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.

Development of wet process with substitution reaction for the mass production of LiTiO pebbles

Tsuchiya, Kunihiko; Kawamura, Hiroshi

Journal of Nuclear Materials, 283-287(Part.2), p.1380 - 1384, 2000/12

https://doi.org/10.1016/S0022-3115(00)00099-4

no abstracts in English

Mass fabrication development of LiTiO pebbles with automatic dropping system

Tsuchiya, Kunihiko; Kawamura, Hiroshi; ; ;

Fusion Technology 1998, 2, p.1293 - 1296, 1998/00

no abstracts in English

Fabrication development of LiO pebbles by wet process

Tsuchiya, Kunihiko; Saito, Shigeru; Kawamura, Hiroshi; ; ;

Journal of Nuclear Materials, 253, p.196 - 202, 1998/00

https://doi.org/10.1016/S0022-3115(97)00312-7

no abstracts in English

Analysis of metallic salt granulation preocess, II

Tokuoka, Naochika*; Kobayashi, Mamoru*; Koyama, Takashi*

PNC TJ1636 96-001, 64 Pages, 1996/03

PNC-TJ1636-96-001.pdf:14.63MB

None

Characteristics of LiO pebbles fabricated by the melting granulation method

; Kawamura, Hiroshi; Nakamichi, Masaru; Imaizumi, Hideki*; Saito, Minoru; ; Nagakura, Masaaki*

Journal of Nuclear Materials, 219, p.240 - 245, 1995/00

https://doi.org/10.1016/0022-3115(94)00531-1

no abstracts in English

Evaluation of the effects of granulated alumina powder characteristics and die wall lubricant on compaction behavior using X-ray computed tomography

Segawa, Tomoomi; Kawaguchi, Koichi; Ishii, Katsunori; Nishina, Masahiro; Makino, Takayoshi; Iimura, Kenji*; Satone, Hiroshi*; Suzuki, Michitaka*; Natori, Yuri*

no journal, , 

Japan Atomic Energy Agency has developed a simplified pelletizing fuel fabrication system. In this system, the flowability of a MOX raw powder is improved by wet granulation for the pelletizing process, and the die wall lubrication method directly presses the granulated MOX powder into green pellets without adding any lubricant into the powder. The homogeneous compression is important to fabricate high-density green pellets. However, it is difficult to observe the compaction behavior in situ. Therefore, the capping phenomenon was investigated by using X-ray computed tomography and alumina powder that is highly transparent against X-rays. When lubricant was used, the breakage of the particles extended to the bottom compared with not used. This result indicates that the die wall lubrication is effective for the homogeneous compression of granulated powders.

Study on development of additive-free dry granulation technology and evaluation of granulation characteristics

Ishii, Katsunori; Segawa, Tomoomi; Kawaguchi, Koichi; Nishina, Masahiro; Makino, Takayoshi; Natori, Yuri*

no journal, , 

JAEA is developing simplified a plutonium and uranium mixed oxide (MOX) pellet fabrication process. In this process, agitation granulator improves flowability of MOX powder with water as binder. This granulation method has issues, including low production capacity due to criticality control for wet nuclear material. A new simple additive-free dry granulation method was proposed recently to produce tritium breeding LiO spheres for nuclear fusion reactor. In this research, results of experiments to investigate the applicability of the new granulation method to MOX powder is reported.

Unconfined compression strength of tamlbing granular by DEM simulation

Akashi, Masatoshi; Kato, Masato; Tamura, Tetsuya*

no journal, , 

no abstracts in English

Drying experiments of CeO granules produced using wet granulator

Ishii, Katsunori; Segawa, Tomoomi; Kawaguchi, Koichi

no journal, , 

The Japan Atomic Energy Agency is developing a simplified mixed oxide (MOX) fuel fabrication process. In this process, a wet granulator improves the flowability of MOX raw powder for the pelletizing process 1, 2). Following this granulation step, the formed granules have moisture content of approximately 10 wt.%. To adhere to the acceptance standards regarding moisture content for the fuel pellet fabrication step, drying the granules under the moisture content of 1 wt.% using a dryer is necessary. To maintain the granule shape during powder handling and shaker process of a pressing machine, the granules must be adjusted to enough crushing strength. However, the relation between dry conditions and granule crushing strength has not been reported. Therefore, to estimate the appropriate heating conditions of the dryer, we investigated the influence of varying heating conditions on moisture content and granule crushing strength.