Development of the solid waste a management system

Shimomura, Yusuke; Sugiyama, Tatsuya; Abe, Kazuyuki

JAEA-Testing 2024-003, 128 Pages, 2025/01

JAEA-Testing-2024-003.pdf:4.26MB

At the Waste Management Facilities of the Japan Atomic Energy Agency Oarai Research and Development (R&D) Institute, radioactive waste generated from the Oarai R&D Institute and nearby facilities is accepted, incinerated, compressed, repackaged, and then sealed in disposal containers for storage and management. To manage information on the properties, processing, and storage of this waste, an information management system is planned to be developed for each waste category. As the first phase, an information management system for solid waste A was developed over three years from FY 2019 to FY 2021. This document describes the functions of the constructed information management system for solid waste A and summarizes its operation in actual waste processing.

Simulation of predicted effects of decontamination and cultivation activities on reduction of air dose rates using Monte Carlo method

Kim, M.; Yoshimura, Kazuya; Sakuma, Kazuyuki; Malins, A.*; Abe, Tomohisa; Nakama, Shigeo; Machida, Masahiko; Saito, Kimiaki

Kankyo Hoshano Josen Gakkai-Shi, 12(2), p.39 - 53, 2024/04

More than ten years have passed since the accident at TEPCO's Fukushima Daiichi Nuclear Power Station. But with the progress of decontamination, the evacuation order has been lifted and the return of residents is still ongoing. Under these circumstances, in order to quantitatively evaluate the effect of decontamination activities and cultivation on air dose rate reduction, a detailed environmental model was constructed using 3D-ADRES for a real area located in the Okuma town, Fukushima prefecture. Monte Carlo simulations were performed using the model to calculate realistic distributions of radioactive Cs based on measurement results and air dose rates reflecting changes over time. As a result, the distribution of air dose rates at 100 cm above ground level in the target area according to decontamination and cultivation activities was calculated. The calculated air dose rates reproduced the measured values well, and were confirmed to be appropriate as a method for evaluating the effects of decontamination and cultivation activities. This method is expected to serve as a reference for further decontamination management measures to reduce the air dose rate in the difficult-to-return zone, where entry is still restricted.

Theoretical study of deuteron-induced reactions in the nuclear data field

Nakayama, Shinsuke; Iwamoto, Osamu; Watanabe, Yukinobu*; Ogata, Kazuyuki*

Few-Body Systems, 63(1), p.4_1 - 4_6, 2022/03

https://doi.org/10.1007/s00601-021-01712-2

Intensive neutron sources using deuteron accelerators have been proposed for not only science and engineering fields but also medical applications. For the engineering design of such facilities, accurate and comprehensive nuclear data of deuteron-induced reactions are indispensable. However, it is difficult to meet the requirement by employing experimental data alone. Thus, theoretical model calculations play a key role in completing the necessary nuclear data by interpolation and extrapolation of experimental data. Under the above situations, we have been developing a code system dedicated for deuteron-induced reactions, called DEURACS. In the present work, calculations using DEURACS are compared with available experimental data and validation of the present modelling in DEURACS is discussed. Moreover, the importance of consideration of the breakup processes for accurate prediction of deuteron-induced reactions is also presented.

JENDL/DEU-2020; Deuteron nuclear data library for design studies of accelerator-based neutron sources

Nakayama, Shinsuke; Iwamoto, Osamu; Watanabe, Yukinobu*; Ogata, Kazuyuki*

Journal of Nuclear Science and Technology, 58(7), p.805 - 821, 2021/07

https://doi.org/10.1080/00223131.2020.1870010

Intensive fast neutron sources using deuteron accelerators have been proposed for various applications. To contribute to the design study of such neutron sources, a deuteron nuclear data library for Li, Be, and C up to 200 MeV, JENDL/DEU-2020 is developed. The evaluation of JENDL/DEU-2020 are performed by employing the code system DEURACS with particular attention to neutron production data. Toward the evaluation of JENDL/DEU-2020, some modifications are made to DEURACS. The validation of the library is performed though simulation with the Monte Carlo transport calculation codes. From the simulation, it is shown that the calculation results based on JENDL/DEU-2020 reproduce the measured neutron production data well in the incident energies up to 200 MeV. The new library is expected to make a large contribution to diverse design studies of deuteron accelerator neutron sources.

Study on the evaluation method to determine the radioactivity concentration in radioactive waste on Oarai Research and Development Institute (FY2019)

Asakura, Kazuki; Shimomura, Yusuke; Donomae, Yasushi; Abe, Kazuyuki; Kitamura, Ryoichi

JAEA-Review 2020-015, 66 Pages, 2020/09

JAEA-Review-2020-015.pdf:4.27MB

The disposal of radioactive waste from the research facility need to calculated from the radioactivity concentration that based on variously nuclear fuels and materials. In Japan Atomic Energy Oarai Research and Development Institute, the study on considering disposal is being advanced among the facilities which generate radioactive waste as well as the facilities which process radioactive waste. This report summarizes a study result in FY2019 about the evaluation method to determine the radioactivity concentration in radioactive waste on Oarai Research and Development Institute.

Anomalous radioisotope production for ZnO using polyethylene by accelerator neutrons

Tsukada, Kazuaki; Nagai, Yasuki*; Hashimoto, Shintaro; Minato, Futoshi; Kawabata, Masako*; Hatsukawa, Yuichi*; Hashimoto, Kazuyuki*; Watanabe, Satoshi*; Saeki, Hideya*; Motoishi, Shoji*

Journal of the Physical Society of Japan, 89(3), p.034201_1 - 034201_7, 2020/03

https://doi.org/10.7566/JPSJ.89.034201

We found anomalously large yields of Ga, Ga, Zn and Cu by neutron irradiation on a ZnO sample in a polyethylene shield. Neutron beams are generated from the Be() reaction for 50 MeV deuterons. The yields obtained were more than 20 times larger than those in the unshielded sample. On the other hand, the yields of Ga, Ga, Zn and Cu from a metallic Zn sample and the yields of Cu, Ni and Zn from the ZnO and Zn samples were almost insensitive to the shield conditions. This finding would provide us a unique capability of accelerator neutrons to simultaneously produce a large amount of several radioisotopes, including proton induced reaction products, by using a single sample. The experimental data were compared with the yields estimated by using the Particle and Heavy Ion Transport code System and the result was discussed.

Application of JSME Seismic Code Case by elastic-plastic response analysis to practical piping system

Otani, Akihito*; Kai, Satoru*; Kaneko, Naoaki*; Watakabe, Tomoyoshi; Ando, Masanori; Tsukimori, Kazuyuki*

Proceedings of 2018 ASME Pressure Vessels and Piping Conference (PVP 2018), 10 Pages, 2018/07

This paper demonstrates an application result of the JSME Seismic Code Case to an actual complex piping system. The secondary coolant piping system of Japanese Fast Breeder Reactor, Monju, was selected as a representative of the complex piping systems. The elastic-plastic time history analysis for the piping system was performed and the piping system has been evaluated according to the JSME Seismic Code Case. The evaluation by the Code Case provides a reasonable result in terms of the piping fatigue evaluation that governs seismic integrity of piping systems.

Development of a code system DEURACS for theoretical analysis and prediction of deuteron-induced reactions

Nakayama, Shinsuke; Kono, Hiroshi*; Watanabe, Yukinobu*; Iwamoto, Osamu; Ye, T.*; Ogata, Kazuyuki*

EPJ Web of Conferences, 146, p.12025_1 - 12025_4, 2017/09

https://doi.org/10.1051/epjconf/201714612025

Recently, intensive neutron sources using deuteron accelerator have been proposed for various applications. Accurate and comprehensive deuteron nuclear data library over wide ranges of target mass number and incident energy are indispensable for the design of deuteron accelerator neutron sources. Thus, we have developed an integrated code system dedicated for analysis and prediction of deuteron-induced reactions, which is called DEUteron-induced Reaction Analysis Code System (DEURACS). In the present work, the analysis of reactions is extended to higher incident energy up to nearly 100 MeV and also DEURACS is applied to reactions at 80 and 100 MeV. The DEURACS calculations reproduce the experimental double-differential cross sections for the and reactions well.

Analysis of reactions on Be and C

Nakayama, Shinsuke; Kono, Hiroshi*; Watanabe, Yukinobu*; Iwamoto, Osamu; Ogata, Kazuyuki*

RCNP Annual Report 2016 (Internet), 2 Pages, 2017/05

http://www.rcnp.osaka-u.ac.jp/~annurep/2016/ResearchReport/2TheoreticalPhysics/nakayamaS_2_2016.pdf

We are conducting a theoretical research on deuteron-induced reaction together with Kyushu University and Research Center for Nuclear Physics (RCNP) of Osaka University. The research outcomes achieved in fiscal year 2016 are summarized as a part of the annual report of RCNP. In recent years, accelerator neutron sources using reactions on light nuclei (Li, Be, C, etc.) are proposed for applications in various fields. Engineering design of such facilities requires accurate prediction of reactions on light nuclei in a wide incident energy range. Therefore, we have developed a physics-based computational code system dedicated for deuteron-induced reactions, called DEURACS. In fiscal year 2016, we calculated double-differential neutron yields from deuteron bombardment on thick Be and C targets, and the calculation reproduced the experimental data quantitatively well in the incident energy range up to 50 MeV. From the results, it has been found that DEURACS can accurately predict reactions on light nuclei in a wide incident energy range. In addition, component-by-component analysis has revealed that the nonelastic breakup reactions make the most dominant contribution to neutron production.

Summary of instructor training program in FY2014 aiming at Asian countries introducing nuclear technologies for peaceful use (Contract program)

Hidaka, Akihide; Nakano, Yoshihiro; Watanabe, Yoko; Arai, Nobuyoshi; Sawada, Makoto; Kanaizuka, Seiichi*; Katogi, Aki; Shimada, Mayuka*; Ishikawa, Tomomi*; Ebine, Masako*; et al.

JAEA-Review 2016-011, 208 Pages, 2016/07

JAEA-Review-2016-011-01.pdf:33.85MB
JAEA-Review-2016-011-02.pdf:27.68MB

JAEA has been conducting the Instructor Training Program (ITP) since 1996 under the auspices of MEXT to contribute to human resource development in currently 11 Asian countries in the field of radiation utilization for seeking peaceful use of nuclear energy. ITP consists of Instructor Training Course (ITC), Follow-up Training Course (FTC) and Nuclear Technology Seminars. In the ITP, trainings or seminars relating to technology for nuclear utilization are held in Japan by inviting nuclear related people from Asian countries to Japan and after that, the past trainees are supported during FTC by dispatching Japanese specialists to Asian countries. News Letter is also prepared to provide the broad range of information obtained through the trainings for local people near NPPs in Japan. The present report describes the activities of FY2014 ITP and future challenges for improving ITP more effectively.