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Fukaya, Yuji; Goto, Minoru; Shibata, Taiju
IAEA-TECDOC-2040, p.133 - 136, 2023/12
Japan has developed back-end technologies to establish a multi-recycling fuel cycle with fast breeder reactors (FBRs) to ensure energy resources. Even though the development of FBR has been retreated to one of fundamental research, the reprocessing technologies for uranium fuel and disposal technologies had been completed for Light Water Reactor (LWR) fuel cycle on the process. These technologies were inherited to utilities and are about to be practical. Now, Japan had been completed High Temperature Engineering Test Reactor (HTTR) a prototype and research reactor, a commercial High Temperature Gas-cooled Reactor (HTGR) design Gas Turbine High Temperature Reactor 300 (GTHTR300) with related reprocessing technologies, and is planning domestic demonstration reactor project. In this context, a representative fuel cycle policy is reprocessing in Japan. However, Japan has investigated various fuel cycle scenarios to expand the usage of the commercial HTGR. Then, we would like to introduce the scenarios and development status of related technologies in the present study.
Sakamoto, Yoshiaki
Genshiryoku Bakkuendo Kenkyu (CD-ROM), 30(1), p.15 - 18, 2023/06
The entire process of nuclear power generation is called the nuclear fuel cycle, and each process generates various types of radioactive waste. These radioactive wastes are generated from the operation and decommissioning of these facilities, and are treated and disposed of appropriately according to their radioactivity concentrations and properties. This paper describes the basic outline of the nuclear fuel cycle and the fundamentals of the treatment and disposal of radioactive waste (including radioactive waste from the use of radioactive materials in facilities other than the nuclear fuel cycle), called the back end of the nuclear fuel cycle.
Uchino, Seiko*; Narita, Hirokazu*; Kita, Keisuke*; Suzuki, Hideya*; Matsumura, Tatsuro; Naganawa, Hirochika*; Sakaguchi, Koichi*; Oto, Keisuke*
Solvent Extraction Research and Development, Japan, 30(1), p.39 - 46, 2023/00
The extraction of trivalent rare earth ions (RE) from HNO solution using a triamide amine, tris(N,N-di-2-ethylhexyl-ethylamide)amine (DEHTAA), was conducted, and the extraction mechanism was estimated from extraction behavior of HNO and RE and the relationship between atomic number and extraction percentages (E%) for RE. A DEHTAA molecule dominantly formed a DEHTAA HNO at 1.0 M HNO and a DEHTAA(HNO) at 6.0 M HNO in the acid-equilibrated organic phase. This would provide the unique dependence of E% for the light RE on the HNO concentration, in which the E% value had a minimum and maximum at 0.5 M and 2 M HNO, respectively. The results of the slope analyses for the distribution ratios for RE suggested that the dominant RE complex was RE(NO)DEHTAA(DEHTAA HNO) at 1.0 M HNO. The E% for RE decreased from La to Lu at 1.0 M HNO; on the other hand, those increased from La to Nd at 0.25 M and from La to Sm and 6.0 M HNO.
Ohshima, Hiroyuki; Morishita, Masaki*; Aizawa, Kosuke; Ando, Masanori; Ashida, Takashi; Chikazawa, Yoshitaka; Doda, Norihiro; Enuma, Yasuhiro; Ezure, Toshiki; Fukano, Yoshitaka; et al.
Sodium-cooled Fast Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.3, 631 Pages, 2022/07
This book is a collection of the past experience of design, construction, and operation of two reactors, the latest knowledge and technology for SFR designs, and the future prospects of SFR development in Japan. It is intended to provide the perspective and the relevant knowledge to enable readers to become more familiar with SFR technology.
Okamura, Tomohiro*; Nishihara, Kenji; Katano, Ryota; Oizumi, Akito; Nakase, Masahiko*; Asano, Hidekazu*; Takeshita, Kenji*
JAEA-Data/Code 2021-016, 43 Pages, 2022/03
The quantitative prediction and analysis of the future nuclear energy utilization scenarios are required in order to establish the advanced nuclear fuel cycle. However, the nuclear fuel cycle consists of various processes from front- to back-end, and it is difficult to analyze the scenarios due to the complexity of modeling and the variety of scenarios. Japan Atomic Energy Agency and Tokyo Institute of Technology have jointly developed the NMB code as a tool for integrated analysis of mass balance from natural uranium needs to radionuclide migration of geological disposal. This user manual describes how to create a database and scenario input for the NMB version 4.0.
Sagayama, Yutaka; Sawada, Tetsuo*; Tanaka, Harukuni*
Enerugi Foramu, (807), p.18 - 22, 2022/03
Discussing the necessity of the nuclear fuel cycle, its future, and issues (costs, pros and cons of the LWR cycle, etc.). The trend toward carbon neutrality will lead to a rush to build nuclear (light water reactor) power plants in many countries. As a result, the price of natural uranium is expected to skyrocket, increasing the need for fast reactor cycle development. It is essential to present to the world the concept of commercialization of fast reactors that combine high safety and economic efficiency, and to proceed with development steadily in order to realize it promptly, without dissipating the technologies for design, construction, operation, and maintenance of fast reactors that Japanese industry and JAEA have accumulated through the development of MONJU and other projects.
Yoshinaka, Kazuyuki; Suzuki, Masafumi*
Gijutsushi, (659), p.4 - 7, 2021/11
The regulatory standards for nuclear facilities were revised, reflecting the lessons learned from Fukushima-Daiichi NPS accident. Many requirements for safety measures, in case there are natural disaster or severe accidents, are added for nuclear fuel cycle facilities. Aiming achievement of the nuclear fuel cycle, various safety measures for conforming to new regulatory standard and improving, have been taken at Rokkasho reprocessing plant.
Tamai, Hiroshi; Mochiji, Toshiro; Senzaki, Masao*; Iwamoto, Tomonori*; Ishiguro, Yuzuru*; Kitade, Yuta; Sato, Heigo*; Suehiro, Rie*; Taniguchi, Tomihiro*; Fukasawa, Tetsuo*; et al.
Dai-41-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2020/11
In light of recent delay of plutonium use in Japan and the increasing criticism of nuclear non-proliferation and nuclear security in the nuclear fuel cycle, the validity of these criticisms will be examined for the sustainable development of the nuclear fuel cycle policy. Issues on the view point of nuclear non-proliferation and nuclear security are examined.
Fukasawa, Tetsuo*; Hoshino, Kuniyoshi*; Yamashita, Junichi*; Takano, Masahide
Journal of Nuclear Science and Technology, 57(11), p.1215 - 1222, 2020/11
Times Cited Count:1 Percentile:12.16(Nuclear Science & Technology)The flexible fuel cycle initiative system (FFCI system) has been developed to reduce spent fuel (SF) amounts, to keep high availability factor for the reprocessing plant and to increase the proliferation resistance for the recovered Pu. The system separates most U from the SF at first, and the residual material called recycle material (RM) which contains Pu, minor actinides, fission products and remaining U will go to Pu(+U) recovery from the RM for Pu utilizing reactor in future. The Pu utilizing reactor is FBR or LWR with MOX fuel. The RM is the buffer material between SF reprocessing and Pu utilizing reactor with compact size and high proliferation resistance, which can suppress the amount of relatively pure Pu. The innovative technologies of FFCI are most U separation and temporary RM storage. They are investigated by the literature survey, fundamental experiments using simulated material and analyses using simulation code. This paper summarizes the feasibility confirmation results of FFCI.
Mochiji, Toshiro; Senzaki, Masao*; Tamai, Hiroshi; Iwamoto, Tomonori*; Ishiguro, Yuzuru*; Kitade, Yuta; Sato, Heigo*; Suehiro, Rie*; Taniguchi, Tomihiro*; Fukasawa, Tetsuo*; et al.
Enerugi Rebyu, 40(8), p.56 - 57, 2020/07
Strict application of IAEA safeguards and nuclear security should be implemented for Japan's full-scale nuclear fuel cycle. Based on the knowledge and experience of research and development in the nuclear fuel cycle, nuclear material management, the effective and efficient promotion of new technologies should be promoted with scientific and demonstrative measures to strengthen the world's nuclear non-proliferation and nuclear security. Development or sophistication of new technologies, human resource development, and reinforcement of the international framework are future challenge in the international community.
Mochiji, Toshiro; Senzaki, Masao*; Tamai, Hiroshi; Iwamoto, Tomonori*; Ishiguro, Yuzuru*; Kitade, Yuta; Sato, Heigo*; Suehiro, Rie*; Taniguchi, Tomihiro*; Fukasawa, Tetsuo*; et al.
Enerugi Rebyu, 40(7), p.58 - 59, 2020/06
Japan have promoted the peaceful use of plutonium with the nuclear non-proliferation commitment based on IAEA safeguards agreement and Japan-US nuclear cooperation agreement, as well as ensuring transparency of the policy that Japan has no plutonium without purpose of use. In promoting the nuclear fuel cycle, adherence to those measures and maintaining plutonium utilization by means of plutonium-thermal, and a fast reactor cycle to achieve large-scale and long-term energy supply and environmental improvement, therefore, further research and development is essential.
Mochiji, Toshiro; Senzaki, Masao*; Tamai, Hiroshi; Iwamoto, Tomonori*; Ishiguro, Yuzuru*; Kitade, Yuta; Sato, Heigo*; Suehiro, Rie*; Taniguchi, Tomihiro*; Fukasawa, Tetsuo*; et al.
Enerugi Rebyu, 40(6), p.58 - 59, 2020/05
In order to promote the peaceful use of nuclear energy, it is important not only to ensure safety but also to ensure nuclear non-proliferation and nuclear security. Japan has contributed to the international community through strengthening nuclear non-proliferation and nuclear security capabilities with technical and human resource development. However, in the wake of the accident at the Fukushima Daiichi Nuclear Power Plant in 2011, Japan's nuclear power plants have not restarted or plutonium use has not progressed smoothly. Concerns have been shown. Towards appropriate steps of Japan's nuclear fuel cycle policy, such concerns are examined and future efforts are summarized.
Hayafune, Hiroki; Maeda, Seiichiro; Ohshima, Hiroyuki
Nihon Genshiryoku Gakkai-Shi ATOMO, 61(11), p.798 - 803, 2019/11
In the "Strategic Roadmap" of Fast Reactor Development decided at the Inter-Ministerial Council for Nuclear Power in December 2018, the development works for the around next 10 years were identified, and the role of JAEA was presented. In response, JAEA has prepared a framework for R&D plans for about 5 years on the fast reactor technology and the fuel cycle technology (reprocessing, fuel manufacturing, fuel and material development). In the future, JAEA will promote independent R&D works based on these plans, and provide the obtained R&D results together with various testing functions of JAEA to the activities of the private sector, etc. Through these actions, JAEA will actively contribute to the future fast reactor development. This article outlines JAEA's policy and the R&D items (development of ARKADIA; Advanced Reactor Knowledge- and AI-Aided Design Integration Approach through the whole Plant Life Cycle, development of standards and standards system, development of safety improvement technology, research in the fuel cycle technology), the policy of international cooperation, the human resource development, and the future perspective were explained.
Baron, P.*; Cornet, S. M.*; Collins, E. D.*; DeAngelis, G.*; Del Cul, G.*; Fedorov, Y.*; Glatz, J. P.*; Ignatiev, V.*; Inoue, Tadashi*; Khaperskaya, A.*; et al.
Progress in Nuclear Energy, 117, p.103091_1 - 103091_24, 2019/11
Times Cited Count:73 Percentile:94.03(Nuclear Science & Technology)The results of an international review of separation processes for spent nuclear fuel (SNF) recycling in future closed fuel cycles with the evaluation of Technology Readiness Level are reported. This study was made by the Expert Group on Fuel Recycling Chemistry (EGFRC) organised by the Nuclear Energy Agency (NEA) of the Organisation for Economic Co-operation and Development (OECD). A unique feature of this study was that processes were classified according to a hierarchy of separations aimed at different elements within spent fuel (uranium; uranium-plutonium co-recovery; minor actinides; high heat generating radionuclides) and also the Head-end processes, used to prepare the SNF for chemical separation, were included. Separation processes covered both wet (hydrometallurgical) and dry (pyro-chemical) processes.
Takano, Masahide
Wagakuni Shorai Sedai No Enerugi O Ninau Kakunenryo Saikuru; Datsu Tanso Shakai No Enerugi Anzen Hosho; NSA/Commentaries, No.24, p.163 - 167, 2019/03
This article summarizes R&D status of the nitride fuel cycle for minor actinides (MA) transmutation. Status of nitride fuel fabrication, material properties and fuel performance code, pyrochemical reprocessing, and nitrogen-15 enrichment are described.
Fujita, Shunya*; Abe, Yutaka*; Kaneko, Akiko*; Yuasa, Tomohisa*; Segawa, Tomoomi; Yamada, Yoshikazu; Kato, Yoshiyuki; Ishii, Katsunori
Proceedings of 26th International Conference on Nuclear Engineering (ICONE-26) (Internet), 8 Pages, 2018/07
Mixed uranium oxide and plutonium oxide powder is produced from uranyl nitrate and plutonium nitrate mixed solution by the microwave heating denitration method in the spent fuel reprocessing process. Since the microwave heating method is accompanied by a boiling phenomenon, it is necessary to fully grasp the operating conditions in order to avoid flashing and spilling in the mass production of denitrification technology for the future. In this research, it was confirmed that a potassium chloride aqueous solution as a simulant of uranyl nitrate aqueous solution with high dielectric loss cause loss of microwave at the solution surface as the dielectric loss increased with the increase of KCl concentration by experimental and electromagnetic field analysis, and revealed that the change in the heating condition affects the generation of flushing.
Suda, Kazunori; Shimizu, Ryo; Tazaki, Makiko; Tamai, Hiroshi; Kitade, Yuta
Nihon Kaku Busshitsu Kanri Gakkai Dai-38-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2018/04
Since India's nuclear explosion in 1974, there has been continued discussion on nuclear non-proliferation. At first, to prevent proliferation of nuclear weapons, the International Nuclear Fuel Cycle Evaluation (INFCE) was established to discuss reprocessing, plutonium handling, and so on. After that, to respond to the threat of proliferation posed by DPRK, the international community desired to further enhance nuclear non-proliferation by strengthening the IAEA safeguards system. In recent years, some researchers at universities and national laboratories are studying proliferation resistance from the standpoint of nuclear materials that may be inherently self-protecting. This paper discusses minimization of proliferation risk and future prospects based on alternative measures for reprocessing, plutonium handling, and recycling described in INFCE-WG4.
Tsujimoto, Kazufumi; Arai, Yasuo; Minato, Kazuo
Nihon Genshiryoku Gakkai-Shi ATOMO, 59(11), p.644 - 648, 2017/11
no abstracts in English
Fujita, Shunya*; Abe, Yutaka*; Kaneko, Akiko*; Chonan, Fuminori*; Yuasa, Tomohisa*; Yamaki, Tatsunori*; Segawa, Tomoomi; Yamada, Yoshikazu
Proceedings of 25th International Conference on Nuclear Engineering (ICONE-25) (CD-ROM), 8 Pages, 2017/07
From the observation results, in the process of flushing, the behaviors leading to flushing were classified divided into three types. First type is that first generation bubble from heating leads to flushing. Second type is that nucleate boiling continues during heating and stop, finally single bubble generates and leads to flushing. Third type is defined that gradual evaporation occurs without bubbles. It was revealed that the total quantities of heat released by flushing are approximately equal when assuming the flushing mechanism, it can be triggered that a large amount of micro bubbles are instantaneously generated and grew.
Tamai, Hiroshi; Okubo, Ayako; Kimura, Yoshiki; Shinohara, Nobuo; Tazaki, Makiko; Shimizu, Ryo; Suda, Kazunori; Tomikawa, Hirofumi
Proceedings of INMM 58th Annual Meeting (Internet), 6 Pages, 2017/07
Nuclear forensics is a technical measure to analyse and collate samples of illegally used nuclear materials, etc., to clarify their origins, routes, etc. and contribute to criminal identifications. Close collaboration with police and judicial organizations is essential. The national response framework is being built up with international cooperation. Discussions on promoting technical capability and regional cooperation are presented.