Development of a cooperative operation robot system for radiation source exploration (Contract research); FY2022 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*

JAEA-Review 2023-030, 80 Pages, 2024/03

JAEA-Review-2023-030.pdf:4.96MB

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 FY2022. 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 "Development of a cooperative operation robot system for radiation source exploration" conducted in FY2022. The present study aims to develop a Cooperative Operation Robot system for RAdiation Source Exploration (CORRASE). The multiple robot system provides radiation source exploration with wide field of view, rapidity, and low cost. The radiation source exploration is realized with multiple robots carrying directional gamma-ray detectors determining the incident direction of the incoming gamma-rays. We will develop the system by the final year of this proposal aiming for application in the Fukushima Daiichi Nuclear Power Station.

Rapid multi-nuclide identification method by simultaneous , , and X-ray spectrum analysis

Oshima, Masumi*; Goto, Jun*; Hayakawa, Takehito*; Asai, Masato; Kin, Tadahiro*; Shinohara, Hirofumi*

Isotope News, (790), p.19 - 23, 2023/12

When analyzing samples that contain many radionuclides at various concentrations, such as radioactive waste or fuel debris, it is difficult to apply general spectrum analysis methods and is necessary to chemically separate each nuclide before quantifying it. The chemical separation is especially essential for analysis using a liquid scintillation counter (LSC). In this report, the authors explain the newly developed spectral determination method (SDM) in which the entire spectrum is fitted to quantify radioactivity of nuclides mixed in a sample. By applying the SDM to - and X-ray spectrum measured by LSC and -ray spectrum measured by Ge detector simultaneously, the authors demonstrated that radioactivity of 40 radionuclides mixed in a sample at concentrations varying by two orders could be quantified, which is useful to simplify chemical separation process in radionuclide quantification.

Development of thin SiC neutron detector with high radiation resistance (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Kyoto University*

JAEA-Review 2022-068, 90 Pages, 2023/05

JAEA-Review-2022-068.pdf:3.55MB

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 "Development of thin SiC neutron detector with high radiation resistance" 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. In the works for debris retrieval, it is required to install subcritical surveillance radiation monitors that can surely work for long time under extremely high gamma-ray radiation environment. However, there have been problems such as remote control of conventional neutron detectors is difficult because heavy radiation shields are needed.

Actual stress analysis of small-bore butt-welded pipe by complementary use of synchrotron X-rays and neutrons

Suzuki, Kenji*; Miura, Yasufumi*; Shiro, Ayumi*; Toyokawa, Hidenori*; Saji, Choji*; Shobu, Takahisa; Morooka, Satoshi

Zairyo, 72(4), p.316 - 323, 2023/04

https://doi.org/10.2472/jsms.72.316

Development of a cooperative operation robot system for radiation source exploration (Contract research); FY2021 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*

JAEA-Review 2022-041, 76 Pages, 2023/01

JAEA-Review-2022-041.pdf:3.27MB

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 "Development of a cooperative operation robot system for radiation source exploration" conducted in FY2021. The present study aims to develop a Cooperative Operation Robot system for RAdiation Source Exploration (CORRASE). The multiple robot system provides radiation source exploration with wide field of view, rapidity, and low cost. The radiation source exploration is realized with multiple robots carrying directional gamma-ray detectors determining the incident direction of the incoming gamma-rays. We will develop the system by the final year of this proposal aiming for application in the Fukushima Daiichi Nuclear Power Station.

Crystal configuration dependence of CsI(Tl) scintillation detectors on environmental dose rate measurement

Tsuda, Shuichi; Saito, Kimiaki

Radiation Protection Dosimetry, 198(17), p.1283 - 1291, 2022/10

https://doi.org/10.1093/rpd/ncac157

Spherical or cylindrical detectors superior to directional characteristic are commonly used to monitor dose rates in the environment to detect scattering gamma-rays emitted from radionuclides in soil or air. The authors have performed environmental dose rates measurements using various kinds of detectors to investigate the directional characteristics, and experimentally verified the variations in dose rates due to directional characteristics unique to each detector. Furthermore, a dose rate measured by a CsI(Tl) scintillation detector with cuboidal crystal agreed with that by a CsI(Tl) scintillation detector with cylindrical crystal. Simulations by PHITS under various CsI(Tl) crystal configurations revealed that there are certain aspect ratios of cuboidal CsI(Tl) crystal with less directional dependence. Since cubes are advantageous in terms of production cost, this result indicates the potential of CsI(Tl) scintillation detectors with cuboidal crystal for use in the environmental dose rate monitoring.

Analysis of microparticles generated by laser processing and development of a methodology for their nuclear identification (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; The University of Tokyo*

JAEA-Review 2022-015, 119 Pages, 2022/09

JAEA-Review-2022-015.pdf:6.62MB

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 "Analysis of microparticles generated by laser processing and development of a methodology for their nuclear identification" 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. Although laser processing has various advantages, one well-known disadvantage is that it generates a large amount of microparticles during the processing. Therefore, the application of laser processing to decommissioning waste contaminated with radioactive materials has been hesitant because the mechanism generating the microparticles has not been fully understood.

Research and development of the sample-return technique for fuel debris using the unmanned underwater vehicle (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; National Institute of Maritime, Port and Aviation Technology*

JAEA-Review 2021-049, 67 Pages, 2022/01

JAEA-Review-2021-049.pdf:7.54MB

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 FY2020, this report summarizes the research results of the "Research and development of the sample-return technique for fuel debris using the unmanned underwater vehicle" conducted in FY2020. The present study aims to develop a fuel debris sampling device that comprises a neutron detector with radiation resistance and enhanced neutron detection efficiency, an end-effector with powerful cutting and collection capabilities, and a manipulator under the Japan-UK joint research team. We will also develop a fuel debris sampling system that can be mounted on an unmanned vehicle. In addition, we will develop a positioning system to identify the system position, and a technique to project the counting information of optical cameras, sonar, …

Technology development of diamond-base neutron sensors and radiation-resistive integrated-circuits for shielding-free criticality approach monitoring system (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; High Energy Accelerator Research Organization*

JAEA-Review 2021-038, 65 Pages, 2022/01

JAEA-Review-2021-038.pdf:4.42MB

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 FY2020, this report summarizes the research results of the "Technology development of diamond-base neutron sensors and radiation-resistive integrated-circuits for shielding-free criticality approach monitoring system" conducted in FY2020. The present study aims to develop key components of neutron detection system without a radiation shield for a criticality approach monitoring system. It is required high neutron detection efficiency for a few cps/nv under high gamma ray radiation environment (i.e. 1 kGy/h maximum) and compact-light-weight to fit constraints of the penetration size and the payload.

Development of radiation hardened diamond image sensing devices (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; National Institute of Advanced Industrial Science and Technology*

JAEA-Review 2021-026, 47 Pages, 2021/11

JAEA-Review-2021-026.pdf:2.16MB

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 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 FY2019, this report summarizes the research results of the "Development of radiation hardened diamond image sensing devices" conducted in FY2020. The research objective of this project is to develop image sensing devices which work under the high radiation condition. The devices will be realized using radiation hardened diamond semiconductor devices as charge transfer devices and photodetectors. The research project has mainly two targets such as to confirm charge coupled devices operation on diamond unipolar devices and to characterize photo conductivity of diamond detectors.