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Noguchi, Hiroki; Kamiji, Yu; Tanaka, Nobuyuki; Takegami, Hiroaki; Iwatsuki, Jin; Kasahara, Seiji; Myagmarjav, O.; Imai, Yoshiyuki; Kubo, Shinji
International Journal of Hydrogen Energy, 46(43), p.22328 - 22343, 2021/06
Times Cited Count：12 Percentile：59.85(Chemistry, Physical)An iodine-sulfur process offers the potential for mass producing hydrogen with high-efficiency, and it uses high-temperature heat sources, including HTGR, solar heat, and waste heat of industries. R&D tasks are essential to confirm the integrity of the components that are made of industrial materials and the stability of hydrogen production in harsh working conditions. A test facility for producing hydrogen was constructed from corrosion-resistant components made of industrial materials. For stable hydrogen production, technical issues for instrumental improvements (i.e., stable pumping of the HIx solution, improving the quality control of glass-lined steel, prevention of I
precipitation using a water removal technique in a Bunsen reactor) were solved. The entire process was successfully operated for 150 h at the rate of 30 L/h. The integrity of components and the operational stability of the hydrogen production facility in harsh working conditions were demonstrated.
Nara, Yoshitaka*; Kuwatani, Ryuta*; Kono, Masanori*; Sato, Toshinori; Kashiwaya, Koki*
Zairyo, 67(7), p.730 - 737, 2018/07
Information of confining ability of rock is important for the geological disposal of radioactive wastes. To maintain or improve the confining ability of rocks, it is important to seal pores and cracks. In this study, we investigated the precipitation of minerals on the rock surface. As rock samples, we used Berea sandstone and Toki granite in this study. It was shown that precipitation occurred on the surface of rock specimens kept in calcium hydroxide solution for 1 month if the concentration was high. Specifically, if the concentration of calcium hydroxide solution was higher than 300 mg/l, the precipitation occurred obviously. After keeping rock specimens in calcium hydroxide solution, the weight of the rock samples increased and the concentration of calcium ion decreased by the precipitation. It is considered that the calcium ion in water was used for the precipitation on rock surfaces. Since the precipitation has been recognized for rock surfaces, it is possible to seal pores and cracks in rocks. Therefore, it is also possible to keep or decrease the permeability of rocks by the precipitation of calcium compounds.
Kobayashi, Fuyumi; Sumiya, Masato; Kida, Takashi; Kokusen, Junya; Uchida, Shoji; Kaminaga, Jota; Oki, Keiichi; Fukaya, Hiroyuki; Sono, Hiroki
JAEA-Technology 2016-025, 42 Pages, 2016/11
JAEA-Technology-2016-025.pdf:17.88MB
A preliminary test on MOX fuel dissolution for the STACY critical experiments had been conducted in 2000 through 2003 at Nuclear Science Research Institute of JAEA. Accordingly, the uranyl / plutonium nitrate solution should be reconverted into oxide powder to store the fuel for a long period. For this storage, the moisture content in the oxide powder should be controlled from the viewpoint of criticality safety. The stabilization of uranium / plutonium solution was carried out under a precipitation process using ammonia or oxalic acid solution, and a calcination process using a sintering furnace. As a result of the stabilization operation, recovery rate was 95.6% for uranium and 95.0% for plutonium. Further, the recovered oxide powder was calcined again in nitrogen atmosphere and sealed immediately with a plastic bag to keep its moisture content low and to prevent from reabsorbing atmospheric moisture.
Morita, Yasuji; Kawata, Yoshihisa*; Mineo, Hideaki; Koshino, Nobuyoshi*; Asanuma, Noriko*; Ikeda, Yasuhisa*; Yamasaki, Kazuhiko*; Chikazawa, Takahiro*; Tamaki, Yoshihisa*; Kikuchi, Toshiaki*
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10
N-cyclohexyl-2-pyrrolidone (NCP) can selectively precipitate U(VI) ions in aqueous nitric acid solutions. Utilizing this property, we have been developing a simple reprocessing process of spent nuclear fuel based only on precipitation method. In the first precipitation step, only U is separated by precipitation in a yield of about 70%, and in the second precipitation step both U and Pu are recovered and separated from fission products (FP) and other transuranium elements (TRU). In JAERI, precipitation behaviors of Pu and other TRU were examined experimentally, and the results showed the feasibility of the process establishement.
Yamasaki, Kazuhiko*; Chikazawa, Takahiro*; Tamaki, Yoshihisa*; Kikuchi, Toshiaki*; Morita, Yasuji; Kawata, Yoshihisa*; Mineo, Hideaki; Koshino, Nobuyoshi*; Asanuma, Noriko*; Harada, Masayuki*; et al.
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 4 Pages, 2005/10
N-cyclohexyl-2-pyrrolidone (NCP), can selectively precipitate U(VI) ions in aqueous nitric acid solutions. Utilizing this property, we have been developing a simple reprocessing process of spent nuclear fuel based only on precipitation method. In the first precipitation step, only U is separated by precipitation in a yield of about 70%, and in the second precipitation step both U and Pu are recovered and separated from fission products (FP) and other transuranium elements (TRU). In the present study, a precipitator and a precipitate separator were designed and built up, and were tested with aspets of operationability and system performance.
Morita, Yasuji; Kubota, Masumitsu*
JAERI-Review 2005-041, 35 Pages, 2005/09
JAERI-Review-2005-041.pdf:2.24MB
Research and development on Partitioning in JAERI are reviewed in the present report from the beginning to the development of the 4-Group Partitioning Process and its test with real high-level liquid waste (HLLW). In the 3-Group Partitioning Process established in around 1980, elements in HLLW are separated into 3 groups of transuranium element group, Sr-Cs group and the other element group. The 4-Group Partitioning Process subsequently developed contains the separation of Tc-platinum group metals additionally. The process was tested to demonstrate its performance with real concentrated HLLW. Until then, various separation methods for various elements were studied and selection and optimization of the separation methods were carried out to establish the process. Review of the experience, findings and results is very important and valuable for future study on partitioning. The present report is prepared from this point of view.
Cs deposition due to the Chernobyl nuclear accidentTerada, Hiroaki; Chino, Masamichi
Journal of Nuclear Science and Technology, 42(7), p.651 - 660, 2005/07
Times Cited Count：18 Percentile：74.92(Nuclear Science & Technology)The prediction performance of WSPEEDI (Worldwide version of System for Prediction of Environmental Emergency Dose Information), which consists of the atmospheric dynamic model MM5 and the Lagrangian particle dispersion model GEARN-new, is evaluated by measurements of precipitation and surface deposition of Cs over Europe during the Chernobyl accident. It is concluded that MM5/GEARN-new can predict Cs deposition distribution with good accuracy when accurate precipitation is predicted by using a explicit scheme on cloud microphysics with ice phase processes. High-resolutional calculation is also conducted for the area surrounding Chernobyl by a nesting method. MM5/GEARN-new can predict quite a realistic distribution of Cs deposition around Chernobyl which was not calculated by the previous version.
Iwase, Akihiro; Hasegawa, Tadayuki*; Chimi, Yasuhiro; Tobita, Toru; Ishikawa, Norito; Suzuki, Masahide; Kambara, Tadashi*; Ishino, Shiori*
Nuclear Instruments and Methods in Physics Research B, 195(3-4), p.309 - 314, 2002/10
Times Cited Count：12 Percentile：60.82(Instruments & Instrumentation)no abstracts in English
Tobita, Toru; Suzuki, Masahide; Iwase, Akihiro; Aizawa, Kazuya
Journal of Nuclear Materials, 299(3), p.267 - 270, 2001/12
Times Cited Count：19 Percentile：84.88(Materials Science, Multidisciplinary)no abstracts in English
Naramoto, Hiroshi; Yamamoto, Shunya; Narumi, Kazumasa
JAERI-Review 99-025, TIARA Annual Report 1998, p.191 - 192, 1999/10
no abstracts in English
Furuno, Akiko; Yamazawa, Hiromi
Mathematics and Computation, Reactor Physics and Environmental Analysis in Nuclear Applications, 2, p.1699 - 1704, 1999/00
no abstracts in English
; *
Nuclear Technology, 122(3), p.265 - 275, 1998/00
Times Cited Count：2 Percentile：24.49(Nuclear Science & Technology)no abstracts in English
*; *; *; *; Sakamoto, Yoshiaki; *; *; ; Nagasaki, Shinya*; *; et al.
Nihon Genshiryoku Gakkai-Shi, 37(1), p.59 - 77, 1995/00
Times Cited Count：12 Percentile：74.11(Nuclear Science & Technology)no abstracts in English
Uchiyama, Gunzo; Maeda, Mitsuru; *; Fujine, Sachio; *; *
Proceedings of 4th International Conference on Nuclear Fuel Reprocessing and Waste Management; RECOD '94, Vol.3, 0, p.1 - 15, 1994/00
no abstracts in English
; Kimura, Takaumi
Journal of Nuclear Science and Technology, 28(8), p.780 - 783, 1991/08
no abstracts in English
Radioisotopes, 35(11), p.571 - 576, 1986/11
no abstracts in English
Kumazawa, Shigeru; *
Oyo Tokeigaku, 15(1), p.1 - 14, 1986/00
no abstracts in English
1982); ; ; ;
JAERI-M 83-201, 40 Pages, 1983/11
no abstracts in English
;
Journal of Nuclear Science and Technology, 17(5), p.370 - 376, 1980/00
Times Cited Count：1 Percentile：22.79(Nuclear Science & Technology)no abstracts in English
*; *;
Radiochem.Radioanal.Lett., 43(4), p.203 - 214, 1980/00
no abstracts in English
JAERI-M 6390, 27 Pages, 1976/02
no abstracts in English
