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Sakauchi, Hitoshi; Kikuchi, Yuki; Imaizumi, Haruki; Fukui, Yasutaka
Dekomisshoningu Giho, (57), p.34 - 42, 2018/03
OWTF (Oarai Waste Reduction Treatment Facility) is constructed for volume reduction processing and stabilization treatment of radioactive solid waste, which generate from hot facilities in Oarai Research and Development Center of Japan Atomic Energy Agency, using in-can type high frequency induction heating by remote control. In this report, we describe the outline of OWTF under construction and treatment technologies, in which incinerating and melting.
Sakauchi, Hitoshi; Sato, Isamu*; Donomae, Yasushi; Kitamura, Ryoichi
JAEA-Technology 2015-059, 352 Pages, 2016/03
JAEA-Technology-2015-059.pdf:51.53MB
OWTF (Oarai Waste Reduction Treatment Facility) is constructed for volume reduction processing and stabilization treatment of 
solid waste, which was generated from hot facilities in Oarai Research and Develop Center of Japan Atomic Energy Agency, using in-can type high frequency induction heating by remote control. This report describes corroborative tests, in which incinerating and melting performance for OWTF is confirmed with a full-scale testing furnace. We have been carrying out the tests of incinerating and melting treatment with some kinds of simulated wastes, such as enclosure form of radioactive wastes, material and articles.
Mimura, Hitoshi*; Yamagishi, Isao
Zeoraito, 31(4), p.115 - 124, 2014/12
Massive tsunami caused by the Great East Japan Earthquake attacked the Fukushima Daiichi Nuclear Power Plant and caused the nuclear accident of level 7 to overturn the safety myth of nuclear power generation. The domestic worst accident does not yet reach the convergence, and many inhabitants around the power plant are forced to double pains of earthquake disaster and nuclear accident. At present, large amounts of high-activity-level water over 500,000 tons are stored in Fukushima NPP-1 site, which is a serious obstacle to take measures for the nuclear accident. For the decontamination of high-activity-level water containing seawater, the circulating injection cooling system using packed columns with inorganic ion-exchangers is operated and the cold shutdown is accomplished. However, the advancement of operating system and the safety management of secondary solid wastes are very important subject. In this paper, the adsorption properties and solidification characteristics are compared for Cs and Sr selective adsorbents mainly composed of zeolites and the enhancement of adsorption properties are reported. Especially, naturally occurring zeolites abundant in Japan have high selectivity towards Cs, and also have excellent functions of gas trapping and self sintering for stable solidification. Zeolites are thus expected for the treatment and disposal of contaminated water in future. This paper also reports the present situation of safety management of solid wastes and the development of stable solidification methods, and summarizes the future subjects considering the safety disposal.
Nakano, Masahiro; Okawa, Hiroshi; Suzuki, Takeshi; Kishimoto, Katsumi; Terunuma, Akihiro; Yano, Masaaki
Dekomisshoningu Giho, (30), p.11 - 24, 2004/09
Japan Research Reactor No.2(JRR-2), heavy water moderated and cooled tank type research reactor with maximum thermal power of 10MW,was operated for over 36 years, and was permanently shut down in December, 1996. In 1997, decommissioning plan was submitted to the STA, and dismantling was begun. Decommissioning program of JRR-2 is divided into 4 phases. Phase 1, 2 had already been completely finished without any trouble. Furthermore, the phase 3 was also finished in February, 2004 as planned. On exposure of worker in phase 1, 2 and 3, it was achieved to control lower than the estimate. On exposure of worker in phase 1, 2 and 3, it was achieved to control lower than the estimate. Reactor will be removed in phase 4 by one piece removal technique. The reactor building is planned to use effectively as a hot experimental facilities after decommissioning. The decommissioning plan was changed that the reactor would be kept in safety storage.
Nakashio, Nobuyuki; Nakashima, Mikio; Hirabayashi, Takakuni*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 3(3), p.279 - 287, 2004/09
Large-scale melting tests of simulated miscellaneous solid wastes were conducted to characterize solidified products (50L-drum size). Two heating modes were adopted in the tests: hybrid heating and induction heating modes. In the former, wastes were heated with both an induction furnace and a plasma torch, and in the latter, an electrically-conductive crucible was used with the induction furnace. Visual observation, chemical analysis and radioactivity measurements were conducted to the solidified products. It was found that the radioisotope distribution of solidified products was almost homogeneous. There was no remarkable deterioration in the solidified products subsequent to the leaching test.
Hoshi, Akiko; Nakashio, Nobuyuki; Nakashima, Mikio
Genshiryoku Bakkuendo Kenkyu, 10(1-2), p.93 - 102, 2004/03
The Japan Atomic Energy Research Institute (JAERI) decided to adopt an advanced volume reduction program for low-level radioactive wastes. In this program, inorganic wastes are converted to stable glassy products suitable for disposal by a plasma melting system in the Waste Volume Reduction Facilities (WVRF). In this paper, plasma melting test of crucibles,ceramic filter elements,asbestos,and simulated fly ashes were carried out as a part of technical support for WVRF. The plasma melting treatment was applicable for crucibles and asbestos because homogeneous and glassy products were obtained by controlling of waste and loading condition. It was found that an oxidizing slag is needed for effective melting condition of ceramic filter elements with a plasma torch with inert gas, and controlling of slag components have the potential to stabilize volatile metals such as Zn, Pb in a solidified product in the melting test of simulated fly ash.
Nakashio, Nobuyuki; Nakashima, Mikio
Dekomisshoningu Giho, (26), p.45 - 55, 2002/11
Melting treatment of low-level radioactive wastes (LLW) is considered to be a promising technology for the preparation of a stable solid that will be disposed of in near surface repositories. This is because of large reduction of waste volume and production of a stable homogeneous solidified product. In the Japan Atomic Energy Research Institute (JAERI), the construction of the Waste Volume Reduction Facilities (WVRF) has been in progress since 1999. In advance of operation of the WVRF, we have been conducting melting tests of non-metallic solid wastes with the aim of establishing the optimum melting condition for preparation of a stable solid that is suitable for disposal. We have reviewed a part of the melting test conducted in our program.
Nakashima, Mikio; Fukui, Toshiki*; Nakashio, Nobuyuki; Isobe, Motoyasu*; Otake, Atsushi*; Wakui, Takuji*; Hirabayashi, Takakuni*
Journal of Nuclear Science and Technology, 39(6), p.687 - 694, 2002/06
Times Cited Count：16 Percentile：69.83(Nuclear Science & Technology)no abstracts in English
Fukui, Toshiki; Nakashio, Nobuyuki; Isobe, Motoyasu; Otake, Atsushi*; Wakui, Takuji*; Hirabayashi, Takakuni*; Nakashima, Mikio
JAERI-Review 2000-033, 82 Pages, 2001/02
JAERI-Review-2000-033.pdf:2.61MB
no abstracts in English
Isobe, Motoyasu; Kameo, Yutaka; Nakashio, Nobuyuki; Wakui, Takuji*; Iwata, Keiji*; Kibayashi, Tatsuyuki*; Kanazawa, Katsuo; Nakashima, Mikio; Hirabayashi, Takakuni*
JAERI-Tech 2000-049, 29 Pages, 2000/09
JAERI-Tech-2000-049.pdf:2.87MB
no abstracts in English
; ; *; *; *; *; *
JNC TN8440 2000-013, 179 Pages, 2000/04
JNC-TN8440-2000-013.pdf:10.31MB
The plutonium conversion development facility (PCDF) has been operated for 17 years and about 12 tons plutonium-uranium mixed oxide (MOX) powder has been converted since operation started in 1983. The first maintenance program for aging of apparatus was carried out from 1993 to 1994. The calcination-reduction fumace, liquid waste evaporator had been dismantled and renewed. The second maintenance program was carried out form 1998 to 1999. The microwave ovens, powder blender, ventilation control panel and so on were dismantled and renewed. Large volume radioactive wastes were generated during this maintenance such as the furnace, the filter casings and glove boxes. These wastes were too large to be packed into the waste container and these wastes were polluted by MOX powder unfixed on these surface. SO cutting and packing operation for these wastes and recovery of MOX powder from them were carried out. In this report, the method of this cutting and packing operation, the radioactive exposure to the operators in this operation, the estimation of nuclear material quantity migrated to filters, the evaluation of re-floating factor of radioactive material, etc. were discussed.
*; *
JNC TJ8420 2000-010, 171 Pages, 2000/03
JNC-TJ8420-2000-010.pdf:5.34MB
no abstracts in English
Maeda, Koichi; Ogasawara, Kensuke*; Nishizawa, Ichio
JAERI-Tech 2000-034, p.86 - 0, 2000/03
no abstracts in English
Fukui, Toshiki; Nakashio, Nobuyuki; Isobe, Motoyasu; Otake, Atsushi*; Wakui, Takuji*; Nakashima, Mikio; Hirabayashi, Takakuni*
Dai-7-Kai Doryoku Enerugi Gijutsu Shimpojiumu Koen Rombunshu (00-11), p.356 - 359, 2000/00
no abstracts in English
; ; Kato, Noriyoshi; Miyazaki, Hitoshi; Tanimoto, Kenichi
JNC TN9410 2000-002, 149 Pages, 1999/12
JNC-TN9410-2000-002.pdf:23.51MB
LEDF (Large Equipment Dismantling Facility) is the solid waste processing technology development facility that carries out high-volume reduction and low dosage processing. The high-volume reduction processing of the high dose -waste configured with combustible waste, pvc & rubber, spent ion exchange resin, and noncombustible waste have been planned the incinerating and melting facility using the in-can type high frequency induction heating in LEDF. This test is intended to clarify the design data. It was confirmed that the incinerating and melting performance, molten solid properties and exhaust gas processing performance with pilot testing equipment and bench scale equipment. The result of this test are as follows. (1)Processing speed is 6.7kg/h for the combustible waste, 13.0kg/h for the ion exchange resin, and 30.0kg/h for the noncombustible waste. For above optimum processing conditions are as follows. (a)Operating temperature is 1000
C for the combustible waste, 1300C for the ion exchange resin, 1500C for the noncombustible waste. (b)Air flow is 90Nm
/h. Air temperature is 300C. Air velocity is 20m/s. (2)Incineration time per day is 5h. Warm-up time and incineration time from the stop of waste charging is 0.5h. Melting time per day is 5h inconsideration of heating hold time of incinerated ash and melting of quartz. Warm-up time is 0.5h. (3)The system decontamination factor in Co, Cs and Ce with pilot testing equipment is 10
or more. (4)Design data of the iron doped silica gel judged to be have a applicability as RuO
gas absorber is as follows. (a)Its diameter distribute in the range of 0.8-1.7mm. (b)To have a decontamination factor of 10 can achieve for retention time of 3 seconds and its life time is about 1 year. (5)In terms of the distribution of the nuclear species in molten solid is evenly distributed. It was also confirmed that the distribution of main elements in ceramic layer is ...
;
JAERI-Tech 99-045, 141 Pages, 1999/06
no abstracts in English
Hashizume, Shuji; ; Matsumoto, Junko; Bamba, Tsunetaka
Genshiryoku Bakkuendo Kenkyu, 5(1), p.37 - 44, 1998/08
no abstracts in English
Hashizume, Shuji; Matsumoto, Junko; Bamba, Tsunetaka
JAERI-Review 96-013, 25 Pages, 1996/10
JAERI-Review-96-013.pdf:1.06MB
no abstracts in English
