High temperature gas-cooled reactors

Takeda, Tetsuaki*; Inagaki, Yoshiyuki; Aihara, Jun; Aoki, Takeshi; Fujiwara, Yusuke; Fukaya, Yuji; Goto, Minoru; Ho, H. Q.; Iigaki, Kazuhiko; Imai, Yoshiyuki; et al.

High Temperature Gas-Cooled Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.5, 464 Pages, 2021/02

https://doi.org/10.1016/C2018-0-05383-9

As a general overview of the research and development of a High Temperature Gas-cooled Reactor (HTGR) in JAEA, this book describes the achievements by the High Temperature Engineering Test Reactor (HTTR) on the designs, key component technologies such as fuel, reactor internals, high temperature components, etc., and operational experience such as rise-to-power tests, high temperature operation at 950C, safety demonstration tests, etc. In addition, based on the knowledge of the HTTR, the development of designs and component technologies such as high performance fuel, helium gas turbine and hydrogen production by IS process for commercial HTGRs are described. These results are very useful for the future development of HTGRs. This book is published as one of a series of technical books on fossil fuel and nuclear energy systems by the Power Energy Systems Division of the Japan Society of Mechanical Engineers.

Study of container using hybrid technique for sulfuric acid decomposition of thermochemical water-splitting iodine-sulfur process

Ioka, Ikuo; Iwatsuki, Jin; Kuriki, Yoshiro*; Kawai, Daisuke*; Yokota, Hiroki*; Kubo, Shinji; Inagaki, Yoshiyuki; Sakaba, Nariaki

Mechanical Engineering Journal (Internet), 7(3), p.19-00377_1 - 19-00377_11, 2020/06

https://doi.org/10.1299/mej.19-00377

A thermochemical water-splitting iodine-sulfur processes (IS process) is one of candidates for the large-scale production of hydrogen with high cost performance. Severe corrosive environment which is thermal decomposition of sulfuric acid exists in the IS process. A hybrid material with the corrosion-resistance and the ductility was made by a plasma spraying and laser treatment. The specimen had excellent corrosion resistance in the condition of 95 mass% boiling sulfuric acid. This was attributed to the formation of SiO on the surface. To confirm the production characteristics of a container using the hybrid material, the container which has a welded part, a chamfer, a curved surface was experimentally made. There was no detachment in the plasma spraying and laser treated layer of the container after the laser treatment. It was confirmed that the construction of the container with high corrosion resistance in sulfuric acid was possible in the hybrid technique.

Components development for sulfuric acid processing in the IS process

Noguchi, Hiroki; Kubo, Shinji; Iwatsuki, Jin; Kasahara, Seiji; Tanaka, Nobuyuki; Imai, Yoshiyuki; Terada, Atsuhiko; Takegami, Hiroaki; Kamiji, Yu; Onuki, Kaoru; et al.

Nuclear Engineering and Design, 271, p.201 - 205, 2014/05

https://doi.org/10.1016/j.nucengdes.2013.11.032

The Japan Atomic Energy Agency has been conducting research and development on a thermochemical iodine-sulfur (IS) process. An examination is planned to verify the integrity of the components in the sulfuric acid decomposition section. A bayonet-type sulfuric acid decomposer made of SiC ceramics, a key component in the section, was test-fabricated. In parallel, a direct-contact heat exchanger (DCHX) is contemplated for use in the sulfuric acid decomposition section to simplify the process. Although the concept is very attractive, little is known about the heat and mass transfer behavior in the DCHX. Therefore, a test apparatus was constructed to measure the gas-phase mass transfer coefficients required for the optimal design of the DCHX. These coefficients of water were acquired and compared with an empirical correlation. The experimental data were in good agreement with those obtained from empirical correlation, and thus, the apparatus was confirmed to be reasonable.

Components for sulfuric acid processing in the IS process

Noguchi, Hiroki; Kubo, Shinji; Iwatsuki, Jin; Kasahara, Seiji; Tanaka, Nobuyuki; Imai, Yoshiyuki; Terada, Atsuhiko; Takegami, Hiroaki; Kamiji, Yu; Onuki, Kaoru; et al.

Proceedings of 6th International Topical Meeting on High Temperature Reactor Technology (HTR 2012) (USB Flash Drive), 6 Pages, 2012/10

The Japan Atomic Energy Agency (JAEA) has been conducting research and development on a thermochemical iodine-sulfur (IS) process. An examination is planned to verify the integrity of the components in the sulfuric acid decomposition section. A bayonet-type sulfuric acid decomposer made of SiC ceramics, a key component in the section, was test-fabricated. In parallel, a direct-contact heat exchanger (DCHX) is contemplated for use in the sulfuric acid decomposition section to simplify the process. Although the concept is very attractive, little is known about the heat and mass transfer behavior in the DCHX. Therefore, a test apparatus was constructed to measure the gas-phase mass transfer coefficients required for the optimal design of the DCHX. These coefficients of water were acquired and compared with an empirical correlation. The experimental data were in good agreement with those obtained from empirical correlation, and thus, the apparatus was confirmed to be reasonable.

Green hydrogen production by using nuclear energy for hydrogen steelmaking

Ogawa, Masuro; Kasahara, Seiji; Inagaki, Yoshiyuki; Noguchi, Hiroki

"Gurin Enerugi Seitetsu Kenkyukai" Seika Hokokusho, p.4 - 44, 2012/03

Green hydrogen production by using nuclear energy for hydrogen steelmaking is one of the candidates of CO emission reduction. Very high temperature reactor (VHTR) is the most appropriate reactor type among generation IV nuclear reactors. In Japan, a large-scale national R&D project for nuclear steelmaking had been carried out during 1973-1980. The process was: reforming of bottom residue of oil distillation using nuclear heat to produce reducing gas: direct reduction of ore to produce iron by the reforming gas. R&D of 6 themes had been conducted: total systems, high temperature heat exchangers, very high temperature resistant alloy, high temperature thermal insulation materials, reforming gas generators, and shaft furnaces to produce direct reduced iron. A new type nuclear steelmaking is proposed now by the requirement of technology and a new problem of CO reduction. The largest change is the shift of reducing gas to hydrogen. R&D of VHTR continues since the national project and thermochemical water splitting IS (iodine-sulfur) process has been studied for hydrogen production in Japan Atomic Energy Agency. Conceptual design of a hydrogen steelmaking process applying VHTR-IS process and direct reduction steelmaking with hydrogen had been carried out in Green Energy Steelmaking Research Group in Iron and Steel Institute of Japan during 2008-2012.

Electron spin resonance study on H, HD, HD, and HD in solid parahydrogen

Kumagai, Jun*; Inagaki, Hiroki*; Kariya, Susumu*; Ushida, Takahiro*; Shimizu, Yuta*; Kumada, Takayuki

Journal of Chemical Physics, 127(2), p.024505_1 - 024505_13, 2007/07

https://doi.org/10.1063/1.2748046

We carried out an electron spin resonance (ESR) study on hydrogen ion radicals produced by radiolysis of solid parahydrogen. We newly observed totally more than fifty resolved lines in irradiated solid parahydrogens. We assigned these lines to be isotope substituents of H-core H ions such as HD, HD, and HD throughout comparison of their ESR parameters with theoretical results. These results show conclusive evidence that H-core H ions are produced and stably trapped in irradiated solid hydrogens. We also observed a lowering symmetry on electron wave function in HD and HD, and isotope-substitution reactions such as H+DHD+H and H+HDHD+H.

Test-fabrication of hydrogen iodide decomposer for IS process

Iwatsuki, Jin; Noguchi, Hiroki; Kubo, Shinji; Kasahara, Seiji; Tanaka, Nobuyuki; Takegami, Hiroaki; Onuki, Kaoru; Inagaki, Yoshiyuki

no journal, , 

The Japan Atomic Energy Agency has been conducting R&D on IS process for the future hydrogen energy system. The basic technique for the closed-cycle hydrogen production has been developed and a membrane process is under study for the efficient hydrogen production. Presently, main efforts are devoted to examine the integrity of components made of industrial materials screened by corrosion tests in the IS process environments. So far, fabrication of HI decomposer as key component of the HI decomposition section was completed. Test-fabricated HI decomposer has a performance to produce hydrogen for 150 NL/h, and maximum pressure is 0.95 MPa, maximum temperature is 500C. The components are consisted of triple structure, pressure vessel, outer tube, and inner tube. In order to secure corrosion-resistance, alloy C-276 as corrosion-resistant material was used for component.

Interdiffusion behavior of Pu and Am in MOX fuels

Matsumoto, Taku; Arima, Tatsumi*; Inagaki, Yaohiro*; Idemitsu, Kazuya*; Morimoto, Kyoichi; Kato, Masato; Uno, Hiroki*; Tamura, Tetsuya*

no journal, , 

The diffusion couples of (UPuAm)O and UO were annealed at 1873K in an atmosphere of G that correspond to O/M = 2.00 or 1.96, and the concentration profile of each actinide elements around the interface was measured with EPMA. It was clearly found that the diffusion coefficient at O/M = 2.00 was about two orders of magnitude greater than that at O/M = 1.96. In addition, it was observed that grain boundary diffusion is so large compared to bulk one for O/M = 2.00. On the other hand, for O/M = 1.96, grain boundary and bulk diffusions of these actinides were not clearly observed.

Development of membrane Bunsen reactor in IS process for high efficient hydrogen production

Myagmarjav, O.; Inagaki, Yoshiyuki; Kubo, Shinji; Ioka, Ikuo; Tanaka, Nobuyuki; Iwatsuki, Jin; Noguchi, Hiroki; Kamiji, Yu; Sakaba, Nariaki

no journal, , 

no abstracts in English

R&D status of heat utilization technologies for high-temperature gas-cooled reactor and solar energy

Myagmarjav, O.; Iwatsuki, Jin; Tanaka, Nobuyuki; Noguchi, Hiroki; Kamiji, Yu; Ioka, Ikuo; Nomura, Mikihiro*; Yamaki, Tetsuya*; Tsuru, Toshinori*; Machida, Masato*; et al.

no journal, ,