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Isogawa, Hiroki*; Naoi, Motomasa*; Yamasaki, Seiji*; Ho, H. Q.; Katayama, Kazunari*; Matsuura, Hideaki*; Fujimoto, Nozomu*; Ishitsuka, Etsuo
JAEA-Technology 2022-015, 18 Pages, 2022/07
JAEA-Technology-2022-015.pdf:1.37MB
As a summer holiday practical training 2021, the impact of 10 years long-term shutdown on critical control rod position of the HTTR and the delayed neutron fraction (
) of the VHTRC-1 core were investigated using Monte-Carlo MVP code. As a result, a long-term shutdown of 10 years caused the critical control rods of the HTTR to withdraw about 4.0
0.8 cm compared to 3.9 cm in the experiment. The change in critical control rods position of the HTTR is due to the change of some fission products such as 
Pu, Am, 
Pm, Sm, 
Gd. Regarding the calculation of the VHTRC-1 core, the value is underestimate of about 10% in comparison with the experiment value.
Hamamoto, Shimpei; Ishitsuka, Etsuo; Nakagawa, Shigeaki; Goto, Minoru; Matsuura, Hideaki*; Katayama, Kazunari*; Otsuka, Teppei*; Tobita, Kenji*
Proceedings of 2021 International Congress on Advances in Nuclear Power Plants (ICAPP 2021) (USB Flash Drive), 5 Pages, 2021/10
Impurity concentrations of hydrogen and hydride in the coolant were investigated in detail for the HTTR, a block type high-temperature gas reactor owned by Japan. As a result, it was found that CH
was 1/10 of H
concentration, which was under the conventional detection limit. If the ratio of H to CH in the coolant is the same as the ratio of HT to CH
T, the CHT has a larger dose conversion factor, and this compositional ratio is an important finding for the optimal dose evaluation. Further investigation of the origin of CH suggested that CH was produced as a result of a thermal equilibrium reaction rather than being released as an impurity from the core.
Goto, Minoru; Okumura, Keisuke; Nakagawa, Shigeaki; Inaba, Yoshitomo; Matsuura, Hideaki*; Nakaya, Hiroyuki*; Katayama, Kazunari*
Fusion Engineering and Design, 136(Part A), p.357 - 361, 2018/11
Times Cited Count：6 Percentile：51.86(Nuclear Science & Technology)A High Temperature Gas-cooled Reactor (HTGR) is proposed as a tritium production device, which has the potential to produce a large amount of tritium using 
Li(n,
)T reaction. In the HTGR design, generally, boron is loaded into the core as a burnable poison to suppress excess reactivity. In this study, lithium is loaded into the HTGR core instead of boron and is used as a burnable poison aiming to produce thermal energy and tritium simultaneously. The nuclear characteristics and the fuel temperature were calculated to confirm the feasibility of the lithium-loaded HTGR. It was shown that the calculation results satisfied the design requirements and hence the feasibility was confirmed for the lithium-loaded HTGR, which produce thermal energy and tritium.
Katayama, Kazunari*; Ushida, Hiroki*; Matsuura, Hideaki*; Fukada, Satoshi*; Goto, Minoru; Nakagawa, Shigeaki
Fusion Science and Technology, 68(3), p.662 - 668, 2015/10
Times Cited Count：16 Percentile：78.98(Nuclear Science & Technology)Tritium production utilizing nuclear reactions by neutron and lithium in a high-temperature gas-cooled reactor is attractive for development of a fusion reactor. From viewpoints of tritium safety and production efficiency, tritium confinement technique is an important issue. It is known that alumina has high resistance for gas permeation. In this study, hydrogen permeation experiments in commercial alumina tubes were conducted and hydrogen permeability, diffusivity and solubility was evaluated. By using obtained data, tritium permeation behavior from an AlO-coated Li-compound particle was simulated. Additionally, by using literature data for hydrogen behavior in zirconium, an effect of Zr incorporation into an AlO coating on tritium permeation was discussed. It was indicated that the majority of produced tritium was released through the AlO coating above 500
C. However, it is expected that total tritium leak is suppressed to below 0.67% of total tritium produced at 500C by incorporating Zr fine particles into the inside of AlO coating.
Kawamoto, Yasuko*; Nakaya, Hiroyuki*; Matsuura, Hideaki*; Katayama, Kazunari*; Goto, Minoru; Nakagawa, Shigeaki
Fusion Science and Technology, 68(2), p.397 - 401, 2015/09
Times Cited Count：1 Percentile：9.61(Nuclear Science & Technology)To start up a fusion reactor, it is necessary to provide a sufficient amount of tritium from an external device. Herein, methods for supplying a fusion reactor with tritium are discussed. Use of a high temperature gas cooled reactor (HTGR) as a tritium production device has been proposed. So far, the analyses have been focused only on the operation in which fuel is periodically exchanged (batch) using the block type HTGR. In the pebble bed type HTGR, it is possible to design an operation that has no time loss for refueling. The pebble bed type HTGR (PBMR) and the block type HTGR (GTHTR300) are assumed as the calculation and comparison targets. Simulation is made using the continuous-energy Monte Carlo transport code MVPBURN. It is shown that the continuous operation using the pebble bed type HTGR has almost the same tritium productivity compared with the batch operation using the block type HGTR. The issues for pebble bed type HTGR as a tritium production device are discussed.
Nakaya, Hiroyuki*; Matsuura, Hideaki*; Katayama, Kazunari*; Goto, Minoru; Nakagawa, Shigeaki
Proceedings of 2015 International Congress on Advances in Nuclear Power Plants (ICAPP 2015) (CD-ROM), p.398 - 402, 2015/05
The performance of tritium production for fusion reactor using High-Temperature Gas-cooled Reactor (HTGR) is studied. An influence of Li concentration on tritium production performance using HTGR is estimated. Li compound is loaded in the reactor core using Li rod consisting cylindrical Li compound in cladding tube. A Gas Turbine High-Temperature Reactor of 300 MWe nominal capacity (GTHTR300) with 600 MW thermal output power is assumed as HTGR. An amount of tritium production is estimated by burn-up calculations using the continuous-energy Monte Carlo transport code MVP-BURN. The amount of tritium outflow is estimated from equilibrium solution for the tritium diffusion equation in the cladding tube. Even if 6Li is enriched, the GTHTR300 can produce 500 g of tritium over 180-day operation without increasing the amount of required Li. The amount of tritium outflow is decreased by 20-50%.
Fukada, Satoshi*; Katayama, Kazunari*; Takeishi, Toshiharu*; Edao, Yuki; Kawamura, Yoshinori; Hayashi, Takumi; Yamanishi, Toshihiko
Fusion Science and Technology, 67(2), p.99 - 102, 2015/03
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Ding, F.*; Luo, G.-N.*; Pitts, R.*; Litnovsky, A.*; Gong, X.*; Ding, R.*; Mao, H.*; Zhou, H.*; Wampler, W. R.*; Stangeby, P. C.*; et al.
Journal of Nuclear Materials, 455(1-3), p.710 - 716, 2014/12
Times Cited Count：25 Percentile：87.95(Materials Science, Multidisciplinary)Fukada, Satoshi*; Edao, Yuki*; Sato, Koichi*; Takeishi, Toshiharu*; Katayama, Kazunari*; Kobayashi, Kazuhiro; Hayashi, Takumi; Yamanishi, Toshihiko; Hatano, Yuji*; Taguchi, Akira*; et al.
Fusion Engineering and Design, 87(1), p.54 - 60, 2012/01
Times Cited Count：4 Percentile：31.65(Nuclear Science & Technology)An experimental study on tritium (T) transfer in porous concrete for the tertiary T safety containment is performed to investigate (1) how fast HTO penetrates through concrete walls, (2) how well concrete walls contaminated with water-soluble T are decontaminated by a solution-in-water technique, and (3) how well hydrophobic paint coating works as a protecting film against HTO migrating through concrete walls. The epoxy paint coating can work as a HTO diffusion barrier and the PRF value is around 1/10. The silicon paint coating cannot work as the anti-T permeation barrier, because water deteriorates contact between the paint and cement or mortar.
Takata, Hiroki*; Furuichi, Kazuya*; Nishikawa, Masabumi*; Fukada, Satoshi*; Katayama, Kazunari*; Takeishi, Toshiharu*; Kobayashi, Kazuhiro; Hayashi, Takumi; Namba, Haruyuki*
Fusion Science and Technology, 54(1), p.223 - 226, 2008/07
Times Cited Count：9 Percentile：52.61(Nuclear Science & Technology)Concentration profiles of tritium penetrated into cement paste, mortar and concrete were measured by using samples with a shape of column. Tritium penetrated until a location of about 5 cm from the exposed surface after 6 months' exposure. The amount of tritium penetrated into mortar and concrete were less than 70% and half that into cement paste.
Takeishi, Toshiharu*; Katayama, Kazunari*; Nishikawa, Masabumi*; Masaki, Kei; Miya, Naoyuki
Journal of Nuclear Materials, 349(3), p.327 - 338, 2006/03
Times Cited Count：6 Percentile：41.26(Materials Science, Multidisciplinary)no abstracts in English
Takeishi, Toshiharu*; Katayama, Kazunari*; Nishikawa, Masabumi*; Miya, Naoyuki; Masaki, Kei
Fusion Science and Technology, 48(1), p.565 - 568, 2005/07
Times Cited Count：1 Percentile：10.41(Nuclear Science & Technology)no abstracts in English
Katayama, Kazunari*; Takeishi, Toshiharu*; Nagase, Hiroyasu*; Manabe, Yusuke*; Nishikawa, Masabumi*; Miya, Naoyuki; Masaki, Kei
Fusion Science and Technology, 48(1), p.561 - 564, 2005/07
Times Cited Count：1 Percentile：10.41(Nuclear Science & Technology)no abstracts in English
Katayama, Kazunari*; Takeishi, Toshiharu*; Manabe, Yusuke*; Nagase, Hiroyasu*; Nishikawa, Masabumi*; Miya, Naoyuki
Journal of Nuclear Materials, 340(1), p.83 - 92, 2005/04
Times Cited Count：8 Percentile：48.93(Materials Science, Multidisciplinary)no abstracts in English
Ida, Yuma*; Matsuura, Hideaki*; Nagasumi, Satoru; Okamoto, Ryo*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; et al.
no journal, ,
Large quantity of tritium is demanded for starting up of fusion reactor and engineering test using tritium for fusion blanket system. However, tritium is very rare and kg order of tritium must be produced artificially. Tritium production, by Li(n,)T reaction using the high temperature gas-cooled reactor (HTGR), has been proposed. In this method, loading of Li rods into burnable poison (BP) holes in HTGR is considered. In this paper, the Li rod suited to the demand for the utilization in High Temperature engineering Test Reactor (HTTR) is designed, and tritium production and leakage from Li-rod capsule are evaluated by adjusting the thickness of LiAlO, alumina, and Zr layers. A scenario of irradiation test supposed to be conducted at HTTR for demonstration of the tritium production and containment performance of the Li rod is presented.
C) conditionsOkamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Suganuma, Takuro*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; et al.
no journal, ,
It has been proposed that lithium rods, which are cylindrical lithium compounds, are loaded into a HTGR and tritium for initial fusion reactors is produced by Li(n,)T reaction. In this study, it was discussed that the lithium rods are covered with zirconium layers to prevent the produced tritium leak. The solubility and diffusion coefficient of hydrogen in zirconium were measured and the effectiveness of the zirconium layers on prevention of tritium leakage was estimated with the measured values. As a result, the tritium leakage ratio with the zirconium layers was estimated two orders lower than that without the zirconium layers, and hence it was considered that the zirconium layer is very effective on the prevention of the tritium leakage.
Suematsu, Senri*; Katayama, Kazunari*; Izumino, Junichi*; Matsuura, Hideaki*; Otsuka, Teppei*; Fukada, Satoshi*; Goto, Minoru; Nakagawa, Shigeaki
no journal, ,
It has been proposed that lithium compounds are loaded into a HTGR and tritium for initial fusion reactors is produced by Li(n,)T reaction. Coating PyC layer on the lithium compounds could be one of the method for preventing the produced tritium leakage. In this study, hydrogen permeation experiment was performed to obtain tritium transmission coefficient in PyC, which is an important value to estimate the amount of the tritium leakage.
Koga, Yuki*; Matsuura, Hideaki*; Okamoto, Ryo*; Ida, Yuma*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Nagasumi, Satoru; et al.
no journal, ,
Large quantity of tritium is demanded for starting up of fusion reactor and engineering test using tritium for fusion blanket system. Tritium production, by Li(n, )T reaction using the high temperature gas-cooled reactor (HTGR), has been proposed and the method to produce tritium by loading the lithium rods as burnable poison in the reactor core has been studied. In this presentation, the design of lithium rods to be loaded to High Temperature engineering Test Reactor (HTTR) and its irradiation test plan to demonstrate tritium production are presented.
Okamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Nagasumi, Satoru
no journal, ,
A study on tritium production using a high-temperature gas-cooled reactor has been carried out and it was proposed that zirconium is loaded into the lithium irradiation capsule to confine tritium within the irradiation capsule under high temperature condition. In this study, zirconium loading method was examined by numerical calculations to improve the tritium confinement. As a result, it was found that improvement in the tritium confinement can be expected by loading spherical zirconium into the irradiation capsule.
Suganuma, Takuro*; Matsuura, Hideaki*; Okamoto, Ryo*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Tobita, Kenji*
no journal, ,
A study on the confinement of tritium, which is a fuel for fusion reactors and is produced by a HTGR, has been conducted for high temperature condition. The tritium is confined in the irradiation capsule with a zirconium layer. The relation between a H/Zr ratio and an apparent diffusion coefficient of tritium in the zirconium layer is needed to evaluate the tritium confinement performance of the irradiation capsule. This relation was examined with a experiment using deuteron. As a result, the apparent diffusion coefficient deceases with an increase of the H/Zr ratio. This phenomena should be caused by a generation of hydrogen. After that, the analysis for an amount of the release of the tritium from the irradiation capsule will be calculated using obtained data to evaluate the containment performance of the irradiation capsule.
