Development of granulation system for simplified MOX pellet fabrication process

Ishii, Katsunori; Segawa, Tomoomi; Kawaguchi, Koichi; Suzuki, Masahiro

Proceedings of 2019 International Congress on Advances in Nuclear Power Plants (ICAPP 2019) (Internet), 5 Pages, 2019/05

Japan Atomic Energy Agency (JAEA) is developing a simplified pelletizing process for MOX fuel fabrication. In this process, the flowability of MOX powder produced by de-nitration conversion based on microwave heating, calcination, and reduction is improved using the wet granulation method. In a previous paper, to produce MOX granules of appropriate sizes for pelletizing them effectively, we proposed a granulation system composed of a wet granulator and a sizing machine. In the present work, we modernized the wet granulator, completed the granulation system by adding auxiliary equipment, and conducted performance tests of the granulation system with WO powder. The results of a performance test indicated that it is possible to convert raw powder into granules characterized by appropriate size and excellent flowability. The time required to process 5 kg of WO powder was about 70 min, which almost satisfies the target time.

A Design study of high electric power for fast reactor cooled by super critical light water

Koshizuka, Seiichi*

JNC TJ9400 2000-011, 102 Pages, 2000/03

JNC-TJ9400-2000-011.pdf:2.71MB

In order to evaluate the possibility to achieve high electric power by a fast reactor with supercritical light water, the design study was carried out on a large fast reactor core with high coolant outlet temperature (SCFR-H). Since the reactor coolant circuit uses once-through direct cycle where all feedwater flows through the core to the turbine at supercritical pressure, it is possible to design much simpler and more compact reactor systems and to achieve higher thermal efficiency than those of current light water reactors. The once-through direct cycle system is employed in current fossil-fired power plants. In the present study, three types of core were designed. The first is SCFR-H with blankets cooled by ascending flow, the second is SCFR-H with blankets cooled by descending flow and the third is SCFR-H with high thermal power. Every core was designed to achieve the thermal efficiency over 43%, positive coolant density reactivity coefficient and electric power over 1600MW. Core characteristics of SCFR-Hs were compared with those of SCLWR-H (electric power: 1212MW), which is a thermal neutron spectrum reactor cooled and moderated by supercritical light water, with the same diameter of the reactor pressure vessel. It was shown that SCFR-H could increase the electric power about l.7 times maximally. From the standpoint of the increase of a reactor thermal power, a fast reactor has advantages as compared with a thermal neutron reactor, because it can increase the power density by adopting tight fuel lattices and eliminating the moderator region. Thus, it was concluded that a reactor cooled by supercritical light water could further improve the cost competitiveness by using a fast neutron spectrum and achieving a higher thermal power.

Development of a power divider in the plane using posts in a rectangular waveguide for the next generation lower hybrid current drive antenna

Seki, Masami; Maebara, Sunao; ; Ikeda, Yoshitaka; Imai, Tsuyoshi; Hirokawa, Jiro*; Arai, Hiroyuki*

Fusion Engineering and Design, 36(2-3), p.281 - 287, 1997/05

https://doi.org/10.1016/S0920-3796(96)00699-0

no abstracts in English

Analysis of E-plane multi-junctional power divider for LHCD plasma heating

Ueda, Hiroyuki*; Takizawa, Yasuhiro*; Arai, Hiroyuki*; Seki, Masami; Maebara, Sunao;

Proceedings of 1996 Asia-Pacific Microwave Conference (APMC '96), 4 Pages, 1996/00

no abstracts in English

Conceptual design of integrated reactor with inherent safery

Asahi, Yoshiro; ; Kobayashi, Toshiki*

Nuclear Technology, 91, p.28 - 50, 1990/07

https://doi.org/10.13182/NT90-A34439

no abstracts in English

Development of simplified pelletizing process for fast reactor MOX fuels and demonstration experiment, 1; Advanced technology of microwave heating denitration method

Segawa, Tomoomi; Kawaguchi, Koichi; Ishii, Katsunori; Tsuchida, Hayahisa*; Fujiwara, Kota*; Kaneko, Akiko*; Abe, Yutaka*

no journal, , 

Development and demonstration of elemental technologies in simplified pellet fabrication method are developed. While the cylindrical vessel is expected to have a higher speed and capacity than the flat vessel, spilling phenomenon occurs, and device design optimization is required. The mechanism of flashing and spilling, and microwave heating characteristics of high loss solution are studied. The progress of the development of elemental technologies and microwave heating test results using simulated reprocessed solutions are reported. The dielectric loss of distilled water increased from the lower end to near the central axis, and water was internally heated, and then strong convection currents were formed with a large velocity vector from the center upward. In contrast, in KCl solution with 10 mass%, which has the same dielectric loss rate as the reprocessed solution, the outer periphery was heated and large convection was hardly generated, suggesting that heating is non-uniform.

Study on the condition of MOX granules suitable for constant die filling in MOX fuel pellet production

Akashi, Masatoshi; Nishina, Masahiro; Morimoto, Kyoichi; Kato, Yoshiyuki; Kato, Masato

no journal, , 

A die filling experiment was carried out using granulated MOX powder to investigate the condition of MOX granules suitable for constant die filling. It was found that the mean particle diameter and the Hausner ratio gave an indication of the die filling for the granulated MOX powder.

Development of simplified pelletizing process for fast reactor MOX fuels and demonstration experiment, 2; Die wall lubrication technology with using tumbling granular

Takato, Kiyoto; Nishina, Masahiro; Tsuchimochi, Ryota; Hayashizaki, Kohei; Segawa, Tomoomi; Kawaguchi, Koichi; Ishii, Katsunori; Makino, Takayoshi; Okumura, Kazuyuki

no journal, , 

no abstracts in English