Integrating radiation protection criteria for radioactive waste management into remediation procedures in existing exposure situations after a nuclear accident

Sugiyama, Daisuke*; Kimura, Hideo; Tachikawa, Hirokazu*; Iimoto, Takeshi*; Kawata, Yosuke*; Ogino, Haruyuki*; Okoshi, Minoru*

Journal of Radiological Protection, 38(1), p.456 - 462, 2018/03

https://doi.org/10.1088/1361-6498/aaa155

Experience after the accident at the Fukushima Daiichi Nuclear Power Station has shown that there is a need to establish radiation protection criteria for radioactive waste management consistent with the criteria adopted for the remediation of existing exposure situations. A stepwise approach to setting such criteria is proposed. Initially, a reference level for annual effective dose from waste management activities in the range 1-10 mSv should be set, with the reference level being less than the reference level for ambient dose. Subsequently, the reference level for annual effective dose from waste management activities should be reduced in one or more steps to achieve a final target value of 1 mSv. The dose criteria at each stage should be determined with relevant stakeholder involvement. Illustrative case studies show how this stepwise approach might be applied in practice.

Concept of curved magnetically guided liquid lithium target without a back plate for IFMIF

Kimura, Haruyuki; Hoashi, Eiji*

Fusion Engineering and Design, 88(5), p.327 - 340, 2013/06

https://doi.org/10.1016/j.fusengdes.2013.03.029

Curved magnetically guided lithium target (MGLT) without a back plate was proposed for accelerator-based intense neutron source such as IFMIF. The curved MGLT can replace conventional lithium target with a curved back plate under the most severe condition on neutron irradiation. The magnetic field suited for MGLT is produced in combination of radiation-proof resistive coils and F82H parts (yokes, nozzles and high flux test module (HFTM)). Shape of the magnetic field becomes curved in the target region by setting HFTM closely to MGLT. Lithium flow on MGLT was analyzed in detail by two dimensional equations of motion with magnetic field calculated by the Poisson Superfish code. The necessary magnetic flux density at the target region was found to be about 0.5 T to fulfill the IFMIF target conditions; flow speed of 15 m/s, curvature radius of 1-1.6 m and flow thickness of 0.025 m. A narrow gap (a few mm) between MGLT and HFTM could be controlled via control of the coil current.

Overview of materials research and IFMIF-EVEDA under the Broader Approach framework

Nishitani, Takeo; Tanigawa, Hiroyasu; Yamanishi, Toshihiko; Clement Lorenzo, S.*; Baluc, N.*; Hayashi, Kimio; Nakajima, Noriyoshi*; Kimura, Haruyuki; Sugimoto, Masayoshi; Heidinger, R.*; et al.

Fusion Science and Technology, 62(1), p.210 - 218, 2012/07

https://doi.org/10.13182/FST12-A14137

Recent progress in the material related researches and the IFMIF/EVEDA project, which are carried out under the Broader Approach (BA) framework, is reported. In the International Fusion Energy Research Center (IFERC) project of BA, the R&D building was completed March 2010 at the Rokkasho BA site. R&Ds on reduced activation ferritic/ martensitic (RAFM) steels as structural material, SiC/SiC composites as a flow channel insert material and/or alternative structural material, advanced tritium breeders and neutron multipliers, and tritium technology relevant to the DEMO operational condition are progressed in Japan and EU. In the IFMIF/EVEDA project, the fabrication of the injector for the IFMIF prototype accelerator was completed at the CEA Saclay, and the first proton beam was obtained in May, 2011. The IFMIF lithium target test loop was completed in March 2011, and a lithium flow of 5 m/s was obtained.

IFMIF specifications from the users point of view

Garin, P.*; Diegele, E.*; Heidinger, R.*; Ibarra, A.*; Jitsukawa, Shiro; Kimura, Haruyuki; Mslang, A.*; Muroga, Takeo*; Nishitani, Takeo; Poitevin, Y.*; et al.

Fusion Engineering and Design, 86(6-8), p.611 - 614, 2011/10

https://doi.org/10.1016/j.fusengdes.2011.01.109

This paper summarizes the proposals and findings of the IFMIF Specification Working Group established to update the Users requirements and top level specifications for the Facility. Special attention is given to the different roadmaps of fusion path way towards power plants, of materials R&D and of facilities and their interactions. The materials development and validation activities on structural materials, blanket functional materials and non-metallic materials are analyzed and specific objectives and requirements to be implemented in IFMIF are proposed. Emphasis is made in additional potential validation activities that can be developed in IFMIF for ITER TBM qualification as well as for DEMO-oriented mock-up testing.

Engineering design and construction of IFMIF/EVEDA lithium test loop; Design and fabrication of integrated target assembly

Kondo, Hiroo; Furukawa, Tomohiro; Hirakawa, Yasushi; Nakamura, Hiroo*; Ida, Mizuho; Watanabe, Kazuyoshi; Miyashita, Makoto*; Horiike, Hiroshi*; Yamaoka, Nobuo*; Kanemura, Takuji; et al.

Proceedings of 23rd IAEA Fusion Energy Conference (FEC 2010) (CD-ROM), 8 Pages, 2010/10

http://www-naweb.iaea.org/napc/physics/FEC/FEC2010/html/node110.htm#24071

The Engineering Validation and Engineering Design Activity (EVEDA) for the International Fusion Materials Irradiation Facility (IFMIF) is proceeded as one of the ITER Broader Approach (BA) activities. The EVEDA Li test loop (ELTL) is aimed at validating stability of the Li target and feasibility of a Li purification system as the key issues. In this paper, the design of the ELTL especially of a target assembly in which the Li target is produced by the contraction nozzle is presented.

Values of construction of IFMIF accelerator prototype and targeted issues

Sugimoto, Masayoshi; Garin, P.*; Vermare, C.*; Shidara, Hiroyuki; Kimura, Haruyuki; Suzuki, Hiromitsu; Ohira, Shigeru; Okumura, Yoshikazu; Mosnier, A.*; Facco, A.*; et al.

Kasokuki, 7(2), p.110 - 118, 2010/07

http://ci.nii.ac.jp/naid/40017253050

International Fusion Materials Irradiation Facility (IFMIF) is an accelerator-based neutron irradiation facility dedicated for development of fusion materials. Engineering Validation and Engineering Design Activities (EVEDA) phase of IFMIF project has been initiated in June 2007 and a prototype of the IFMIF accelerator (40 MeV - 125 mA CW Deuteron) is under construction in Rokkasho, Aomori. The target of the prototype is 9 MeV - 125 mA CW beam operation, which is full scale prototyping up to the first tank of superconducting linac section. In this report, the major technical specifications and issues of this extremely high-power machine are overviewed and expected results through operation in future are summarized.

The Accelerator prototype of the IFMIF/EVEDA project

Mosnier, A.*; Beauvais, P. Y.*; Branas, B.*; Comunian, M.*; Facco, A.*; Garin, P.*; Gobin, R.*; Gournay, J. F.*; Heidinger, R.*; Ibarra, A.*; et al.

Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.588 - 590, 2010/05

http://accelconf.web.cern.ch/AccelConf/IPAC10/papers/mopec056.pdf

Status of JT-60SA tokamak under the EU-JA broader approach agreement

Matsukawa, Makoto; Kikuchi, Mitsuru; Fujii, Tsuneyuki; Fujita, Takaaki; Hayashi, Takao; Higashijima, Satoru; Hosogane, Nobuyuki; Ikeda, Yoshitaka; Ide, Shunsuke; Ishida, Shinichi; et al.

Fusion Engineering and Design, 83(7-9), p.795 - 803, 2008/12

https://doi.org/10.1016/j.fusengdes.2008.06.047

no abstracts in English

Ripple reduction with ferritic insert in JFT-2M

Shinohara, Koji; Sato, Masayasu; Kawashima, Hisato; Tsuzuki, Kazuhiro; Suzuki, Sadaaki; Urata, Kazuhiro*; Isei, Nobuaki; Tani, Takashi; Kikuchi, Kazuo; Shibata, Takatoshi; et al.

Fusion Science and Technology, 49(2), p.187 - 196, 2006/02

https://doi.org/10.13182/FST06-A1094

In JFT-2M, the toroidal field ripple was reduced by ferritic insert. Two kinds of ripple reduction were carried out. In the first case, ferritic steel was installed between toroidal field coil and vacuum vessel, just under toroidal field coil, outside vacuum vessel. In the second one, ferritic steel was installed inside vacuum vessel covering almost whole inside wall. The ripple was successfully reduced in the both cases. The temperature increment on the first wall measured by infrared TV was also reduced. A new version of OFMC code was also developed to analyze fast ion behavior in the complex structure of the toroidal field. The TF ripple reduction with ferritic insert in JFT-2M is summarized in this article.

Study of SOL/divertor plasmas in JFT-2M

Kawashima, Hisato; Sengoku, Seio; Uehara, Kazuya; Tamai, Hiroshi; Shoji, Teruaki*; Ogawa, Hiroaki; Shibata, Takatoshi; Yamamoto, Masahiro*; Miura, Yukitoshi; Kusama, Yoshinori; et al.

Fusion Science and Technology, 49(2), p.168 - 186, 2006/02

https://doi.org/10.13182/FST06-A1093

Experimental efforts on JFT-2M have been devoted to understand SOL/Divertor plasmas and to investigate power and particle controllability. Open divertor configuration was used for the first decade of JFT-2M started in 1984. We found out the SOL/Divertor plasma properties such as in/out asymmetry, heat and particle diffusivities, and SOL current at ELMs. Handling of power and particle was demonstrated by active control methods such as local pumping, edge ergodization, divertor biasing, and edge heating. For improvement of power and particle control capability of divertor, it was modified to closed configuration in 1995, which demonstrated the baffling effects with narrower divertor throat. Dense and cold divertor state (n = 410 m and T = 4 eV), compatible with the improved confinement modes (e.g. H-mode), was realized by strong gas puffing. Being related with the core confinement at H-mode, the edge plasma fluctuations were identified by an electrostatic probe. These are reviewed in this paper.