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JAEA Reports

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2020 (Operation, utilization and technical development of JRR-3, JRR-4, NSRR, Tandem Accelerator, RI Production Facility and Tritium Process Laboratory)

Department of Research Reactor and Tandem Accelerator

JAEA-Review 2022-075, 112 Pages, 2023/03

JAEA-Review-2022-075.pdf:8.25MB

The Department of Research Reactor and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3 (Japan Research Reactor No.3), JRR-4 (Japan Research Reactor No.4), NSRR (Nuclear Safety Research Reactor), Tandem Accelerator, RI Production Facility, TPL (Tritium Process Laboratory) and FEL (Free Electron Laser). This annual report describes the activities of our department in fiscal year of 2020. We carried out the operation and maintenance, utilization, upgrading of utilization techniques, safety administration and international cooperation. Also contained are lists of publications, meetings, granted permissions on laws and regulations concerning atomic energy, outcomes in service and technical developments and so on.

JAEA Reports

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2019 (Operation, Utilization and Technical Development of JRR-3, JRR-4, NSRR, Tandem Accelerator, RI Production Facility and Tritium Process Laboratory)

Department of Research Reactor and Tandem Accelerator

JAEA-Review 2022-064, 97 Pages, 2023/02

JAEA-Review-2022-064.pdf:2.91MB

The Department of Research Reactor and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3 (Japan Research Reactor No.3), JRR-4 (Japan Research Reactor No.4), NSRR (Nuclear Safety Research Reactor), Tandem Accelerator, RI Production Facility and TPL(Tritium Process Laboratory). This annual report describes the activities of our department in fiscal year of 2019. We carried out the operation and maintenance, utilization, upgrading of utilization techniques, safety administration and international cooperation. Also contained are lists of publications, meetings, granted permissions on laws and regulations concerning atomic energy, outcomes in service and technical developments and so on.

JAEA Reports

Annual report of Nuclear Science Research Institute, JFY2017

Nuclear Science Research Institute, Sector of Nuclear Science Research

JAEA-Review 2021-067, 135 Pages, 2022/03

JAEA-Review-2021-067.pdf:7.31MB

Nuclear Science Research Institute (NSRI) is composed of Planning and Coordination Office and six departments, namely Department of Operational Safety Administration, Department of Radiation Protection, Engineering Services Department, Department of Research Reactor and Tandem Accelerator, Department of Fukushima Technology Development and Department of Decommissioning and Waste Management, and each departments manage facilities and develop related technologies to achieve the "Middle-term Plan" successfully and effectively. In order to contribute the future research and development and to promote management business, this annual report summarizes information on the activities of NSRI of JFY 2017 as well as the activity on research and development carried out by the Nuclear Safety Research Center, Advanced Science Research Center, Nuclear Science and Engineering Center, Materials Sciences Research Center, and development activities of Nuclear Human Resources Development Center, using facilities of NSRI.

JAEA Reports

Annual report of Nuclear Science Research Institute, JFY2015 & 2016

Nuclear Science Research Institute

JAEA-Review 2021-006, 248 Pages, 2021/12

JAEA-Review-2021-006.pdf:7.17MB

Nuclear Science Research Institute (NSRI) is composed of Planning and Coordination Office and six departments, namely Department of Operational Safety Administration, Department of Radiation Protection, Engineering Services Department, Department of Research Reactor and Tandem Accelerator, Department of Fukushima Technology Development and Department of Decommissioning and Waste Management, and each department manages facilities and develops related technologies to achieve the "Middle and long-term Plan" successfully and effectively. In order to contribute the future research and development and to promote management business, this annual report summarizes information on the activities of NSRI of JFY 2015 and 2016 as well as the activity on research and development carried out by Nuclear Safety Research Center, Advanced Science Research Center, Nuclear Science and Engineering Center, Material Science Research Center, and development activities of Nuclear Human Resources Development Center, using facilities of NSRI.

JAEA Reports

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2018 (Operation, utilization and technical development of JRR-3, JRR-4, NSRR, Tandem Accelerator, RI Production Facility and Tritium Process Laboratory)

Department of Research Reactor and Tandem Accelerator

JAEA-Review 2020-074, 105 Pages, 2021/03

JAEA-Review-2020-074.pdf:3.72MB

The Department of Research Reactor and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3 (Japan Research Reactor No.3), JRR-4 (Japan Research Reactor No.4), NSRR (Nuclear Safety Research Reactor), Tandem Accelerator, RI Production Facility and TPL (Tritium Process Laboratory). This annual report describes the activities of our department in fiscal year of 2018. We carried out the operation and maintenance, utilization, upgrading of utilization techniques, safety administration and international cooperation. Also contained are lists of publications, meetings, granted permissions on laws and regulations concerning atomic energy, outcomes in service and technical developments and so on.

JAEA Reports

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2017 (Operation, utilization and technical development of JRR-3, JRR-4, NSRR, Tandem Accelerator, RI Production Facility and Tritium Process Laboratory)

Department of Research Reactor and Tandem Accelerator

JAEA-Review 2020-073, 113 Pages, 2021/03

JAEA-Review-2020-073.pdf:3.87MB

The Department of Research Reactor and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3 (Japan Research Reactor No.3), JRR-4 (Japan Research Reactor No.4), NSRR (Nuclear Safety Research Reactor), Tandem Accelerator, RI Production Facility and Tritium Process Laboratory. This annual report describes the activities of our department in fiscal year of 2017. We carried out the operation and maintenance, utilization, upgrading of utilization techniques, safety administration and international cooperation. Also contained are lists of publications, meetings, granted permissions on laws and regulations concerning atomic energy, outcomes in service and technical developments and so on.

JAEA Reports

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2016 (Operation, utilization and technical development of JRR-3, JRR-4, NSRR, Tandem Accelerator, RI Production Facility and Tritium Process Laboratory)

Department of Research Reactor and Tandem Accelerator

JAEA-Review 2020-072, 102 Pages, 2021/03

JAEA-Review-2020-072.pdf:3.86MB

The Department of Research Reactor and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3 (Japan Research Reactor No.3), JRR-4 (Japan Research Reactor No.4), NSRR (Nuclear Safety Research Reactor), Tandem Accelerator, RI Production Facility and Tritium Process Laboratory). This annual report describes the activities of our department in fiscal year of 2016. We carried out the operation and maintenance, utilization, upgrading of utilization techniques, safety administration and international cooperation. Also contained are lists of publications, meetings, granted permissions on laws and regulations concerning atomic energy, outcomes in service and technical developments and so on.

JAEA Reports

Annual report of Nuclear Science Research Institute, JFY2013 & 2014

Nuclear Science Research Institute

JAEA-Review 2018-036, 216 Pages, 2019/03

JAEA-Review-2018-036.pdf:19.22MB

Nuclear Science Research Institute (NSRI) is composed of Planning and Coordination Office, Fukushima Project Team and six departments, namely Department of Operational Safety Administration, Department of Radiation Protection, Engineering Services Department, Department of Research Reactor and Tandem Accelerator, Department of Fukushima Technology Development and Department of Decommissioning and Waste Management, and each departments manage facilities and develop related technologies to achieve the "Middle-term Plan" successfully and effectively. In order to contribute the future research and development and to promote management business, this annual report summarizes information on the activities of NSRI of JFY 2013 and 2014 as well as the activity on research and development carried out by Nuclear Safety Research Center, Advanced Research Center, Nuclear Science and Engineering Center and Quantum Beam Science Center, and activity of Nuclear Human Resource Development Center, using facilities of NSRI.

Journal Articles

Effect of hydrocarbons on the efficiency of catalytic reactor of detritiation system in an event of fire

Edao, Yuki; Sato, Katsumi; Iwai, Yasunori; Hayashi, Takumi

Journal of Nuclear Science and Technology, 53(11), p.1831 - 1838, 2016/11

 Times Cited Count:7 Percentile:60.71(Nuclear Science & Technology)

Journal Articles

Upgrade in catalytic activity of hydrophobic platinum catalysts by irradiation with electron beams

Iwai, Yasunori

Fusion Engineering and Design, 98-99, p.1796 - 1799, 2015/10

 Times Cited Count:5 Percentile:40.2(Nuclear Science & Technology)

Hydrophobic platinum catalysts have been widely applied in the field of nuclear fusion for the exchange reactions of hydrogen isotopes between hydrogen and vapor in the water detritiation system, and for the oxidation of tritium on the atmospheric detritiation system. Hydrophobic platinum catalysts are hardly susceptible to water mist and water vapor. Hydrophobic platinum catalysts are produced by supporting platinum directly on hydrophobic polymer beads. For the hydrophobic polymer, styrene - divinyl benzene (SDB) has been applied in Japan. It can be pointed out that the upgrade in catalytic activity of hydrophobic catalyst is expected to downsize the catalytic reactor based on a hard look at a large increase in flow rate in future. The upgrade in catalytic activity of two types of commercial Pt/SDB catalysts was found when they were irradiated with electron beams. After irradiation with electron beams, the catalytic activity was evaluated by means of overall reaction rate constant for the oxidation of tritium. The overall reaction rate constant increased as increase in dose. The constant showed the peak value in the dose between 500 to 1000 kGy. After the peak, the constant decreased as increase in dose. The overall reaction rate constant at the peak was 6 times larger than that evaluated with unirradiated. The mechanical strength of irradiated Pt/SDB kept sound until 1500 kGy. The irradiation is a promising method to the upgrading in catalytic activity of Pt/SDB catalyst.

Journal Articles

Hydrophobic platinum honeycomb catalyst to be used for tritium oxidation reactors

Iwai, Yasunori; Kubo, Hitoshi*; Oshima, Yusuke*; Noguchi, Hiroshi*; Edao, Yuki; Taniuchi, Junichi*

Fusion Science and Technology, 68(3), p.596 - 600, 2015/10

 Times Cited Count:2 Percentile:17.75(Nuclear Science & Technology)

We have newly developed the hydrophobic platinum honeycomb catalysts applicable to tritium oxidation reactor since the honeycomb-shape catalyst can decrease the pressure drop. Two types of hydrophobic honeycomb catalyst have been test-manufactured. One is the hydrophobic platinum catalyst on a metal honeycomb. The other is the hydrophobic platinum catalyst on a ceramic honeycomb made of silicon carbide. The fine platinum particles around a few nanometers significantly improve the catalytic activity for the oxidation tritium at a tracer concentration. The hydrogen concentration in the gaseous feed slightly affects the overall reaction rate constant for hydrogen oxidation. Due to the competitive adsorption of hydrogen and water molecules on platinum surface, the overall reaction rate constant has the bottom value. The hydrogen concentration for the bottom value is 100 ppm under the dry feed gas. We have experimentally confirmed the activity of these honeycomb catalysts is as good as that of pellet-shape hydrophobic catalyst. The results support the hydrophobic honeycomb catalysts are applicable to tritium oxidation reactor.

Journal Articles

Catalyst technology of Tanaka Kikinzoku Kogyo

Kubo, Hitoshi*; Oshima, Yusuke*; Iwai, Yasunori

JETI, 63(10), p.33 - 36, 2015/09

Tanaka Kikinzoku Kogyo provides a broad range of precious metals products and technologies. Tanaka Kikinzoku Kogyo and Japan Atomic Energy Agency have jointly developed a new method of manufacturing catalysts involving hydrophobic processing with an inorganic substance base. As a result, previous technological issues were able to be solved with the development of a catalyst that exhibited no performance degradation in response to radiation application of 530 kGy, a standard for radiation resistance, and maintenance of thermal stability at over 600$$^{circ}$$C, which is much higher than the 70$$^{circ}$$C temperature that is normally used. The application of this catalyst to the liquid phase catalytic exchange process is expected to overcome significant technological hurdles with regards to improving the reliability and efficiency of systems for collecting tritium from tritiated water. It is also anticipated that the hydrophobic platinum catalyst manufacturing technology used for this catalyst could be applied to a wide range of fields other than nuclear fusion research. It was verified that if applied to a hydro oxidation catalyst, hydrogen could be efficiently oxidized, even at room temperature. This catalyst can also contribute to improving safety at non-nuclear plants that use hydrogen in general by solving the aforementioned vulnerability issue.

Journal Articles

Development of hydrophobic platinum catalyst for the effective collection of tritium in fusion plants

Iwai, Yasunori; Kubo, Hitoshi*; Oshima, Yusuke*

Isotope News, (736), p.12 - 17, 2015/08

We have successfully developed a new hydrophobic platinum catalyst for collecting tritium at nuclear fusion reactors. Catalysts used to collect tritium are called hydrophobic precious metal catalysts. In Japan, hydrophobic precious metal catalysts manufactured from polymers have been used for heavy water refinement.However, this catalyst has issues related to embrittlement to radiation and thermal stability. These technological issues needed to be solved to allow for its application to nuclear fusion reactors requiring further enrichment from highly-concentrated tritiated water. We developed a new method of manufacturing catalysts involving hydrophobic processing with an inorganic substance base. As a result, previous technological issues were able to be solved with the development of a catalyst that exhibited no performance degradation in response to radiation application of 530kGy, a standard for radiation resistance, and maintenance of thermal stability at over 600$$^{circ}$$C, which is much higher than the 70$$^{circ}$$C temperature that is normally used. The catalyst created with this method was also confirmed to have achieved the world's highest exchange efficiency, equivalent to 1.3 times the previously most powerful efficiency. The application of this catalyst to the liquid phase catalytic exchange process is expected to overcome significant technological hurdles with regards to improving the reliability and efficiency of systems for collecting tritium from tritiated water.

Journal Articles

Successful development of a new catalyst for efficiently collecting tritium; A Breakthrough toward realization of fusion reactors

Iwai, Yasunori; Kubo, Hitoshi*; Oshima, Yusuke*

Kagaku, 70(5), p.35 - 40, 2015/05

We have successfully developed a new hydrophobic platinum catalyst for collecting tritium at nuclear fusion reactors. Catalysts used to collect tritium are called hydrophobic precious metal catalysts. In Japan, hydrophobic precious metal catalysts manufactured from polymers have been used for heavy water refinement. However, this catalyst has issues related to embrittlement to radiation and thermal stability. These technological issues needed to be solved to allow for its application to nuclear fusion reactors requiring further enrichment from highly-concentrated tritiated water. We developed a new method of manufacturing catalysts involving hydrophobic processing with an inorganic substance base. As a result, previous technological issues were able to be solved with the development of a catalyst that exhibited no performance degradation in response to radiation application of 530 kGy, a standard for radiation resistance, and maintenance of thermal stability at over 600$$^{circ}$$C, which is much higher than the 70$$^{circ}$$C temperature that is normally used. The catalyst created with this method was also confirmed to have achieved the world's highest exchange efficiency, equivalent to 1.3 times the previously most powerful efficiency. The application of this catalyst to the liquid phase catalytic exchange process is expected to overcome significant technological hurdles with regards to improving the reliability and efficiency of systems for collecting tritium from tritiated water.

Journal Articles

Recent progress on tritium technology research and development for a fusion reactor in Japan Atomic Energy Agency

Hayashi, Takumi; Nakamura, Hirofumi; Kawamura, Yoshinori; Iwai, Yasunori; Isobe, Kanetsugu; Yamada, Masayuki; Suzuki, Takumi; Kurata, Rie; Oyaizu, Makoto; Edao, Yuki; et al.

Fusion Science and Technology, 67(2), p.365 - 370, 2015/03

 Times Cited Count:1 Percentile:9.79(Nuclear Science & Technology)

Journal Articles

Measurement of tritium penetration through concrete material covered by various paints coating

Edao, Yuki; Kawamura, Yoshinori; Kurata, Rie; Fukada, Satoshi*; Takeishi, Toshiharu*; Hayashi, Takumi; Yamanishi, Toshihiko

Fusion Science and Technology, 67(2), p.320 - 323, 2015/03

 Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)

The present study aims at obtaining fundamental knowledge for tritium transfer behavior and interaction between tritium and paint coated on concrete walls. The amounts of tritium penetration and release in cement paste with epoxy and urethane paint coatings were measured. The tritium penetration amounts were increased with the HTO exposure time. Time to achieve each saturate tritium value was more than 60 days for cement paste coated with epoxy paint and with urethane paint, while cement paste without paint took 2 days to achieve it. Tritium penetration rates were estimated by an analysis of diffusion model. Although their paint coatings were effective for reduction of tritium penetration through the cement paste exposed to HTO for a short period, the amount of tritium trapped in the paints became large for a long time. This work has been performed under the collaboration research between JAEA and Kyushu University.

Journal Articles

Correlation of rates of tritium migration through porous concrete

Fukada, Satoshi*; Katayama, Kazunari*; Takeishi, Toshiharu*; Edao, Yuki; Kawamura, Yoshinori; Hayashi, Takumi; Yamanishi, Toshihiko

Fusion Science and Technology, 67(2), p.99 - 102, 2015/03

 Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)

Journal Articles

Investigation on degradation mechanism of ion exchange membrane immersed in highly concentrated tritiated water under the Broader Approach activities

Iwai, Yasunori; Sato, Katsumi; Yamanishi, Toshihiko

Fusion Engineering and Design, 89(7-8), p.1534 - 1538, 2014/10

 Times Cited Count:7 Percentile:53.55(Nuclear Science & Technology)

The ion exchange membrane such as Nafion is a key material for electrolysis cells of the Water Detritiation System. Long-term exposure of Nafion ion exchange membrane into 1.38$$times$$10$$^{12}$$Bq/kg of tritiated water was conducted at room temperature for up to 2 years. The ionic conductivity of Nafion ion exchange membrane after immersed in tritiated water was changed. The change in color of membrane from colorless to yellowish was caused by active radical reactions. Infrared Fourier transform spectrum of the membrane immersed in tritiated water revealed a small peak for bending vibration of C-H situated at 1437 cm$$^{-1}$$ demonstrating the formation of hydrophobic functional group in the membrane. The high-resolution solid state $$^{19}$$F NMR spectrum of the membrane after immersed in tritiated water was similar to that of membrane irradiated with $$gamma$$-rays. From the $$^{19}$$F NMR spectrum, any distinctive degradation in the membrane structure by interaction with tritium was not measured.

Journal Articles

Penetration of tritiated water vapor through hydrophobic paints for concrete materials

Edao, Yuki; Kawamura, Yoshinori; Yamanishi, Toshihiko; Fukada, Satoshi*

Fusion Engineering and Design, 89(9-10), p.2062 - 2065, 2014/10

 Times Cited Count:4 Percentile:31.13(Nuclear Science & Technology)

Tritium transfer behavior through hydrophobic paints, epoxy resin and acrylic-silicon resin, was investigated experimentally. The authors measured the amount of tritium permeated through the paint membranes which exposed in HTO atmosphere of 2$$sim$$100 Bq/cm$$^{3}$$. The most of tritium permeated through the paints in the form of HTO at room temperature. Tritium permeation through the acrylic-silicon paint was explained a linear sorption/release model and that through the epoxy paint was suggested to be controlled by a one-dimensional diffusion model. While effective diffusivity was 1.0$$times$$10$$^{-13}$$$$sim$$1.8$$times$$10$$^{-13}$$ m$$^{2}$$/s at 21$$^{circ}$$C$$sim$$26$$^{circ}$$C for epoxy membrane, the diffusivity was found to be hundreds times larger than that for cement-paste coated with epoxy paint. Hence, tritium diffusivity through interface between cement-paste and the epoxy paint was considered to be most effective in the overall tritium transfer process. Tritium transfer behavior in the interface is important to explain the mechanism of tritium transfer behavior in concrete walls.

Journal Articles

Hydrogen and water vapor adsorption properties on cation-exchanged mordenite for use to a tritium recovery system

Kawamura, Yoshinori; Edao, Yuki; Iwai, Yasunori; Hayashi, Takumi; Yamanishi, Toshihiko

Fusion Engineering and Design, 89(7-8), p.1539 - 1543, 2014/10

 Times Cited Count:7 Percentile:53.55(Nuclear Science & Technology)

Tritium recovery system using adsorption or catalytic isotope exchange has already been proposed for a solid breeding blanket system of a nuclear fusion reactor. Synthetic zeolite is often used as an adsorbent or a substrate of chemical exchange catalyst. And, it is well known that its properties are changed easily by exchanging their cations. So, in this work, adsorption capacities of hydrogen isotope and water vapor on cation-exchanged mordenite with transition metal ion were investigated. Ag ion-exchanged mordenite (Ag-MOR) has indicated considerably large hydrogen adsorption capacity in lower pressure range at 77 K. And, adsorption capacity of water vapor did not so vary with exchaned cation in comparison with hydrogen adsorption. The discussion from the viewpoint of adsorption rate is still remaining, but more compact cryosorption column for tritium recovery system is possible to design if Ag-MOR is adopted.

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