Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 48

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

JAEA Reports

Critical mass evaluation of minor actinides in aqueous solution; Data for criticality safety assessment of separation process

Morita, Yasuji; Fukushima, Masahiro; Kashima, Takao*; Tsubata, Yasuhiro

JAEA-Data/Code 2020-013, 38 Pages, 2020/09

JAEA-Data-Code-2020-013.pdf:1.94MB

Critical Masses of Cm, Am and the mixture were calculated in metal-water mixtures with water reflector as a basic data for criticality safety assessment of minor actinide separation process. In the mixture of Cm-244 and Cm-245, higher ratio of Cm-245 gives smaller critical mass, but the amount of Cm-245 in the critical mass can be obtained by concentration of Cm-245 in the Cm mixture without depending on the Cm-245 ratio. Critical mass of Cm isotope mixture with 30% Cm-245 was smaller than that of Pu isotope mixture in the practical reprocessing (71% Pu-239 + 17% Pu-240 + 12% Pu-241). When Cm is separated from other element including Am and the solution is concentrated, measure for the critical accident has to be taken. Critical mass of Am-242m is smaller than that of Cm-245, but the ratio of Am-242m in the Am contained in practical spent fuel is small enough, about several percent, and therefore the critical accident by Am does not have to be considered. That by the mixture of Am and Cm does not either.

JAEA Reports

Collaboration between SCK$$cdot$$CEN and JAEA for Partitioning and Transmutation through Accelerator-Driven System

Working Group for Collaboration between SCK$$cdot$$CEN and JAEA for P&T through ADS

JAEA-Review 2017-003, 44 Pages, 2017/03

JAEA-Review-2017-003.pdf:5.35MB

This technical report reviews Research and Development (R&D) programs for the Partitioning and Transmutation (P&T) technology through Accelerator-Driven System (ADS) at Studiecentrum voor Kernenergie/Centre d'Etude de l'$'e$nergie Nucl$'e$aire (SCK$$cdot$$CEN) and Japan Atomic Energy Agency (JAEA). The results obtained in the present Collaboration Arrangement between the two organizations for the ADS are also summarized, and possible further collaborations and mutual realizations in the future are sketched.

Journal Articles

Highly practical and simple ligand for separation of Am(III) and Eu(III) from highly acidic media

Suzuki, Hideya; Tsubata, Yasuhiro; Kurosawa, Tatsuya; Shibata, Mitsunobu; Kawasaki, Tomohiro; Urabe, Shunichi*; Matsumura, Tatsuro

Analytical Sciences, 32(4), p.477 - 479, 2016/04

 Times Cited Count:18 Percentile:67.29(Chemistry, Analytical)

An impeccable, high-performance new reagent called alkyl diamide amine (ADAAM) was examined from the viewpoint of mutual separation of Am(III) and Eu(III). ADAAM has three donor atoms, one soft N-donor atom and two hard O-donor atoms, in the central frame. The combination of soft and hard atoms affords a tridentate donor set of atoms that ensures remarkable extractability and selectivity of Am(III) and Eu(III) in highly acidic media.

Journal Articles

A Study on accelerator-driven transmutation system in JAEA

Sasa, Toshinobu

AAPPS Bulletin, 24(5), p.13 - 17, 2014/10

To reduce the burden of radiological nuclides contained in spent nuclear fuel, Partitioning-Transmutation (P-T) technology is noted as an option for nuclear waste management in the new national strategic energy policy. As for the system for waste transmutation, an accelerator-driven system is desirable as a dedicated transmutor. To perform basic studies for an accelerator-driven system, the Japan Atomic Energy Agency has promoted the design of the Transmutation Experimental Facility within the framework of the J-PARC project. A lead-bismuth spallation target, which is bombarded with 400 MeV - 250 kW protons, and a low-power subcritical reactor will be installed in the facility. Construction will start within a few years after the national review of P-T technology.

Journal Articles

Present status and future perspective of research and development on partitioning and transmutation technology at JAERI

Oigawa, Hiroyuki; Minato, Kazuo; Kimura, Takaumi; Morita, Yasuji; Arai, Yasuo; Nakayama, Shinichi; Nishihara, Kenji

Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10

JAERI is engaging in the R&D on the Double-strata Fuel Cycle concept in accordance with the results of the check and review on the Partitioning and Transmutation (PT) technology made by the Atomic Energy Commission of Japan in 2000. As for the partitioning process, after the establishment of the "4-group Partitioning Process Concept", an innovative concept called ARTIST is also being studied. As for the fuel technology, minor actinide nitrides such as NpN and AmN were synthesized and their material properties have been measured. To reprocess the irradiated fuel, the pyrochemical process has been studied. The R&D of the accelerator-driven transmutation system are in progress for an accelerator, lead-bismuth, and a subcritical reactor. In addition, JAERI has started the high-intensity proton accelerator project (J-PARC), which includes the Transmutation Experimental Facility (TEF) as the Phase-II. The impact of PT technology on the backend of the nuclear energy utilization is also being discussed.

Journal Articles

Geologic disposal of radioactive waste produced by application of partitioning-transmutation technology to nuclear fuel cycle

Nakayama, Shinichi; Morita, Yasuji; Nishihara, Kenji; Oigawa, Hiroyuki

Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10

The effects of partitioning-transmutation (PT) technology to waste management was assessed based on the chemical and physical properties and estimated amounts of radioactively contaminated wastes that may be generated in the JAERI's PT cycle. The volume of high-level waste after partitioning was about a third that of non-partitioned vitrified waste form. The required repository area was about sixth, which implies increase in capacity of geologic repositories.

Journal Articles

Parametric survey on possible impact of partitioning and transmutation of high-level radioactive waste

Oigawa, Hiroyuki; Yokoo, Takeshi*; Nishihara, Kenji; Morita, Yasuji; Ikeda, Takao*; Takaki, Naoyuki*

Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10

The benefit of implementing Partitioning and Transmutation (P&T) of high-level wastes was parametrically surveyed. The possible reduction of the geological repository area was estimated. By recycling minor actinides (MA), the repository area required for unit spent fuel was reduced significantly in the case of MOX-LWR. This effect was caused by removal of $$^{241}$$Am which is a long-term heat source. By partitioning the fission products, in addition to MA recycling, further 70-80% reduction from the MA-recovery case can be expected for both UO$$_2$$ and MOX. This significant reduction was independent of the cooling time before the partitioning process.

JAEA Reports

Treatment and decomposition of HLW-79Y-4T type transportation cask for liquid radioactive fuel material

Yamaguchi, Isoo*; Morita, Yasuji; Fujiwara, Takeshi; Yamagishi, Isao

JAERI-Tech 2005-054, 61 Pages, 2005/09

JAERI-Tech-2005-054.pdf:12.38MB

The HLW-79Y-4T type transportation cask for liquid radioactive fuel material (commonly called "Cendrillon") was imported from France and modified for Japanese regulation in order to obtain high-level radioactive liquid waste (HLW) for partitioning tests in JAERI by transportation from Tokai Establishment of Japan Nuclear Fuel Cycle Development Institute. The cask was used for the HLW transportation five times from 1982 to 1990. After that, it was kept and maintained for next transportation of HLW from facilities outside JAERI. Finally, we decided to decompose the cask because HLW can be obtained in JAERI Tokai. For the decomposition, radiation dose and contamination by radioactivity was first measured and then the methods to reduce those levels were determined. The cask was decomposed after the decontamination to separate the part that has high radiation level. The separated part was put in a vessel specially prepared. The present report describes those procedures for the decomposition of the transportation cask.

JAEA Reports

Research and development on partitioning in JAERI; Review of the research activities until the development of 4-group partitioning process

Morita, Yasuji; Kubota, Masumitsu*

JAERI-Review 2005-041, 35 Pages, 2005/09

JAERI-Review-2005-041.pdf:2.24MB

Research and development on Partitioning in JAERI are reviewed in the present report from the beginning to the development of the 4-Group Partitioning Process and its test with real high-level liquid waste (HLLW). In the 3-Group Partitioning Process established in around 1980, elements in HLLW are separated into 3 groups of transuranium element group, Sr-Cs group and the other element group. The 4-Group Partitioning Process subsequently developed contains the separation of Tc-platinum group metals additionally. The process was tested to demonstrate its performance with real concentrated HLLW. Until then, various separation methods for various elements were studied and selection and optimization of the separation methods were carried out to establish the process. Review of the experience, findings and results is very important and valuable for future study on partitioning. The present report is prepared from this point of view.

Journal Articles

Accomplishment of 10-year research in NUCEF and future development; Process safety and development research

Morita, Yasuji; Asakura, Toshihide; Mineo, Hideaki; Hotoku, Shinobu; Uchiyama, Gunzo

JAERI-Conf 2005-007, p.25 - 30, 2005/08

Researches on process safety of reprocessing, development of an advanced reprocessing and partitioning of high-level liquid waste(HLLW) have been conducted in NUCEF - BECKY (Back-end Fuel Cycle Key Elements Research Facility), which has alpha-gamma concrete cells and many glove-boxes. This paper presents 10 year accomplishment of the above researches and future activities to be conducted in the field of separation process development.

JAEA Reports

Elemental separation simulation in the ARTIST process; Separation simulation of counter-current extractor by commercial software

Yamaguchi, Isoo*; Suzuki, Shinichi; Sasaki, Yuji; Yamagishi, Isao; Matsumura, Tatsuro; Kimura, Takaumi

JAERI-Tech 2005-037, 56 Pages, 2005/07

JAERI-Tech-2005-037.pdf:2.31MB

For the development of the reprocessing of spent nuclear fuels, the solvent extraction using the mixer-settler equipment is greatly available. This method has the advantages of the treatment of the large mass of materials and continuous operations. In case of the application of the mixer-settler devise, the precise calculation using the distribution ratio of metals in order to determine the metal concentration at each stage is indispensable. This calculation is performed in the development of ARTIST process. The metal concentration in each stage of ARTIST process is calculated by the simulation using excel software equipped with counter-current equations. This method is not taken into consideration of the change of acid concentration, therefore, we developed the new method to calculate the metal concentration even after acidity change. This method can calculate not only the metal concentration at each extraction step but also at each stage of mixer-settler. Using this calculation, we evaluated the optimum condition of solvent extraction in ARTIST process.

Journal Articles

Extraction studies of lanthanide(III) ions with ${it N,N'}$-dimethyl-${it N,N'}$-diphenylpyridine-2,6-dicarboxyamide(DMDPhPDA) from nitric acid solutions

Shimada, Asako; Yaita, Tsuyoshi; Narita, Hirokazu; Tachimori, Shoichi; Okuno, Kenji*

Solvent Extraction and Ion Exchange, 22(2), p.147 - 161, 2004/03

 Times Cited Count:60 Percentile:80.68(Chemistry, Multidisciplinary)

The distribution ratios of lanthanides with ${it N,N'}$-dimethyl-${it N,N'}$-diphenylpyridine-2,6-dicarboxyamide(DMDPhPDA) from 1-5M nitric acid solutions were determined and the extraction mechanism was discussed on the basis of the slope analyses of acid and ligand concentration dependencies and lanthanide patterns (variation of the distribution ratio as a function of ionic radius). The lanthanide extractions were explained through two mechanisms from the standpoint of the formation of the extracted complex as follows: (1) the formation of inner-sphere complex with two DMDPhPDA molecules for light lanthanides in the extraction from HNO$$_{3}$$ less than 3M, and (2) the formation of outer-sphere complex with the third DMDPhPDA molecules in addition to the inner-sphere complex in the extraction of light lanthanides from HNO$$_{3}$$ more than 3M, and those of heavy lanthanides from 1-5M HNO$$_{3}$$ solutions. Nitric acid concentration is more influential than the ligand concentration in the formation of outer-sphere complex.

Journal Articles

The Accelerator driven system strategy in Japan

Kurata, Yuji; Takizuka, Takakazu; Osugi, Toshitaka; Takano, Hideki

Journal of Nuclear Materials, 301(1), p.1 - 7, 2002/02

 Times Cited Count:11 Percentile:60.05(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

Back-extraction of uranium(VI) from organophosphoric acid with hydrazine carbonate

Watanabe, Masayuki; Tatsugae, Ryozo*; Shirahashi, Koichi; Morita, Yasuji; Kubota, Masumitsu*

Journal of Radioanalytical and Nuclear Chemistry, 250(2), p.377 - 379, 2001/11

 Times Cited Count:5 Percentile:40.34(Chemistry, Analytical)

no abstracts in English

JAEA Reports

ARTIST process; A Novel chemical process for treatment of spent nuclear fuel

Tachimori, Shoichi

JAERI-Research 2001-048, 23 Pages, 2001/10

JAERI-Research-2001-048.pdf:1.88MB

A new chemical process, ARTIST process, is proposed for the treatment of spent nuclear fuel. The main concept of the ARTIST process is to recover and stock all actinides (Ans) in two groups, uranium (U) and a mixture of transuranics (TRU), to preserve their resource value and to dispose solely fission products (FPs). The process composed of two main steps, an U exclusive isolation and a total recovery of TRU; which copes with the nuclear non-proliferation measures, and additionally Pu separation process and soft N-donor process if requested, and optionally processes for separation of long-lived FPs. These An products: U-product and TRU-product, are to be solidified by calcination and allowed to the interim stockpile for future utilization. These separations are achieved by use of amidic extractants in accord with the CHON principle. The technical feasibility of the ARTIST process was explained by the performance of both the branched-alkyl monoamides the diglycolic amide (TODGA) in thorough extraction of all TRU by tridentate fashon.

JAEA Reports

Separation and immobilization of Sr and Cs contained in acidic media by using inorganic ion-exchangers (literature survey)

Yamagishi, Isao

JAERI-Review 2001-027, 52 Pages, 2001/07

JAERI-Review-2001-027.pdf:3.59MB

The present study deals with the survey of inorganic ion-exchangers suitable for separation and immobilization of Sr and Cs contained in acidic high-level liquid waste. For separation and immobilization of Cs, crystalline silicotitanate seems to be the most promising exchanger. For selective separation of Sr, there is no promising exchanger up to now. Sintered ceramics are favorable waste forms of inorganic ion-exchangers. Their stabilities are largely influenced by composition of exchangers, qualities of ceramics and disposal scenario.

JAEA Reports

A Review on studies of the transport and the form of radionuclides in the fluvial environment

Matsunaga, Takeshi

JAERI-Review 2001-018, 121 Pages, 2001/06

JAERI-Review-2001-018.pdf:5.95MB

The present report reviews a series of studies conducted in JAERI which have dealt with the behavior of atmospherically-derived radionuclides in a fluvial environment. The studies cited here firstly include investigations of the evaluation of the transport rate of the atmospherically-derived 137Cs, 210Pb and 7Be from the ground via a river to the downstream areas where the affected water is consumed. The studies validated i) the importance of suspended particulate materials in the fluvial discharge of those radionuclides, and ii) a methodology to estimate the discharge of those radionuclides. Secondly, studies in rivers and lakes in the vicinity of the Chernobyl Nuclear Power Plant revealed the role of natural dissolved organics in affecting the dissolution and transport of 239,240Pu, 241Am through complexation to form soluble species with the aid of a chemical equilibrium model The same sort of a model was also applied successfully for the behavior of iron and manganese (hydr)oxides in river recharged aquifers which could bear riverborne radionuclides.

Journal Articles

Targets for LIFP transmutation

Minato, Kazuo

Nihon Genshiryoku Gakkai 'Kodo Nenryo Gijutsu' Kenkyu Senmon Iinkai Hokokusho, No.115, p.481 - 486, 2001/06

no abstracts in English

Journal Articles

System design of a superconducting linac for the JAERI-KEK joint project

Hasegawa, Kazuo; Mizumoto, Motoharu; Ouchi, Nobuo; Noguchi, Shuichi*

KEK Proceedings 99-25, p.28 - 32, 2000/02

no abstracts in English

Journal Articles

Management of minor long-lived nuclides in nuclear fuel reprocessing

Uchiyama, Gunzo; Mineo, Hideaki; Asakura, Toshihide; Hotoku, Shinobu; Kamei, Kazushige; Watanabe, Makio; Fujine, Sachio

Proceedings of 12th Pacific Basin Nuclear Conference (PBNC 2000), Vol.1, p.531 - 538, 2000/00

no abstracts in English

48 (Records 1-20 displayed on this page)