JOPSS - Search Results

Search Results: Records 1-13 displayed on this page of 13

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 ...

JAEA Reports

Clarification of debris formation conditions on the basis of the sampling data and experimental study using simulated fuel debris and reinforcement of the analytical results of severe accident scenario (Contract Research); FY2021 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; University of Fukui*

JAEA-Review 2022-046, 108 Pages, 2023/01

JAEA-Review-2022-046.pdf:6.25MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2021. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2021, this report summarizes the research results of the "Clarification of debris formation conditions on the basis of the sampling data and experimental study using simulated fuel debris and reinforcement of the analytical results of severe accident scenario" conducted in FY2021. The research on fuel debris so far is based on TMI-2 accident that is typical PWR accident but resent scenario analysis of sever accident progression and sampling data of the in reactor materials predict that fuel debris is diversity and piled up complicatedly depending on the unit and in reactor position. We are necessary to presume the thermodynamic condition of fuel debris during the accident in order to estimate accumulation state of debris.

Journal Articles

Structure, stability, and actinide leaching of simulated nuclear fuel debris synthesized from UO $_{2}$ , Zr, and stainless-steel

Kirishima, Akira*; Akiyama, Daisuke*; Kumagai, Yuta; Kusaka, Ryoji; Nakada, Masami; Watanabe, Masayuki; Sasaki, Takayuki*; Sato, Nobuaki*

Journal of Nuclear Materials, 567, p.153842_1 - 153842_15, 2022/08

https://doi.org/10.1016/j.jnucmat.2022.153842

Times Cited Count：5 Percentile：76.47(Materials Science, Multidisciplinary)

To understand the chemical structure and stability of nuclear fuel debris consisting of UO $_{2}$ , Zr, and Stainless Steel (SUS) generated by the Fukushima Daiichi Nuclear Power Plant accident in Japan in 2011, simulated debris of the UO $_{2}$ -SUS-Zr system and other fundamental component systems were synthesized and characterized. The simulated debris were synthesized by heat treatment for 1 to 12 h at 1600 $^{circ}$ C, in inert (Ar) or oxidative (Ar + 2% O $_{2}$ ) atmospheres. $^{237}$ Np and $^{241}$ Am tracers were doped for the leaching tests of these elements and U from the simulated debris. The characterization of the simulated debris was conducted by XRD, SEM-EDX, Raman spectroscopy, and Mssbauer spectroscopy, which provided the major uranium phase of the UO $_{2}$ -SUS-Zr debris was the solid solution of U $^{mathrm{IV}}$ O $_{2}$ (s.s.) with Zr(IV) and Fe(II) regardless of the treatment atmosphere. The long-term immersion test of the simulated debris in pure water and that in seawater revealed the macro scale crystal structure of the simulated debris was chemically very stable in the wet condition for a year or more. Furthermore, the leaching test results showed that the actinide leaching ratios of U, Np, Am from the UO $_{2}$ -SUS-Zr debris were very limited and less than 0.08 % for all the experiments in this study.

JAEA Reports

Basic research on the stability of fuel debris including alloy phase (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*

JAEA-Review 2022-009, 73 Pages, 2022/06

JAEA-Review-2022-009.pdf:2.08MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2020. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2018, this report summarizes the research results of the "Basic research on the stability of fuel debris including alloy phase" conducted from FY2018 to FY2021 (this contract was extended to FY2021). Since the final year of this proposal was FY2021, the results for four fiscal years were summarized. The present study focus on fuel debris consisting of oxide phase and alloy phase generated by the high temperature chemical reaction between structure materials (SUS pipes, pressure vessels, etc.) and fuels (melted fuels, claddings components, etc.). We synthesize the simulated debris of UO $_{2}$ -SUS system and UO $_{2}$ -Zr(ZrO $_{2}$ )-SUS system by high-temperature heat treatment, and measure their chemical property and dissolution behavior in water.

JAEA Reports

Basic research on the stability of fuel debris including alloy phase (Contract research); FY2019 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*

JAEA-Review 2020-032, 97 Pages, 2021/01

JAEA-Review-2020-032.pdf:4.16MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2019. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2018, this report summarizes the research results of the "Basic Research on the Stability of Fuel Debris Including Alloy Phase" conducted in FY2019. In the present study, we focus on fuel debris consisting of oxide phase and alloy phase generated by the high-temperature chemical reaction between structure materials (SUS pipes, pressure vessels, etc.) and fuels (melted fuels, claddings components, etc.). We synthesize the simulated debris of UO $_{2}$ -SUS system and UO $_{2}$ -Zr(ZrO $_{2}$ )-SUS system by high-temperature heat treatment, and measure their chemical property and dissolution behavior in water. Also, we will conduct research and development to spectroscopically analyze secular changes of oxide phase and alloy phase in the simulated debris.

JAEA Reports

Basic research on the stability of fuel debris including alloy phase (Contract research); FY2018 Center of World Intelligence Project for Nuclear Science/Technology and Human Resource Development

Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*

JAEA-Review 2019-035, 61 Pages, 2020/03

JAEA-Review-2019-035.pdf:2.9MB

JAEA/CLADS, had been conducting the Center of World Intelligence Project for Nuclear Science/Technology and Human Resource Development (hereafter referred to "the Project") in FY2018. The Project aims to contribute to solving problems in nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2018, this report summarizes the research results of the "Basic Research on the Stability of Fuel Debris Including Alloy Phase". In the present study, we focus on fuel debris consisting of oxide phase and alloy phase generated by the high-temperature chemical reaction between structure materials (SUS pipes, pressure vessels, etc.) and fuels (melted fuels, claddings components, etc.). We synthesize the simulated debris of UO $_{2}$ -SUS system and UO $_{2}$ -Zr(ZrO $_{2}$ )-SUS system by high-temperature heat treatment, and measure their chemical property and dissolution behavior in water. Also, we will conduct research and development to spectroscopically analyze secular changes of oxide phase and alloy phase in the simulated debris.

Journal Articles

Chlorination of UO $_{2}$ and (U,Zr)O $_{2}$ solid solution using MoCl $_{5}$

Sato, Takumi; Shibata, Hiroki; Hayashi, Hirokazu; Takano, Masahide; Kurata, Masaki

Journal of Nuclear Science and Technology, 52(10), p.1253 - 1258, 2015/10

https://doi.org/10.1080/00223131.2015.1070110

Times Cited Count：6 Percentile：45.66(Nuclear Science & Technology)

In order to explore the applicability of the chlorination by MoCl $_{5}$ as a potential pretreatment technique for waste treatment of fuel debris by pyrochemical methods, chlorination experiments of UO $_{2}$ and (U $_{0.5}$ Zr $_{0.5}$ )O $_{2}$ simulated fuel debris were carried out in two steps: the first one is a chlorination reaction by homogeneous heating, the second one is a volatilization of molybdenum by-product by heating under temperature gradient condition. Most of UO $_{2}$ and (U $_{0.5}$ Zr $_{0.5}$ )O $_{2}$ powder were converted to UCl $_{4}$ or UCl $_{4}$ and ZrCl $_{4}$ mixture at 573 K, respectively. In the case of (U $_{0.5}$ Zr $_{0.5}$ )O $_{2}$ sintered particle, most of sample was converted to the chlorides because the products evaporated and be separated from sample surface at 773 K, while only the surface of the sample disk was converted to the chlorides at 573 and 673 K. Most of molybdenum by-product and ZrCl $_{4}$ were separated from UCl $_{4}$ by volatilization at 573 K.

Journal Articles

Quench of molten aluminum oxide associated with in-vessel debris retention by RPV internal water

Maruyama, Yu; ; Moriyama, Kiyofumi; H.S.Park*; Kudo, Tamotsu; Y.Yang*; Sugimoto, Jun

NEA/CSNI/R(98)18, p.243 - 250, 1999/02

no abstracts in English

Journal Articles

Experiment and analysis on in-vessel debris coolability in ALPHA program

Maruyama, Yu; ; Moriyama, Kiyofumi; H.S.Park*; Kudo, Tamotsu; Y.Yang*; Sugimoto, Jun

JAERI-Conf 98-009, p.100 - 106, 1998/00

https://jopss.jaea.go.jp/pdfdata/JAERI-Conf-98-009.pdf

no abstracts in English

Journal Articles

Research plan on in-vessel debris coolability in ALPHA program

Maruyama, Yu; Yamano, Norihiro; Kudo, Tamotsu; Moriyama, Kiyofumi; Sugimoto, Jun

JAERI-memo 08-127, p.269 - 275, 1996/06

no abstracts in English

Journal Articles

Studies on in-vessel debris coolability in ALPHA program

Maruyama, Yu; Yamano, N.; Moriyama, Kiyofumi; H.S.Park*; Kudo, Tamotsu; Sugimoto, Jun

NUREG/CP-0157, 2, p.161 - 172, 1996/00

no abstracts in English

Oral presentation

Characterization of melt-solidified (U, Gd, Zr)O $_{2-x}$ as simulated corium debris

Morimoto, Kyoichi; Hirooka, Shun; Akashi, Masatoshi; Watanabe, Masashi

no journal, ,

The influence of Gd on characteristics of debris is important for removing the debris from the reactors of Fukushima Daiichi Nuclear Power Plant because subassemblies of nuclear fuels containing Gd $_{2}$ O $_{3}$ were loaded in the some reactor cores. Additionally, it is important to assess the distribution state of Gd from the anxiety of re-criticality caused by the relocation of debris while removing them. In this study, sintered pellets of (U $_{0.95-y}$ Gd $_{0.05}$ Zr $_{y}$ )O $_{2-x}$ (y=0,0.5, 2-x=1.989-2.000) were melted and solidified to prepare specimens of simulated corium debris. Phase states and fundamental properties of them were evaluated.

Oral presentation

Solidification behavior of the simulated oxide debris

Sudo, Ayako; Mizusako, Fumiki*; Hoshino, Kuniyoshi*; Sato, Takumi; Nagae, Yuji; Kurata, Masaki

no journal, ,

Oral presentation

The Possible use of short half-life noble gas fission products for measurement of criticality and identification of plutonium in fuel debris canister

Riyana, E. S.; Okumura, Keisuke; Sakamoto, Masahiro; Matsumura, Taichi; Terashima, Kenichi

no journal, ,