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.

Development of security and safety fuel for Pu-burner HTGR, 2; Design study of fuel and reactor core

Goto, Minoru; Ueta, Shohei; Aihara, Jun; Inaba, Yoshitomo; Fukaya, Yuji; Tachibana, Yukio; Okamoto, Koji*

Proceedings of 25th International Conference on Nuclear Engineering (ICONE-25) (CD-ROM), 6 Pages, 2017/07

A PuO-YSZ fuel kernel with a ZrC coating, which enhances safety, security and safeguard, namely: 3S-TRISO fuel, was proposed to introduce to the plutonium-burner HTGR. In this study, the efficiency of the ZrC coating as the free-oxygen getter was examined based on a thermochemical calculation. A preliminary study on the feasibility of the 3S-TRISO fuel was conducted focusing on the internal pressure. Additionally, a nuclear feasibility of the reactor core was studied. As a result, all the amount of the free-oxygen is captured by a thin ZrC coating under 1600C and coating ZrC on the fuel kernel should be very effective method to suppress the internal pressure. The internal pressure of the 3S-TRISO fuel at 500 GWd/t is lower than that of UO kernel TRISO fuel whose feasibility had been already confirmed and the 3S-TRISO fuel should be feasible. The fuel shuffling allows to achieve 500 GWd/t. The temperature coefficient of reactivity is negative during the operation period and thus the nuclear feasibility of the reactor core should be achievable.

Conceptual study of a plutonium burner high temperature gas-cooled reactor with high nuclear proliferation resistance

Goto, Minoru; Demachi, Kazuyuki*; Ueta, Shohei; Nakano, Masaaki*; Honda, Masaki*; Tachibana, Yukio; Inaba, Yoshitomo; Aihara, Jun; Fukaya, Yuji; Tsuji, Nobumasa*; et al.

Proceedings of 21st International Conference & Exhibition; Nuclear Fuel Cycle for a Low-Carbon Future (GLOBAL 2015) (USB Flash Drive), p.507 - 513, 2015/09

A concept of a plutonium burner HTGR named as Clean Burn, which has a high nuclear proliferation resistance, had been proposed by Japan Atomic Energy Agency. In addition to the high nuclear proliferation resistance, in order to enhance the safety, we propose to introduce PuO-YSZ TRISO fuel with ZrC coating to the Clean Burn. In this study, we conduct fabrication tests aiming to establish the basic technologies for fabrication of PuO-YSZ TRISO fuel with ZrC coating. Additionally, we conduct a quantitative evaluation of the security for the safety, a design of the fuel and the reactor core, and a safety evaluation for the Clean Burn to confirm the feasibility. This study is conducted by The University of Tokyo, Japan Atomic Energy Agency, Fuji Electric Co., Ltd., and Nuclear Fuel Industries, Ltd. It was started in FY2014 and will be completed in FY2017, and the first year of the implementation was on schedule.

Preliminary evaluation of integrity of coated fuel particles under normal operation in core of small-sized HTGR system HTR50S at 1st. step of Phase I

Aihara, Jun; Goto, Minoru; Inaba, Yoshitomo; Isaka, Kazuyoshi; Ohashi, Hirofumi; Tachibana, Yukio

JAEA-Technology 2014-009, 29 Pages, 2014/05

JAEA-Technology-2014-009.pdf:3.51MB

Japan Atomic Energy Agency (JAEA) is carrying out conceptual design of a 50 MWt small-sized high temperature gas cooled reactor (HTGR), HTR50S. In this report, integrity of coated fuel particles (CFPs) is evaluated for core of HTR50S of 1st. step of phase I (first core of HTR50S) under normal operation. CFPs are considered to be failed by fuel kernel migration by temperature gradient in CFPs or corrosion of SiC layer by fission product Pd (Pd corrosion) or increase in internal pressure under normal operation. In this report, integrity of CFPs is to be maintained for each phenomenon.

Nuclear design study on a small-sized high temperature gas-cooled reactor with high burn-up fuel and axial fuel shuffling

Goto, Minoru; Seki, Yasuyoshi; Fukaya, Yuji; Inaba, Yoshitomo; Ohashi, Hirofumi; Sato, Hiroyuki; Tachibana, Yukio

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

Japan Atomic Energy Agency (JAEA) has started a conceptual design study of a small-sized High Temperature Gas-cooled Reactor (HTGR) with 50 MW thermal power (HTR50S) to be deployed in developing countries in the 2020s. The nuclear design of the HTR50S is performed by upgrading that of a High Temperature Engineering Test Reactor (HTTR), which is the Japanese HTGR with 30 MW thermal power. In the HTTR design, 12 kinds of fuel enrichment was used to optimize the power distribution. In the previous study of the HTR50S, we succeeded in reducing the number of the fuel enrichment to 3. The present study challenges the nuclear design for effective use of uranium by utilizing high burn-up fuel and axial fuel shuffling, in which a half of the loaded fuel elements is discharged from the core every 2 years and the remains are reloaded. The core burn-up calculations were performed and the nuclear characteristics were confirmed to satisfy the design requirement.

Conceptual design of small-sized HTGR system, 3; Core thermal and hydraulic design

Inaba, Yoshitomo; Sato, Hiroyuki; Goto, Minoru; Ohashi, Hirofumi; Tachibana, Yukio

JAEA-Technology 2012-019, 142 Pages, 2012/06

JAEA-Technology-2012-019.pdf:4.54MB

JAEA has started the conceptual designs of small-sized HTGR systems, aiming for the deployment in developing countries. The small-sized HTGR systems can provide power generation by steam turbine, high temperature steam for industry process and/or low temperature steam for district heating. As one of the conceptual designs in the first stage, the core thermal and hydraulic design of a power generation and steam supply small-sized HTGR with a thermal power of 50 MW (HTR50S) was carried out. HTR50S in the first stage has the same coated particle fuel as HTTR. The purpose of the design is to make sure that the maximum fuel temperature in normal operation doesn't exceed the design target. Following the design, safety analysis assuming a depressurization accident was carried out. The fuel temperature in the normal operation and the fuel and reactor pressure vessel temperatures in the depressurization accident were evaluated. As a result, it was cleared that the thermal integrity of the fuel and the reactor coolant pressure boundary is not damaged.

Nuclear design of small-sized high temperature gas-cooled reactor for developing countries

Goto, Minoru; Seki, Yasuyoshi; Inaba, Yoshitomo; Ohashi, Hirofumi; Sato, Hiroyuki; Fukaya, Yuji; Tachibana, Yukio

Proceedings of 2012 International Congress on Advances in Nuclear Power Plants (ICAPP '12) (CD-ROM), p.341 - 348, 2012/06

Japan Atomic Energy Agency has started a conceptual design of a small-sized HTGR with 50 MW thermal power (HTR50S), which is a first-of-a-kind commercial or demonstration plant of a small-sized HTGR to be deployed in developing countries in the 2020s. The nuclear of the HTR50S was performed by upgrading the proven technology of High Temperature Engineering Test Reactor (HTTR) to reduce cost for the construction. In the nuclear design, reduce the number of fuel enrichment comparing with the HTTR is one of the important subject to be upgraded. The optimization of the power distribution in the core, which is required to suppress the maximum fuel temperature below the limitation, was completed successfully by using only three fuel enrichment and the number of fuel enrichment was reduced significantly compared with the HTTR.

Study on Mo production method with irradiation of circulating Mo solution, 1; Results of cold tests (preliminary tests)

Inaba, Yoshitomo; Ishikawa, Koji*; Ishida, Takuya; Ishitsuka, Etsuo; Kurosawa, Kiyoko*; Hishinuma, Yukio*; Tatenuma, Katsuyoshi*

no journal, , 

The circulating solution irradiation method is a new production method of Mo, which is the parent nuclide of Tc used as medical diagnosis medicine. In order to realize this method, compatibility between molybdenum solutions and structural materials, etc. were investigated. As a result, it was found that the potassium molybdate solution have good characteristics as an irradiation target.

Conceptual design study of small-sized high temperature gas-cooled reactor for developing countries, 2; Nuclear and thermal design

Goto, Minoru; Inaba, Yoshitomo; Fukaya, Yuji; Ohashi, Hirofumi; Tachibana, Yukio; Nakano, Masaaki*; Tanabe, Kenichi*

no journal, , 

Japan Atomic Energy Agency (JAEA) has started a conceptual design of a small-sized HTGR with 50 MW thermal power (HTR50S). It is a first-of-a-kind commercial or demonstration plant of a small-sized HTGR to be deployed in developing countries in the 2020s. The design policy of the HTR50S is to construct it without development of new technologies as possible, which require additional demonstration tests, to suppress the construction cost and deploy it in 2020s. Accordingly, the nuclear and thermal design of the HTR50S was performed by upgrading the proven design technology of the High Temperature Engineering Test Reactor (HTTR). We challenged to increase the power density and decrease the number of the fuel enrichments compared with the HTTR. Additionally, we challenges the nuclear and thermal design for effective utilization of uranium by utilizing high burn-up fuel and axial fuel shuffling.

Nuclear and thermal design for high temperature gas-cooled reactor with SiC matrix fuel

Goto, Minoru; Inaba, Yoshitomo; Aihara, Jun; Ueta, Shohei; Tachibana, Yukio

no journal, , 

JAEA has performed the research and development of the SiC matrix fuel, which is an oxidation resistant fuel against an air ingress accident, to establish the fundamental technologies. In this study, a nuclear thermal design was performed for the HTGR with the SiC matrix fuel.