Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Mimura, Ryuji; Muraguchi, Yoshinori; Nakashio, Nobuyuki; Nemoto, Koichi; Shiraishi, Kunio
Proceedings of 23rd International Conference on Nuclear Engineering (ICONE-23) (DVD-ROM), 5 Pages, 2015/05
The JAERI's Reprocessing Test Facility (JRTF) was the first engineering-scale reprocessing facility constructed in Japan. The JRTF was operated from 1968 to 1969 to reprocess spent fuels from the Japan Research Reactor No.3 (JRR-3). As a result of the operation (total 3 runs) by PUREX process, 200 g of highly purified plutonium (Pu) were extracted. In this operation, about 70 m of liquid waste was generated and part of this waste, which including Pu, with relatively high radioactivity, was stored in six large tanks. After shutdown of the facility, the JRTF decommissioning program was started in 1990 to develop decommissioning technologies and to obtain experiences and data on dismantling of fuel cycle facilities. Liquid waste in the tanks was treated from 1982 to 1998. Dismantling of tanks started in 2002. The tanks were installed in narrow concrete cells and inside of the cell was high dose area. Dismantling method for the tank is important factor to decide manpower and time for dismantlement. In this paper, in-situ dismantling of the liquid waste storage tank and its preparation work are discussed.
Mizukoshi, Seiji; Oshima, Soichiro; Shimada, Taro
JAERI-Tech 2005-011, 122 Pages, 2005/03
The radiological and physical characteristic on decommissioning, such as component and structure weights and radioactivity of the 1.1 MWe class reference nuclear power plants summarized in the NUREG reports of the US NRC were classified,arranged and compared with the domestic commercial nuclear power plants and JPDR from a view point of dismantling plan and waste management for decommissioning. As the results, it was found that the radioactive component and structure weights was about 28,000ton、and non-radioactive structure weights was about 124,000ton less than the domestic commercial BWR. And it was found that this differences has mainly influenced dismantling costs for decommissioning. Farther, it was found that the concrete element composition rates of B, Ni, Nb and so were differerence of one or more figures btween the reference nuclear power plants and the domestic commercial PWR or JPDR.Also,it was found that the this difference became about two or three times by radioactivity concentration and has mainly influenced transport and disposal costs for decommissioning.
Akutsu, Atsushi; Kishimoto, Katsumi; Sukegawa, Takenori; Shimada, Taro
JAERI-Tech 2003-090, 75 Pages, 2004/01
The Japan Research Reactor No.1 (JRR-1) that was constructed first in Japan was permanently shut down after operation from 1957 to 1968. At present, the reactor part is in safe store conditions. The JRR-1 facility is being used as an exhibition room for the time being, and will be dismantled in the future. In consideration of future dismantling of the facility, the radioactive inventory in reactor part was calculated using computer codes that are Two-Dimensional Discrete Ordinates Transport Code (DORT) and Oak Ridge Isotope Generation and Depletion Code (ORIGEN-MD). The average concentration of radioactivity is estimated to be 6.40 Bq/g in the core tank as of April, 2002. It is also expected that the low level waste (LLW) weights approximately 400kg and very low level waste (VLLW) weights approximately 14,000kg, and the waste which doesn't need to deal as a radioactive material weights approximately 250,000kg.
Yanagihara, Satoshi; Tachibana, Mitsuo; Miyajima, Kazutoshi
Proceedings of International Conference; Decommissioning Challenges (CD-ROM), 8 Pages, 2003/00
Several decommissioning projects are on going and studies on decommissioning issues are in progress in JAERI. The JPDR and JRTF decommissioning projects have been set up as demonstration programs for future decommissioning large nuclear facilities. Therefore, efforts have been made not only to dismantle the facilities but also to collect data and lessons learnt on dismantling activities. The data and lessons learnt have been analyzed to produce the database for future decommissioning projects by categorizing into manpower expenditure, radiation dose and waste generation in project data, and safety aspect, waste management, work efficiency considerations in lessons learnt. respectively. The feedback experience has been effectively contributed to various areas on decommissioning such as studies on regulatory systems and planning of other dismantling projects. This paper deals with decommissioning experience and lessons learned in JAERI.
Nakamura, Hisashi; Nakashima, Mikio
JAERI-Tech 2002-006, 58 Pages, 2002/03
Radiation exposure was estimated on production and utilization of recycled items using dismantling waste by assuming that their usage are restricted to nuclear facilities. The radiation exposure attributed to production of a steel-plate cast iron waste container, a receptacle for slag, and a drum reinforcement was calculated to be in the range of several Sv to several tens of
Sv even in recycling contaminated metal waste of which radioactivity concentration of Co-60 is higher than the clearance level by a factor of two figures. It is also elucidated that casting of a multiple casting waste package meets the standards of dose equivalent rate for the transport of a radioactive package and the weight of the package will be able to kept around 20 tons for the convenience of the handling, in case of disposal of metal waste less than 37MBq/g with the steel-plate cast iron waste container. As the results, from the radiological exposure's point of view, it should be possible to use slightly contaminated metal for recycled items in waste management.
Yanagihara, Satoshi; Oshima, Soichiro; Sukegawa, Takenori; Tanabe, Norio*; Takaya, Junichi*; Kiuchi, Yoshio*; Yokota, Shuichi*
Nihon Genshiryoku Gakkai-Shi, 43(5), p.493 - 502, 2001/05
Times Cited Count:1 Percentile:11.82(Nuclear Science & Technology)no abstracts in English
Shiraishi, Kunio; Sukegawa, Takenori; Yanagihara, Satoshi
JAERI-Data/Code 99-050, p.113 - 0, 2000/01
no abstracts in English
Tachibana, Mitsuo; Hatakeyama, Mutsuo; Yanagihara, Satoshi
Nihon Genshiryoku Gakkai-Shi, 41(6), p.677 - 685, 1999/00
Times Cited Count:0 Percentile:0.00(Nuclear Science & Technology)no abstracts in English
; Sukegawa, Takenori; Yanagihara, Satoshi
JAERI-Data/Code 98-010, 186 Pages, 1998/03
no abstracts in English
Tanaka, Mitsugu
Proc. of Int. Conf. of Dismantling of Nuclear Facilities, 1, p.54 - 64, 1998/00
no abstracts in English
Yanagihara, Satoshi
Proc. of Int. Conf. of Dismantling of Nuclear Facilities, 1, p.179 - 190, 1998/00
no abstracts in English
Yanagihara, Satoshi
Nihon Kikai Gakkai-Shi, 100(948), p.1174 - 1178, 1997/11
no abstracts in English
Yanagihara, Satoshi; ; Sukegawa, Takenori; Tachibana, Mitsuo
Proc. of 5th Int. Conf. on Nucl. Eng. (ICONE-5)(CD-ROM), 6 Pages, 1997/00
no abstracts in English
Yanagihara, Satoshi; Tachibana, Mitsuo; ;
Proc., The 1994 Int. Symp. on Decontamination & Decommissioning, 0, 6 Pages, 1994/00
no abstracts in English
Yanagihara, Satoshi; ;
Proc. of the 1993 Int. Conf. on Nuclear Waste Management and Environmental Remediation,Vol. 3, p.423 - 431, 1993/00
no abstracts in English
; Ikezoe, Yasumasa; Shimizu, Saburo; Nakajima, Hayato; ; ; ; ;
JAERI-M 82-081, 65 Pages, 1982/07
no abstracts in English