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Takeuchi, Tomoaki; Ueno, Shunji; Komanome, Hirohisa*; Otsuka, Noriaki; Shibata, Hiroshi; Kimura, Nobuaki; Matsui, Yoshinori; Tsuchiya, Kunihiko; Araki, Masanori
Proceedings of 6th International Symposium on Material Testing Reactors (ISMTR-6) (Internet), 7 Pages, 2013/10
During the station blackout situation at the Fukushima Dai-ichi (1F) Nuclear Power Plant, conventional in-pile instrumentation systems did not work sufficiently, resulting in the progress of the severe accident. In June 2011, the Japanese government referred to "Enhancement of instrumentation to identify the status of the reactors and PCVs" as a lesson of the accident at the 1F NPP, in the report of Japanese government to the IAEA ministerial conference in accordance with such situation, we started from 2012 a research and development which corresponds to the provisions so as to monitor the NPPs situations during a severe accident. In this research and development, we have been building of technical bases of a radiation-resistant high-definition and high-sensitivity monitoring camera, a wireless transmission system, and radiation- and heat-resistant signal line. The objective and latest progress situations of the R&D including the results of the characteristic experiments will be introduced in this symposium.
Kakei, Sadanori*; Kimura, Akihiro; Niizeki, Tomotake*; Ishida, Takuya; Nishikata, Kaori; Kurosawa, Makoto; Yoshinaga, Hideo*; Hasegawa, Yoshio*; Tsuchiya, Kunihiko
Proceedings of 6th International Symposium on Material Testing Reactors (ISMTR-6) (Internet), 7 Pages, 2013/10
The Japan Materials Testing Reactor (JMTR) is expected to contribute to the expansion of industrial utilization, such as the domestic production of Mo for the medical diagnosis medicine Tc. Production by the (n, ) method is proposed as domestic Mo production in JMTR because of the low amount of radioactive wastes and the easy Mo/Tc production process. Molybdenum oxide (MoO) pellets, poly zirconium compounds (PZC) and poly titanium compounds (PTC) are used as the irradiation target and generator for the production of Mo/Tc by the (n, ) method. However, it is necessary to use the enriched MoO, which is very expensive, to increase the specific activity of Mo. Additionally, a large amount of used PZC and PTC is generated after the decay of Mo. Therefore, this recycling technology of used PZC/PTC has been developed to recover molybdenum (Mo) as an effective use of resources and a reduction of radioactive wastes. The total Mo recovery rate of this process was 95.8%. From the results of the hot experiments, we could demonstrate that the recovery of MoO and the recycling of PZC are possible. In the future, the equipment of recovering Mo will be installed in JMTR-Hot Cell, and this recycling process will be able to contribute to the reduction of production costs of Tc and the reduction of radioactive wastes.
Tsuchiya, Kunihiko; Nishikata, Kaori; Tanase, Masakazu*; Shiina, Takayuki*; Ota, Akio*; Kobayashi, Masaaki*; Yamamoto, Asaki*; Morikawa, Yasumasa*; Takeuchi, Nobuhiro*; Kaminaga, Masanori; et al.
Proceedings of 6th International Symposium on Material Testing Reactors (ISMTR-6) (Internet), 9 Pages, 2013/10
no abstracts in English
Dorn, C. K.*; Tsuchiya, Kunihiko; Takemoto, Noriyuki; Ito, Masayasu; Hori, Junichi*; Chekushina, L.*; Hatano, Yuji*; Chakrov, P.*; Kawamura, Hiroshi
Proceedings of 6th International Symposium on Material Testing Reactors (ISMTR-6) (Internet), 9 Pages, 2013/10
no abstracts in English
Kimura, Akihiro; Awaludin, R.*; Shiina, Takayuki*; Tanase, Masakazu*; Kawauchi, Yukimasa*; Gunawan, A. H.*; Lubis, H.*; Sriyono*; Ota, Akio*; Genka, Tsuguo; et al.
Proceedings of 6th International Symposium on Material Testing Reactors (ISMTR-6) (Internet), 7 Pages, 2013/10
JP, 2011-173260 Patent publication (In Japanese)This research is development of Tc production. Tc is generated by decay of Mo. The supply of Mo in Japan depends entirely on the import from foreign countries. Thus, it is needed to supply Mo stably by the domestic manufacturing. A practical production of Tc was tried by the method with 1 Ci of Mo produced in MPR-30. The results showed that the recovery yields were approximately 70%. The concentration of the product obtained was estimated to be corresponding to about 30 GBq (800 mCi)/ml when 150g of MoO was irradiated for 5 days in MPR-30. Impurity of Mo was less than 4.410%, which was lower than that of Japanese tentative regulation criteria. The radiochemical purity was higher than 99.8% that cleared the tentative regulation (95%) of Japan.
Ito, Masayasu; Taguchi, Taketoshi; Miyauchi, Masaru; Sozawa, Shizuo
no journal, ,
It has been 45 years since the first criticality of JMTR in March 1968, and unfortunately, two contaminated water leakages from the stainless steel pipes occurred in 2012. Results of the investigation showed that the cause of the leakages was cracks due to stress corrosion cracking (SCC) from the outer surface, and crevice corrosion from the inner surface, respectively. Although visual inspection for these pipes had been carried out as regular inspections before the leakages occurred, these cracks were invisible to the naked eye. Since the X-ray radiography can detect internal flaws/cracks, was investigated as a non-destructive inspection to assess the integrity of the aged liquid waste transfer pipes in the JMTR. In this presentation, observation results by the X-ray radiography and the X-ray CT will be reported, and the applicability of the X-ray radiography.