Refine your search:     
Report No.
 - 
Search Results: Records 1-6 displayed on this page of 6
  • 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

Development of thermodynamic database for performance assessment of geological disposal of high-level radioactive waste and TRU waste

Kitamura, Akira

Nihon Genshiryoku Gakkai-Shi ATOMO$$Sigma$$, 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.

Journal Articles

Assessment of sorption and diffusion in the rock matrix in the NUMO safety case

Hamamoto, Takafumi*; Shibutani, Sanae*; Ishida, Keisuke*; Fujisaki, Kiyoshi*; Yamada, Motoyuki*; Tachi, Yukio

Proceedings of 6th East Asia Forum on Radwaste Management Conference (EAFORM 2017) (Internet), 6 Pages, 2017/12

NUMO has developed a generic safety case to demonstrate the feasibility and safety of geological disposal of HLW and TRU in Japan and to provide a basic structure for the safety case which will be applicable to any potential site. In this safety case, the safety assessment was carried out for the repositories tailored to site descriptive models developed for three representative rock groups (plutonic, Neogene sedimentary and Pre-Neogene sedimentary rocks). Radionuclide migration parameters in rocks, i.e. distribution coefficients (Kds) and effective diffusion coefficients (Des), were derived to allow safety analysis for a range of scenarios. In this generic stage, the values of these parameter were given as the statistical values derived from laboratory data for certain rock types. The data were extracted from the latest database, with interpretation based on radionuclide speciation derived from relevant groundwater thermodynamic modelings.

Journal Articles

Leaching behavior of simulated bituminized radioactive waste form under deep geological conditions

Nakayama, Shinichi; Iida, Yoshihisa; Nagano, Tetsushi; Akimoto, Toshiyuki

Journal of Nuclear Science and Technology, 40(4), p.227 - 237, 2003/04

 Times Cited Count:12 Percentile:61.24(Nuclear Science & Technology)

Leaching behavior of synthetic bituminized waste form was studied to inquire data for performance assessment of the geologic disposal. Laboratory-scale leaching tests were performed. The bituminized samples were contacted with an alkaline solution representing cement-contacting groundwater, with a saline solution simulating seawater for a possible repository construction at the coastal area, and with deionized water as reference. The release of soluble components, Na and Cs, was enhanced by the swelling, and considered to be diffusion controlled in the swelled layers of the specimens. The release of insoluble components such as Ba and Np was solubility-limited in addition to control by the progression of leaching. Neptunium, a redox-sensitive element, showed a distinct difference in release reflecting the difference between the anoxic and atmospheric conditions. The concentrations of Pu were below the detection limit ($$2 times 10^{-10}$$ mol/L) under all of the leaching conditions in this study.

JAEA Reports

Geochemical studies for geologic disposal of high-level radioactive waste; Research activities in Department of Environmental Safety Research, Japan Atomic Energy Research Institute

; Sato, Tsutomu; Nagano, Tetsushi; Yanase, Nobuyuki; Yamaguchi, Tetsuji; Isobe, Hiroshi; Onuki, Toshihiko; Sekine, Keiichi

JAERI-Review 95-011, 94 Pages, 1995/07

JAERI-Review-95-011.pdf:4.81MB

no abstracts in English

Oral presentation

Outline of research and development of spent fuel direct disposal in Japan

Hatanaka, Koichiro

no journal, , 

JAEA has initiated research and development of spent fuel direct disposal in FY 2013. In the research and development so far, we were able to construct approaches for design and safety assessment and to present the disposal concept based on multi barrier system as well as the technical level of the direct disposal, through carrying out the preliminary design and safety assessment, by taking characteristics of geological environment in Japan and the spent fuels into consideration. In addition, challenges/issues related to the design and safety assessment to be addressed towards the research and development in the next stage, were identified, classified and organized. In the future, we are going to present the technical reliability of the direct disposal by resolving the challenges/issues.

6 (Records 1-6 displayed on this page)
  • 1