Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 42

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Frontline of R&D for decommissioning and waste disposal, 1; R&D for processing and disposal of low-level radioactive waste and closure of uranium mine

Tsuji, Tomoyuki; Sugitsue, Noritake; Sato, Fuminori; Matsushima, Ryotatsu; Kataoka, Shoji; Okada, Shota; Sasaki, Toshiki; Inoue, Junya

Nihon Genshiryoku Gakkai-Shi ATOMO$$Sigma$$, 62(11), p.658 - 663, 2020/11

no abstracts in English

Journal Articles

Development of U and Pu co-processing process; Demonstration of U, Pu and Np Co-recovery with centrifugal contactors

Kudo, Atsunari; Kurabayashi, Kazuaki; Yanagibashi, Futoshi; Sasaki, Shunichi; Sato, Takehiko; Fujimoto, Ikuo; Obu, Tomoyuki

Proceedings of 2017 International Congress on Advances in Nuclear Power Plants (ICAPP 2017) (CD-ROM), 6 Pages, 2017/04

The Co-processing process is the extraction process to recover Pu/U mixed product solution with given Pu/U ratio for improving of nuclear proliferation resistance. In addition, Np is also recovered with U and Pu because Np is one of minor actinides and a long-lived radionuclide and Np has the extractability into TBP solvent. Development of its flowsheet achieves to decrease environmental effect of waste materials. The orientation of development about Co-processing process is to demonstrate of reprocessing the future spent fuels from a LWR, a LWR-MOX hybrid, and a FR-MOX with one cycle. We demonstrated by use of miniature reflux-type centrifugal contactors at the partitioning unit. The test conditions of the Pu/U ratio in the loaded solvents were 1%, 3%, and 5% considering the composition of spent fuels. We used the HAN as the reductant of Np (VI) for back extraction. The results of these tests were very good. We got the prospect of U, Pu, and Np Co-processing flowsheet.

Journal Articles

Fabrication of polymer optical waveguides for the 1.5-$$mu$$m band using focused proton beam

Miura, Kenta*; Machida, Yuki*; Uehara, Masato*; Kiryu, Hiromu*; Ozawa, Yusuke*; Sasaki, Tomoyuki*; Hanaizumi, Osamu*; Sato, Takahiro; Ishii, Yasuyuki; Koka, Masashi; et al.

Key Engineering Materials, 497, p.147 - 150, 2012/00

 Times Cited Count:7 Percentile:96.61

Journal Articles

Fabrication of polymer optical waveguides for the 1.5-$$mu$$m band using focused proton beam

Miura, Kenta*; Machida, Yuki*; Uehara, Masato*; Kiryu, Hiromu*; Ozawa, Yusuke*; Sasaki, Tomoyuki*; Hanaizumi, Osamu*; Sato, Takahiro; Ishii, Yasuyuki; Koka, Masashi; et al.

Key Engineering Materials, 497, p.147 - 150, 2011/12

 Times Cited Count:6 Percentile:2.48

Journal Articles

Performance of steam reforming technology in a long term treatment of waste TBP/dodecane

Nakagawa, Akinori; Sone, Tomoyuki; Sasaki, Toshiki; Nakazawa, Osamu; Tashiro, Kiyoshi

Proceedings of International Waste Management Symposia 2011 (WM 2011) (CD-ROM), 7 Pages, 2011/03

JAEA Reports

Treatment technology development of uranium contaminated spent TBP/n-dodecane solvent by steam reforming

Nakagawa, Akinori; Sone, Tomoyuki; Sasaki, Toshiki; Nakazawa, Osamu; Tashiro, Kiyoshi

JAEA-Technology 2010-014, 46 Pages, 2010/06

JAEA-Technology-2010-014.pdf:1.76MB

Steam reforming treatment system was developed for volume reduction of Tri-n-butyl phosphate contaminated with uranium, which is difficult to treat with incineration, due to generation of corrosive compounds, a large amount of secondary waste, etc. This system consists of a steam reforming process in which organic waste is decomposed/gasified in steam atmosphere and a submerged combustion process in which vaporized waste is burned in water and has good features such as high volume reduction rate of waste, low secondary waste generation rate, etc. Results obtained this study were as follows: Volume reduction rate of waste was 99.6%. Uranium entrainment to off-gas was suppressed and the concentration of uranium in waste water was under 0.037mg/L. The concentration of CO and NOx in the off-gas were less than 100ppm and 250ppm respectively. Plugging and corrosion control technologies were developed and it was confirmed that the waste treatment system can run for long periods.

JAEA Reports

Study of "Likely Scenarios" and "Less-likely Scenarios" for sub-surface disposal of radioactive waste

Sugaya, Toshikatsu; Sone, Tomoyuki; Nakatani, Takayoshi; Ishitoya, Kimihide; Funabashi, Hideyuki; Sasaki, Ryoichi*; Shimoda, Satoko*; Kurosawa, Mitsuru*

JAEA-Research 2009-063, 80 Pages, 2010/03

JAEA-Research-2009-063.pdf:8.35MB

The purpose of this study was to assess exposure dose of "Likely Scenarios" and "Less-likely Scenarios" on sub-surface disposal. They were two of "Classification of three types scenarios" in "Basic Policy for Safety Regulation Concerning Land Disposal of Low-Level Radioactive Waste (Interim Report)" formulated by the Nuclear Safety Commission of Japan. Selection of the assessed scenarios, development of the assessment tool and preliminary exposure dose assessment were conducted. Maximum exposure doses for "Likely Scenarios" and "Less-likely Scenarios" were less than each standard dose value in the Interim Report (Likely Scenarios: 10$$mu$$Sv/y, Less-likely Scenarios: 300$$mu$$Sv/y).

JAEA Reports

Long term treatment of waste TBP/n-dodecane with steam reforming system

Sone, Tomoyuki; Nakagawa, Akinori; Koyama, Hayato; Gunji, Kiyoshi; Nonaka, Kazuharu; Sasaki, Toshiki; Tashiro, Kiyoshi; Yamashita, Toshiyuki

JAEA-Technology 2009-023, 33 Pages, 2009/06

JAEA-Technology-2009-023.pdf:8.11MB

Steam reforming (SR) method consists of the gasification process in which organics are vaporized and decomposed with superheated steam and the oxidation process in which vaporized organics are decomposed by oxidizing reaction with heated air. 2,500L of waste TBP/n-dodecane contaminated with uranium was treated using the demonstration scale steam reforming system to examine the performance of the system. Results obtained in this study show that the temperature in the SR system was controlled under the self-regulation temperature, the concentration of CO and NOx in the off-gas were controlled less than 100ppm and 250ppm respectively, the distribution ratio of uranium to off-gas treatment system was under 0.12% and the gasification ratio of waste TBP was more than 99%. This long-term waste treatment test has demonstrated that the SR system can safely and effectively reduce the volume of the waste.

Journal Articles

Steam-assisted pyrolysis system for decontamination and volume reduction of radioactive organic waste

Sasaki, Toshiki; Sone, Tomoyuki; Koyama, Hayato; Yamaguchi, Hiromi

Journal of Nuclear Science and Technology, 46(3), p.232 - 238, 2009/03

 Times Cited Count:10 Percentile:56.98(Nuclear Science & Technology)

A demonstration scale steam reforming treatment system was tested for the treatment of waste tri-n-butyl phosphate/n-dodecane contaminated uranium and simulated halogenated organic wastes stored in the Japan Atomic Energy Agency. The steam reforming treatment system was designed for the organic waste which produced a lot of acidic compounds by incineration and gave severe damage to incinerators. The system comprises a gasification process for decontamination by pyrolysis and steam reforming in a gasification chamber and a destruction process by oxidation with heated air in a submerged combustion type reactor for corrosion prevention. Wastes were reduced by 98 to 99.4% in weight during the treatment without any trouble by the acidic compounds. Almost all uranium was retained in the gasification chamber and uranium concentration of secondary waste water was very low that can permit the discharge of the neutralized waste water in the river.

Journal Articles

Development of the volume reduction treatment of solid waste system by ultra-high frequency induction furnace

Sakakibara, Tetsuro; Aoyama, Yoshio; Yamaguchi, Hiromi; Sasaki, Naoto*; Nishikawa, Takeshi*; Murata, Minoru*; Park, J.*; Taniguchi, Shoji*; Fujita, Michiru*; Fukuda, Tomoyuki*; et al.

Proceedings of International Waste Management Symposium 2009 (WM '09) (CD-ROM), 15 Pages, 2009/03

The volume reduction treatment of solid waste system by ultra-high frequency induction furnace (UHFIF) was developed from FY2005 to FY2007. Basic data for melting performance were collected by non-radioactive experiments using the bench scale UHFIF with a crucible capacity of 10 liters. Based on the obtained data, engineering specifications were evaluated for a demonstration scale UHFIF with a crucible capacity of 30 liters. A new demonstration scale UHFIF was constructed and melting experiments of surrogate wastes were carried out by this furnace. It was confirmed that the demonstration scale UHFIF can melt ferrous metal, ceramics and aluminum all together and stabilize aluminum by oxidation to alumina. Density, chemical composition, and surface condition of the solidified substances were analyzed, and homogeneity of the solidified substances was confirmed. Melting behavior in the demonstration scale UHFIF was analyzed by computer simulation and simulation results agreed well with the experimental ones. From the design study for a full scale UHFIF with a crucible capacity of 100 liters, basic specifications were evaluated for the full scale UHFIF. Based on the obtained specification, melting behavior in the full scale UHFIF was analyzed by computer simulation.

JAEA Reports

Stabilization of simulated radioactive lead waste and simulated low level radioactive liquid waste using reformed sulfur (Joint research)

Sone, Tomoyuki; Sasaki, Toshiki; Miyamoto, Yasuaki; Yamaguchi, Hiromi; Inoue, Haruka*; Kihara, Tsuyoshi*; Takei, Yoshihisa*; Tatekawa, Takaiki*; Fukaya, Masaaki*; Iriya, Keishiro*; et al.

JAEA-Technology 2008-032, 25 Pages, 2008/03

JAEA-Technology-2008-032.pdf:5.54MB

Reformed sulfur (RS) is superior in water interception and acid resistance compared with cement. Therefore solidified wastes with RS should have the high resistance to leaching. Unconfined compressive strength test and leaching test using solidified simulated wastes containing lead contaminated with radioactive nuclides (Lead waste) with RS and solidified simulated low level radioactive liquid waste (LLLW) with RS were conducted to examine the applicability of reformed sulfur solidification method (RSSM) as solidification technique of Lead waste and LLLW. The results of these studies show that RSSM is effective technique for stabilization of lead compared with cement solidification method because solidified lead with RS has much stronger resistance to leaching of lead than solidified lead with cement. It also show that the applicability of RSSM as solidification technique of the waste containing lead oxide and LLLW is low because the resistance to leaching of solidified lead oxide with RS and of solidified simulated LLLW with RS were equal to or lower than those of solidified products with cement respectively.

JAEA Reports

Treatment of waste TBP/n-dodecane with steam reforming system

Sone, Tomoyuki; Nonaka, Kazuharu; Sasaki, Toshiki; Yamaguchi, Hiromi

JAEA-Technology 2008-006, 23 Pages, 2008/03

JAEA-Technology-2008-006.pdf:3.54MB

Steam reforming method consists of the gasification process (GP) in which organics are vaporized and decomposed with superheated steam and the oxidation process in which vaporized organics are decomposed with heated air. Experimental study in which waste TBP/n-dodecane (WTBP) containing uranium was used was conducted with the steam reforming system (SRS) to examine the distribution ratio of uranium in the system, the feasibility of treatment of WTBP and the effect of treatment with SRS on the volume reduction of WTBP. The results of these studies are as follows: (1) Most of uranium compounds in WTBP are separated from organics in GP. (2) Only the solid waste remained in GP is the radioactive secondary waste from the treatment of WTBP with SRS. (3) The maintenance operation of the equipments installed downstream of GP become easy to perform. (4) The volume of secondary solid wastes is very small because more than 99% of the WTBP were evaporated in GP. (5) It was estimated that the effect of treatment with SRS on the volume reduction of WTBP is 30 times more than that of pyrolysis method. These results show that SRS can achieve high volume reduction of WTBP.

JAEA Reports

Treatment of simulated waste TBP/n-dodecan and halogenated oils with steam reforming system

Sone, Tomoyuki; Nonaka, Kazuharu; Sasaki, Toshiki; Yamaguchi, Hiromi

JAEA-Technology 2007-063, 42 Pages, 2008/01

JAEA-Technology-2007-063.pdf:2.17MB

Steam reforming method has been developed for the treatment of organic wastes which are not suitable materials (tributyl phosphate, halogenated oil) for the incineration due to large quantities of secondary wastes generation. Process demonstration tests were conducted with the demonstration scale steam reforming system to examine the feasibility of treatment of simulated waste solvent (TBP and n-dodecane mixture) and simulated waste oils (halogenated oils and mineral oil mixture). These tests were also conducted to optimize the process conditions. The results of these studies are as follows: (1)More than 98wt% of the simulated wastes were evaporated in the gasification process. Solid residues removed from the gasification process as secondary wastes were inorganic compounds. (2)While the simulated waste oils were treated, the stacking of the filter is reduced by increasing the feed rate of steam from 1.5 kg/h to 3.0 kg/h. (3)Most of phosphoric acids produced by thermal decomposition of TBP were vaporized in the gasification process at 600$$sim$$650$$^{circ}$$C. This result shows that volume of radioactive secondary waste can be effectively reduced.

Journal Articles

Reduction of radioactive secondary waste with steam reforming in treatment of waste TBP/dodecane

Sone, Tomoyuki; Sasaki, Toshiki; Yamaguchi, Hiromi

Proceedings of 11th International Conference on Environmental Remediation and Radioactive Waste Management (ICEM '07) (CD-ROM), 5 Pages, 2007/00

We have stored waste TBP/dodecane generated from R&D activities on recycle of nuclear fuel. Those wastes can be incinerated, however a large quantity of contaminated phosphorous compounds generate. The objective of this study is to reduce the generation of radioactive secondary waste by the treatment of those wastes using steam reforming system. We conducted process demonstration tests using waste TBP/dodecane with 0.07g/L of uranium. We studied the temperature dependence of the gasification ratio of inorganic phosphorus compounds and removal of uranium by the filter. As the results, more than 95% of phosphorus compounds were gasified at temperature of 600$$^{circ}$$C or more, and more than 98% of uranium compounds were separated from the vaporized waste. The separated phosphorus compounds can be disposed of as the liquid wastes of which concentration of uranium is under the regulatory level. These results show the steam reforming system is effective in the reduction of radioactive secondary waste in the treatment of TBP/dodecane.

Journal Articles

Fuel-cladding chemical interaction in MOX fuel rods irradiated to high burnup in an advanced thermal reactor

Tanaka, Kosuke; Maeda, Koji; Sasaki, Shinji; Ikusawa, Yoshihisa; Abe, Tomoyuki

Journal of Nuclear Materials, 357(1-3), p.58 - 68, 2006/10

 Times Cited Count:9 Percentile:56.05(Materials Science, Multidisciplinary)

The performance of MOX fuel irradiated in the advanced thermal reactor, FUGEN, to the burnup of 47.5 GWd/t, was investigated by using a telescotpe, optical microscope, SEM and EPMA. Observations focused on elucidating the corrosion behavior of the cladding inner surface. A reaction layer was observed at burnups higher than about 35 GWd/t. The relationship between the thickness of the reaction layer and burnup was similar to that reported in the literature for conventional UO$$_{2}$$ fuel and other MOX fuels. The existence of a plutonium spot near the outer surface of the fuel pellet had no significant effect on the thickness of the reaction layer. A bonding layer was observed on the cladding inner surface. Its morphology and elemental distributions were not so different from those in BWR UO$$_{2}$$ fuel pins irradiated to high burnup, in which the fission gas release rate is high. In addition, the dependences of bonding layer formation on the burnup and linear heat rating were similar to results of UO2 fuel pins. It was, thus, suggested that the bonding layer formation mechanism was similar in both UO2 and MOX fuel pins.

Journal Articles

Hole-induced novel spin state within Haldane gap in Nd$$_{2-x}$$Ca$$_x$$BaNiO$$_5$$

Sasaki, Tomoyuki*; Yokoo, Tetsuya*; Katano, Susumu; Akimitsu, Jun*

Journal of the Physical Society of Japan, 74(1), p.267 - 270, 2005/01

 Times Cited Count:2 Percentile:20.49(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

MOGRA-DB; Database system for migration prediction code MOGRA

Amano, Hikaru; Ikeda, Hiroshi*; Sasaki, Toshihisa*; Matsuoka, Shungo*; Kurosawa, Naohiro*; Takahashi, Tomoyuki*; Uchida, Shigeo*

KEK Proceedings 2003-11, p.239 - 244, 2003/11

A Code MOGRA (Migration Of GRound Additions) is a migration prediction code for toxic ground additions including radioactive materials in a terrestrial environment, which consists of computational codes that are applicable to various evaluation target systems, and can be used on personal computers. The computational code has the dynamic compartment analysis block at its core, the graphical user interface (GUI) for model formation, computation parameter settings, and results displays. The code MOGRA has varieties of databases, which is called MOGRA-DB. Another additional code MOGRA-MAP can take in graphic map and calculate the square measure about the target land.

JAEA Reports

Questionnaire on the measurement condition of distribution coefficient

Takebe, Shinichi; Kimura, Hideo; Matsuzuru, Hideo; Takahashi, Tomoyuki*; Yasuda, Hiroshi*; Uchida, Shigeo*; Mahara, Yasunori*; Saeki, Akiyoshi*; Sasaki, Noriyuki*; Ashikawa, Nobuo*; et al.

JAERI-Review 2001-015, 81 Pages, 2001/05

JAERI-Review-2001-015.pdf:5.94MB

no abstracts in English

Journal Articles

Intercomparison of measurements and questionnaire on the distribution coefficient

Takahashi, Tomoyuki*; Takebe, Shinichi; Kimura, Hideo; Matsuzuru, Hideo; Yasuda, Hiroshi*; Uchida, Shigeo*; Saeki, Akiyoshi*; Mahara, Yasunori*; Sasaki, Noriyuki*; Ashikawa, Nobuo*; et al.

KURRI-KR-44, p.169 - 176, 2000/02

no abstracts in English

JAEA Reports

Intercomparison on measurement of distribution coefficient; Investigation on differences of measured values between individuals

Takahashi, Tomoyuki; Takebe, Shinichi; Kimura, Hideo; Matsuzuru, Hideo; Yasuda, Hiroshi*; Uchida, Shigeo*; Saeki, Akiyoshi*; Mahara, Yasunori*; Sasaki, Noriyuki*; *; et al.

JAERI-Research 97-089, 25 Pages, 1997/12

JAERI-Research-97-089.pdf:1.11MB

no abstracts in English

42 (Records 1-20 displayed on this page)