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Kitamura, Akira
JAEA-Data/Code 2020-020, 164 Pages, 2021/03
Part of JAEA's Thermodynamic Database (JAEA-TDB) for solubility and speciation of radionuclides (JAEA-TDB-RN) for performance assessment of geological disposal of high-level radioactive and TRU wastes has been updated with subsuming the database for geochemical calculations (JAEA-TDB-GC). This report has focused to update JAEA-TDB-RN after selecting change in standard Gibbs free energy of formation (), change in standard enthalpy change of formation (
), standard molar entropy (
) and, heat capacity (
), change in standard Gibbs free energy of reaction (
), change in standard enthalpy change of reaction (
) and standard entropy change of reaction (
) as well as logarithm of equilibrium constant (log
) at standard state. The extent of selection of these thermodynamic data enables to evaluate solubility and speciation of radionuclides at temperatures other than 298.15 K. Furthermore, the latest thermodynamic data for iron which have been critically reviewed, selected and compiled by the Nuclear Energy Agency within Organisation for Economic Co-operation and Development (OECD/NEA) have been accepted. Most of previously selected log
have been refined to confirm internal consistency with JAEA-TDB-GC. Text files of the updated JAEA-TDB have been provided for geochemical calculation programs of PHREEQC and Geochemist's Workbench.
Kitamura, Akira; Yoshida, Yasushi*
Journal of Radioanalytical and Nuclear Chemistry, 327(2), p.839 - 845, 2021/02
Times Cited Count:3 Percentile:34.89(Chemistry, Analytical)Thermodynamic data for radium for radioactive waste management have been predicted using an electrostatic model and correlation with the ionic radii of the alkaline earth metals. Estimation of the standard Gibbs free energy of formation and standard molar entropy of aqueous radium species and compounds has been based on such approaches as extrapolation of the thermodynamic properties of strontium and barium, and use of a model of ion pair formation. The predicted thermodynamic data for radium have been compared with previously reported values.
Kitamura, Akira; Yoshida, Yasushi*; Goto, Takahiro*; Shibutani, Sanae*
Genshiryoku Bakkuendo Kenkyu (CD-ROM), 27(2), p.58 - 71, 2020/12
Evaluation and estimation of solubility values are required for a performance assessment of geological disposal of high-level radioactive and TRU wastes. Selection of solubility-limiting solid phases (SSPs) that control the solubility of radionuclides is necessary for the evaluation and estimation of solubility values. The authors have developed a methodology for selection of the SSP through a calculation of saturation indices (SIs) using thermodynamic database to show a transparent procedure for the selection. Literature survey should be performed to confirm decision of the SSP from candidate SSPs which generally have larger SIs from realistic point of view for precipitation and solubility control. The authors have selected the SSPs for the elements of interest for the latest Japanese performance assessment in bentonite and cement porewaters after grouping various water compositions.
Kitamura, Akira
Nihon Genshiryoku Gakkai-Shi ATOMO, 62(1), p.23 - 28, 2020/01
Thermodynamic databases (TDBs) for performance assessment of geological disposal of high-level waste and TRU waste have been developed to predict solubility and speciation of radionuclides in groundwater in some countries including Japan. The present manuscript briefly describes current status of development of the TDB organized by the Nuclear Energy Agency within the Organisation of Economic Co-operation and Development (OECD/NEA) and the TDBs in some countries including Japan.
Kitamura, Akira
JAEA-Data/Code 2018-018, 103 Pages, 2019/03
The latest available thermodynamic data were critically reviewed and the selected values were included into the JAEA-TDB for performance assessment of geological disposal of high-level radioactive and TRU wastes. This critical review specifically addressed thermodynamic data for (1) a zirconium-hydroxide system through comparison of thermodynamic data selected by the Nuclear Energy Agency within the Organisation for Economic Co-operation and Development (OECD/NEA), (2) complexation of metal ions with isosaccharinic acid based on the latest review papers. Furthermore, the author performed (3) tentative selection of thermodynamic data on ternary complexes among alkaline-earth metal, uranyl and carbonate ions, and (4) integration with the latest version of JAEA's thermodynamic database for geochemical calculations. The internal consistency of the selected data was checked by the author. Text files of the updated and integrated thermodynamic database have been prepared for geochemical calculation programs of PHREEQC and Geochemist's Workbench.
Yamane, Yuichi; Amano, Yuki; Tashiro, Shinsuke; Abe, Hitoshi; Uchiyama, Gunzo; Yoshida, Kazuo; Ishikawa, Jun
Journal of Nuclear Science and Technology, 53(6), p.783 - 789, 2016/06
Times Cited Count:6 Percentile:46.39(Nuclear Science & Technology)The release behavior of radioactive materials from high active liquid waste (HALW) has been experimentally investigated under boiling accident conditions. In the experiments using HALW obtained through laboratory scale reprocessing, release ratio was measured for the FP nuclides such as Ru, Tc, Cs, Sr, Nd, Y, Mo, Rh and actinides such as
Cm,
Am. As a result, the release ratio was 0.20 for Ru and 1
for the FP and Ac nuclides. Ru was released into the gas phase in the form of both mist and gas. For its released amount, weak dependency was found to the initial concentration in the test solution. The release ratio decreased with the initial concentration. For other FP nuclides and actinides as non-volatile, released into the gas phase in the form of mist, the released amount increased with the initial concentration. The release ratio of Ru and NOx concentration increased with temperature of the test solutions. They were released almost at the same temperature between 200 and 300
C. Size distribution of the mist and other particle was measured.
Mitsuda, Motoyuki; Sasaki, Toshiki
JAEA-Technology 2015-013, 29 Pages, 2015/06
For implementation of disposal of the radioactive waste generated from Japan Atomic Energy Agency, Waste Management System which manages all of the waste data has been developed. We surveyed the kinds of data needed for the waste management at each site, and we set the standard waste management data items. We developed conceptual design for the waste management system and established the system for major sites, Nuclear Science Research Institute, Ningyo-toge Environmental Engineering Center, Fugen Decommissioning Engineering Center, Oarai Research and Development Center, Nuclear Fuel Cycle Engineering Laboratories. For other small sites, we accumulate waste data to the common waste storage database. Therefore, we have developed the system which manages the quality assurance waste data depending on waste treatment situation in JAEA.
Oshima, Soichiro; Shiraishi, Kunio; Shimada, Taro; Sukegawa, Takenori; Yanagihara, Satoshi
JAERI-Tech 2005-046, 46 Pages, 2005/09
A model for estimating decommissioning costs consisting of labor cost, device cost and expense, was developed for items which OECD/NEA had standardized, and was installed into the computer system for planning and management of reactor decommissioning (COSMARD). Input data files and databases for the decommissioning of JPDR were prepared, and the decommissioning cost was calculated with COSMARD. In addition, the decommissioning cost for a large scale BWR power plant was also calculated on the assumption of the advantage of scale. The calculations have shown that it is useful and efficient for studying the decommissioning costs for nuclear reactors to apply the COSMARD with database for cost estimation to the decommissioning cost calculation.
Oshima, Soichiro; Sukegawa, Takenori; Shiraishi, Kunio; Yanagihara, Satoshi
JAERI-Tech 2001-086, 83 Pages, 2001/12
Project management data on dismantling the Japan Power Demonstration Reactor (JPDR) was calculated using the Code System for Planning and Management of Reactor Decommissioning (COSMARD), and then its validity was studied by comparing the calculation results with actual data. In addition, work breakdown structure models and database were modified to meet an evaluation with changing work difficulty of preparation and cleanup activities, and calculations were further conducted to analyze feasibility by changing various conditions on cutting and conditioning activities. As the results, COSMARD was verified to be useful by confirming calculation capability on reflection of actual work conditions and relatively good agreement between actual data and calculations. Moreover, it was cleared that main parameters such as work difficulty of preparation and cleanup activities and the cutting speed in demolition work could affect to manpower within 30% in each calculations.
Department of Fuel Cycle Safety Research
JAERI-Review 2001-019, 108 Pages, 2001/07
Department of Fuel Cycle Safety Research, JAERI, has been carrying out research on safe and rational disposal systems of radioactive wastes arising from medical activities and research institutes (RI and Research Institute Waste). The research area includes a study on molten solidified waste form, a geological survey on Japan, a proposal on integrated disposal systems, data acquisition for safety evaluation, and a safety analysis of disposal systems. This report introduces progress and future works for the treatment and disposal of RI and Research Institute Waste.
Shiraishi, Kunio; Sukegawa, Takenori; Yanagihara, Satoshi
JAERI-Data/Code 99-050, p.113 - 0, 2000/01
no abstracts in English
; Sukegawa, Takenori; Yanagihara, Satoshi
JAERI-Data/Code 98-010, 186 Pages, 1998/03
no abstracts in English
Fukahori, Tokio; Katakura, Junichi
Nihon Genshiryoku Gakkai-Shi, 40(5), p.363 - 366, 1998/00
Times Cited Count:0 Percentile:0.00(Nuclear Science & Technology)no abstracts in English
Takeda, Seiji; ; Kimura, Hideo; Matsuzuru, Hideo
JAERI-Research 95-069, 47 Pages, 1995/11
no abstracts in English
Sukegawa, Takenori; ; ; Yanagihara, Satoshi
The 3rd JSME/ASME Joint Int. Conf. on Nuclear Engineering (ICONE),Vol. 4, 0, p.1779 - 1784, 1995/00
no abstracts in English
Yanagihara, Satoshi; Tachibana, Mitsuo; ;
Proc., The 1994 Int. Symp. on Decontamination & Decommissioning, 0, 6 Pages, 1994/00
no abstracts in English
Nitta, Ayako; Oki, Keiichi; Koma, Yoshikazu
no journal, ,
Various radioactive wastes generated in Fukushima Daiichi Nuclear Power Station should be safely disposed of. The properties of the wastes are required to understand. For that, the wastes are sampled and performed analyses. To utilize obtained analytical data, the database "FRAnDLi" was made to provide the data through the Internet.
Kobayashi, Taishi*; Sasaki, Takayuki*; Kitamura, Akira
no journal, ,
The solubility of U(OH)(am) was investigated in the presence of isosaccharinic acid (ISA) as a function of hydrogen ion concentration (pHc) and ISA concentration. The solubility in neutral pH region was independent of pHc, while those in alkaline pH region slightly increased with increasing pHc. The solubility was investigated as a function of ISA concentration and found to increase with a slope of approximately 2 with increasing ISA concentration. It was therefore suggested that U(OH)
(ISA)
and U(OH)
(ISA)
were the dominant U(IV)-ISA complexes, which were similar to those observed in Zr(IV)-ISA system. Complex formation constants were determined by the least square fitting analysis of the solubility data and the calculated solubility curve well reproduced the experimental data.