IAEA low enriched uranium bank; Towards the realization of international management initiatives

Tamai, Hiroshi; Tazaki, Makiko; Suda, Kazunori

Nihon Genshiryoku Gakkai-Shi ATOMO, 60(1), p.25 - 29, 2018/01

IAEA Low Enriched Uranium Bank, which is one of international management initiatives of nuclear materials operated by IAEA, will be realized soon. During increasing concern on proliferation risk of sensitive nuclear technologies as well as in this century the potential acquisition by terrorists, the IAEA bank will offer the fuel assurance aiming at decreasing incentive for acquiring those sensitive technologies. Throughout the argument on the criteria for the fuel supply, the bank site and its requirement have been established and will be in operation next year. The background, significance, and development of this initiative are described.

Requirements for pellet injection in ITER scenarios with enhanced particle confinement

Polevoi, A. R.*; Shimada, Michiya; Sugihara, Masayoshi; Igitkhanov, Y. L.*; Mukhovatov, V.*; Kukushkin, A. S.*; Medvedev, S. Y.*; Zvonkov, A. V.*; Ivanov, A. A.*

Nuclear Fusion, 45(11), p.1451 - 1456, 2005/11

https://doi.org/10.1088/0029-5515/45/11/028

Requirements for pellet injection parameters for plasma fuelling are assessed for ITER scenarios with enhanced particle confinement. A pellet injection throughput of 100 Pam/s would be sufficient. The assessment is based on the integrated transport simulations including models of pedestal transport, reduction of helium transport and boundary conditions compatible with SOL/divertor simulations. The requirements for pellet injection for the inductive H-mode scenario (HH98(y,2) = 1) are reconsidered taking account of a possible reduction of the particle loss obtained in some experiments at low collisionalities. The assessment of fuelling requirements is carried out for the hybrid and steady state scenarios with enhanced confinement with HH98(y,2) 1. A robustness of plasma performance to the variation of particle transport is demonstrated. A new type of steady state (SS) scenario is considered with neutral beam current drive (NBCD) and electron cyclotron current drive (ECCD) instead of lower hybrid current drive (LHCD).

Advance of research and development in the Japan Atomic Energy Research Institute

Okada, Sohei; Sawa, Kazuhiro

Denki Hyoron, 89(2), p.54 - 63, 2004/02

The Japan Atomic Energy Research Institute (JAERI) is comprehensively promoting Research and Development (R&D) activities to make the best use of a variety of potentials of atomic energy, based on the governmental policy described in the Atomic Energy Commission's "Long-Term Program for Research, Development and Utilization of Nuclear Energy" and the "Science and Technology Basic Plan" framed by the Council for Science and Technology Policy. These activities pursue long-range stable supply of energy, development of science and technology, and quality improvement of people's life in Japan. This paper introduces major advances of JAERI's R&D from December 2002 to November 2003.

Study on the thermal output scale of a very small reactor for district-heat-and-cooling system

Takahashi, Hiroki; Nakajima, Nobuya; Kusunoki, Tsuyoshi

JAERI-Tech 2003-052, 59 Pages, 2003/06

JAERI-Tech-2003-052.pdf:5.95MB

The feasibility study of a distributed small reactor system has been performed in JAERI for the utilization of the heat source for public welfare, especially for air-conditioning and hot water supply, from the view point of use expansion of nuclear energy. In this report, the optimization of heat supply system including the set up and analysis of the model city are studied for the prediction of short and long term heat demand in the heat supply area. It is important process for understanding the whole system image to estimate the suitable heat source scale for the heat demand of the heat supply area, which is within a 5-km radius from heat supply source. From the analysis, it is clear that two or more set of the nuclear reactors based on 100 MW thermal power are suitable. Furthermore, it is indicated that the introduced reactor system can be utilized for more than 30 year and the heat reserve system is indispensable. This results show the feasibility of a small reactor system for district heat-and cooling supply.

Neutronic study of a very small reactor MR-1G core for exclusive use of heat supply

Odano, Naoteru; Ishida, Toshihisa; Ochiai, Masaaki

JAERI-Research 2001-044, 53 Pages, 2001/10

JAERI-Research-2001-044.pdf:2.35MB

A very small reactor, MR-1G with a thermal output of 1 MW, is the integral-pressurized type reactor to be used for heat supply to an office building in a city. Neutronic study has been carried out for design of the MR-1G, the core of which could achieve continuous long-term operation without refueling for 10 years assuming a load factor of the core of 44 %. In the present study, arrangement of fuel rods and U enrichment of UO fuel rods were surveyed as design parameters. The U enrichment was determined to be 8.5 wt% to satisfy design requirement. Reactor physics parameters including reactivity coefficients and power distributions were evaluated for the determined core specifications. Reactor physics parameters related to core safety were also analyzed. Results of the safety analysis indicated that the determined core specifications satisfied design conditions. Reactor shutdown performance by dropping the reflector, which was adopted as a passive reactor shutdown system, was analyzed and confirmed it's availability from a viewpoint of reactor physics.

Theory and MHD simulation of fuelling by compact toroid injection

Suzuki, Yoshio; Hayashi, Takaya*; Kishimoto, Yasuaki

Nuclear Fusion, 41(7), p.873 - 881, 2001/07

https://doi.org/10.1088/0029-5515/41/7/308

no abstracts in English

Dynamics of spheromak-like compact toroids in a drift tube

Suzuki, Yoshio; Hayashi, Takaya*; Kishimoto, Yasuaki

Nuclear Fusion, 41(6), p.761 - 777, 2001/06

https://doi.org/10.1088/0029-5515/41/6/312

no abstracts in English

Design and manufacture of apparatus for analysis of atomic process on solid surfaces

Teraoka, Yuden; Yoshigoe, Akitaka

JAERI-Tech 2001-009, 41 Pages, 2001/03

JAERI-Tech-2001-009.pdf:1.99MB

no abstracts in English

Study on dissolution of UO to obtain the high U solution

; *; Sakurai, Koji*; ; Nomura, Kazunori; *

JNC TN8400 2000-032, 98 Pages, 2000/12

JNC-TN8400-2000-032.pdf:1.94MB

Concerning the preparation of high U solution for the crystallization process and the application of UO powder dissolution to that, the effects of final U concentration, dissolution temperature, nitric acid concentration and powder size on the dissolution of UO powder in the nitric acid where the final U concentration was 800g/L were investigated. The experimental results showed that the solubility of UO decreased with the increase of final UO concentration and powder size, and with the decrease of dissolution temperature and nitric acid concentration. It was also confirmed that in the condition where the final U concentration was sufficiently lower than the solubility of U, UO dissolution behavior in the high U solution could be estimated with the equation based on the fragmentation model which we had already reported. Based on these experimental results, the dissolution behavior of irradiated MOX fuel in high U solution was estimated and the possibility of supplying high U solution to the crystallization process was discussed. In the preparation of high U solution for the crystallization process, it was estimated that the present dissolution process (dissolution for fuel pieces of about 3cm long) needed a lot of time to obtain a high dissolution yield, but it was shorted drastically by the pulverization of fuel pieces. The burst of off-gas at the early in the dissolution of fuel powder seems to be avoidable with setting the appropriate dissolution condition, and it is important to optimize the dissolution condition with considering the capacity of off-gas treatment process.

Design study of a district-heating reactor installed in the basement of building

Kusunoki, Tsuyoshi; Odano, Naoteru; Nakajima, Nobuya; Fukuhara, Yoshifumi*; Ochiai, Masaaki

Nihon Genshiryoku Gakkai-Shi, 42(11), p.1195 - 1203, 2000/11

https://doi.org/10.3327/jaesj.42.1195

no abstracts in English