were carried out with U and Pu mixed solution and irradiated fuel dissolver solution to obtain fundamental data on U-Pu co-crystallization process. Pu co-crystallized with U, but crystallization yields of Pu were lower than those of U. FPs were separated from U and Pu by co-crystallization, and decontamination factors of Cs and Eu to U in crystal were over 100.

Journal Articles

Batch crystallization of uranyl nitrate

Chikazawa, Takahiro*; Kikuchi, Toshiaki*; Shibata, Atsuhiro; Koyama, Tomozo; Homma, Shunji*

Journal of Nuclear Science and Technology, 45(6), p.582 - 587, 2008/06

 Times Cited Count:17 Percentile:76.24(Nuclear Science & Technology)

Batch crystallization of uranyl nitrate is carried out in order to obtain fundamental data required for the development of reprocessing involving crystallization. Particular attention is paid to the development of a method for predicting the concentrations of uranium and nitric acid in the mother liquor and the amount of uranyl nitrate crystals produced. Initial concentrations of uranyl nitrate and nitric acid are 500-600 g/dm$$^{3}$$ and 4-6 mol/dm$$^{3}$$, respectively, corresponding to the condition of a dissolver solution of spent fuel. Steady-state mass balance equations including the correlation equation for the equilibrium solubility of uranium nitrate are applied to the prediction. The calculated concentrations of uranium and nitric acid are in close agreement with the experimental ones. The recovery of uranium is accurately predicted by the calculated concentrations, with an error of less than 5%.

Journal Articles

Flowsheet study of U-Pu Co-crystallization reprocessing system

Homma, Shunji*; Ishii, Junichi; Kikuchi, Toshiaki*; Chikazawa, Takahiro*; Shibata, Atsuhiro; Koyama, Tomozo; Koga, Jiro*; Matsumoto, Shiro*

Journal of Nuclear Science and Technology, 45(6), p.510 - 517, 2008/06

 Times Cited Count:11 Percentile:62.49(Nuclear Science & Technology)

U-Pu co-crystallization reprocessing system is proposed for LWR fuels and its flowsheet study is carried out. This reprocessing system is based on the experimental evidence indicating that hexavalent plutonium is co-crystallized with uranyl nitrate. The system consists of five steps: dissolution of spent fuel, Pu oxidation, U-Pu co-crystallization, dissolution of the crystals, and U crystallization. The system does not require organic solvent, expecting the enhancement of safety and cost-effectiveness. The system requires a recycling of the mother liquor from the U-Pu co-crystallization step to recover almost entire amount of U and Pu. The appropriate recycle ratio is determined for LWR fuels, such that the satisfactory decontamination is achieved. The mother liquor from the U re-crystallization step contains U and Pu. The flowsheet study shows that the constant ratio of Pu to U in the mother liquor can be controlled even though the composition of the spent fuel is different.

Journal Articles

Development of crystallizer for advanced aqueous reprocessing process

Washiya, Tadahiro; Kikuchi, Toshiaki*; Shibata, Atsuhiro; Chikazawa, Takahiro*; Homma, Shunji*

Proceedings of 14th International Conference on Nuclear Engineering (ICONE-14) (CD-ROM), 7 Pages, 2006/07

The crystallization is an advanced and remarkable technology in the future reprocessing process, which requires safety and cost advantages. Japan Atomic Energy Agency (JAEA), Mitsubishi Materials Corporation and Saitama University have been developing an annular-type continuous crystallizer. This paper mainly discussed about this crystallizer design and its development. JAEA has considered following two application processes of the crystallization technology. One is a uranium crystallization process, which applied before the solvent extraction process to recover excessive uranium from dissolver solution and reducing the throughput in the later extraction process. In this process, highly concentrated dissolver solution (about 500g-HM/L) is fed to this crystallizer, and only uranium is crystallized. Another is a plutonium co-crystallization process, which consists of two crystallization steps and excludes extraction process, and thus it's expected to reduce the waste generation and to improve operation safety. In this process, plutonium is co-crystallized with uranium in the first step and separated from residual solution, then the crystals are dissolved into nitric acid solution and excessive uranium is crystallized in the second step. This residual solution is recycled to fuel dissolution process, thus it contributes to reduce nitric acid quantity consumption. For both crystallization processes, same crystallizer design can be applied; we have developed a continuous crystallization system to establish high process throughput and optimizing of the crystallization processes. In the design study of the crystallizer, an annular-type was selected as the most promising design. The fundamental data was obtained by scale-down test device with uranium conditions, and an engineering scale crystallizer was fabricated to confirm the system performance in engineering scale.

JAEA Reports

None

Homma, Shunji*; Tajima, Yasunori*; Koga, Jiro*; Matsumoto, Shiro*

PNC TJ1609 97-001, 47 Pages, 1997/02

PNC-TJ1609-97-001.pdf:2.11MB

no abstracts in English

Oral presentation

Crystallization system development for advanced aqueous reprocessing process

Washiya, Tadahiro; Tayama, Toshimitsu; Nakamura, Kazuhito; Shibata, Atsuhiro; Yano, Kimihiko; Kamiya, Masayoshi; Komaki, Jun; Chikazawa, Takahiro*; Kikuchi, Toshiaki*; Homma, Shunji*; et al.

no journal, , 

no abstracts in English

Oral presentation

Study on U-Pu cocrystallization for reprocessing process

Shibata, Atsuhiro; Oyama, Koichi; Yano, Kimihiko; Nomura, Kazunori; Nakamura, Kazuhito; Koyama, Tomozo; Chikazawa, Takahiro*; Kikuchi, Toshiaki*; Ishii, Junichi; Homma, Shunji*; et al.

no journal, , 

no abstracts in English

Oral presentation

Nitrogen oxide closed system in the future reprocessing process, 6; Applicability to advanced aqueous reprocessing process

Takaoku, Yoshinobu*; Hattori, Isao*; Watanabe, Tetsuya*; Okaniwa, Takaaki*; Araya, Sadao*; Homma, Shunji*; Takano, Masato; Akai, Yoshie*; Suzuki, Yasuhiro*

no journal, , 

no abstracts in English

Oral presentation

Completion of the Handbook on Process and Chemistry of Nuclear Fuel Reprocessing, 3rd edition

Tsubata, Yasuhiro; Asakura, Toshihide; Tsutsui, Nao; Ban, Yasutoshi; Hotoku, Shinobu; Matsumura, Tatsuro; Morita, Yasuji; Homma, Shunji*

no journal, , 

The fundamental data on spent nuclear fuel reprocessing and related chemistry was collected and summarized as the 3rd edition of The "Handbook on Process and Chemistry of Nuclear Fuel Reprocessing". The purpose of this handbook is contribution to R&D on the spent fuel reprocessing and fuel cycle technology for high burnup uranium fuel and mixed oxide fuel utilization in near future, including minor actinides separation and recovery. Revised contents in this book was discussed and reviewed by specialists of science and technology on fuel reprocessing in Japan. In this poster presentation, the aim of the revised handbook and outline of revised data are introduced.

9 (Records 1-9 displayed on this page)
  • 1