JOPSS - Search Results

Search Results: Records 1-20 displayed on this page of 25

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Journal Articles

Flexible fuel cycle system for the effective management of plutonium

Fukasawa, Tetsuo*; Hoshino, Kuniyoshi*; Yamashita, Junichi*; Takano, Masahide

Journal of Nuclear Science and Technology, 57(11), p.1215 - 1222, 2020/11

https://doi.org/10.1080/00223131.2020.1779144

Times Cited Count：1 Percentile：9.26(Nuclear Science & Technology)

The flexible fuel cycle initiative system (FFCI system) has been developed to reduce spent fuel (SF) amounts, to keep high availability factor for the reprocessing plant and to increase the proliferation resistance for the recovered Pu. The system separates most U from the SF at first, and the residual material called recycle material (RM) which contains Pu, minor actinides, fission products and remaining U will go to Pu(+U) recovery from the RM for Pu utilizing reactor in future. The Pu utilizing reactor is FBR or LWR with MOX fuel. The RM is the buffer material between SF reprocessing and Pu utilizing reactor with compact size and high proliferation resistance, which can suppress the amount of relatively pure Pu. The innovative technologies of FFCI are most U separation and temporary RM storage. They are investigated by the literature survey, fundamental experiments using simulated material and analyses using simulation code. This paper summarizes the feasibility confirmation results of FFCI.

Journal Articles

Fundamental study on segregation behavior in U-Zr-Fe-O system during solidification process

Sudo, Ayako; Mizusako, Fumiki*; Hoshino, Kuniyoshi*; Sato, Takumi; Nagae, Yuji; Kurata, Masaki

Nihon Genshiryoku Gakkai Wabun Rombunshi, 18(3), p.111 - 118, 2019/08

https://doi.org/10.3327/taesj.J18.029

Cooling rate of molten core materials during solidification significantly affects the segregation of major constituents of fuel debris. To understand general tendency of the segregation, liquefaction/solidification tests of simulated corium (UO $_{2}$ , ZrO $_{2}$ , FeO, B $_{4}$ C and sim-FP oxides) were performed. Simulated corium was heated up to 2600 $^{circ}$ C under Ar atmosphere and then cooled down with two different cooling processes; furnace cooling (average cooling rate is approximately 744 $^{circ}$ C/min) and slow cooling (cooling rate in 2600 $^{circ}$ C2300 $^{circ}$ C is 5 $^{circ}$ C/min and in 2300 $^{circ}$ C1120 $^{circ}$ C is approximately 788 $^{circ}$ C/min). Element analysis detected three oxide phases with different composition and one metal phase in both solidified samples. Solubility of FeO in these oxide phases was mostly fixed to be 125at% in both samples, which is in reasonable accordance with the value estimated from UO $_{2}$ -ZrO $_{2}$ -FeO phase diagrams. However, a significant grain-growth of one oxide phase, rich in Zr-oxide, was detected only in the slowly cooled sample. The composition of this particular oxide phase is comparable to the initial average composition. The condensation is considered to be caused by the connection of remaining liquid agglomerates during slow solidification.

Journal Articles

Corium stratification test using intermediate products of degraded core materials in severe accident of BWR

Tokushima, Kazuyuki; Shirasu, Noriko; Hoshino, Kuniyoshi*; Ohara, Hiroshi*; Kurata, Masaki

Proceedings of Annual Topical Meeting on LWR Fuels with Enhanced Safety and Performance (TopFuel 2016) (USB Flash Drive), p.1055 - 1063, 2016/09

At the fuel assembly degradation stage in severe accidents, chemical features of the intermediate products are expected to be changed depending upon the accident progressions. These differences are originated from the differences in oxygen potential and temperature, and are highly important for evaluating the relocation and stratification progress of the fuel debris. Two types of sim-test with the different oxygen potentials were performed to investigate these tendencies. The chemical features of the intermediate materials used in the tests were determined from the observations for the control blade and channel box degradation in our previous study. The present results indicate that the U concentration in the metallic layer is largely varied depending upon the oxygen potential of the atmosphere. Also, when the B $_{4}$ C-Fe alloy, as of a typical intermediate product, coexists with UO $_{2}$ and Zr, the apparent red-ox reaction rate between UO $_{2}$ and Zr are mitigated.

Journal Articles

Controls of chromium and third element contents in nickel-base alloys for corrosion resistant alloys in hot HNO-HF mixtures

Takeuchi, Masayuki; Nakajima, Yasuo; Hoshino, Kuniyoshi*; Kawamura, Fumio*

Journal of Alloys and Compounds, 506(1), p.194 - 200, 2010/09

https://doi.org/10.1016/j.jallcom.2010.06.175

Times Cited Count：10 Percentile：47.60(Chemistry, Physical)

Journal Articles

Flexible fuel cycle R&D for the smooth FBR deployment

Fukasawa, Tetsuo*; Yamashita, Junichi*; Hoshino, Kuniyoshi*; Sasahira, Akira*; Inoue, Tadashi*; Minato, Kazuo; Sato, Seichi*

Proceedings of 16th Pacific Basin Nuclear Conference (PBNC-16) (CD-ROM), 6 Pages, 2008/10

Transition period from light water reactors (LWR) to fast breeder reactors (FBR) is quite important to achieve the future FBR cycle system. The transition scenarios were carefully studied and the Flexible Fuel Cycle Initiative (FFCI) was proposed in this study. FFCI carries out about 90% uranium (U) removal from LWR spent fuels (SF) at first and then recovers plutonium/uranium (Pu/U) from the remaining SF named "recycle material"(RM) (about 40% U, 15% Pu and 45% other nuclides) for FBR fresh fuel fabrication according to the FBR deployment status. The FFCI has some merits compared with ordinary system that carries out full reprocessing of LWR SF, that is volume reduction of LWR SF by its conversion to RM (proliferation resistant material), and storage and supply of high Pu density RM according to FBR deployment rate changes.

Journal Articles

Uranium recovery in LWR reprocessing and plutonium/residual uranium conditioning in FBR reprocessing for the transition from LWR to FBR

Fukasawa, Tetsuo*; Yamashita, Junichi*; Hoshino, Kuniyoshi*; Sasahira, Akira*; Inoue, Tadashi*; Minato, Kazuo; Sato, Seichi*

Proceedings of 3rd International ATALANTE Conference (ATALANTE 2008) (CD-ROM), 7 Pages, 2008/05

In order to flexibly manage the transition period from LWR to FBR, the authors investigated the transition scenario and proposed the Flexible Fuel Cycle Initiative (FFCI). In FFCI, LWR spent fuel reprocessing only carries out the removal of about 90% uranium that will be purified and utilized in LWR after re-enrichment. The residual material (40% U, 15% Pu and 45% other nuclides) is transferred to temporary storage and/or FBR spent fuel reprocessing to recover Pu/U followed by FBR fresh fuel fabrication depending on the FBR introduction status. The FFCI has some merits compared with ordinary system that consists of full reprocessing facilities for both LWR and FBR spent fuels, that is smaller LWR reprocessing facility, spent LWR fuel reduction, storage and supply of high proliferation resistant and high Pu density material that can flexibly respond to FBR introduction rate changes. The Pu balance was calculated under several cases, which revealed that the FFCI could supply enough Pu to FBR in any cases.

JAEA Reports

Investigation of Conceptua1 Facility Structure on the vibration packing fuel manufacturing system Corresponding to wet fuel recycle plant

Kawamura, Fumio*; Aoi, Masakatsu*; Hoshino, Kuniyoshi*

JNC TJ9420 2003-006, 436 Pages, 2004/02

JNC-TJ9420-2003-006.pdf:3.67MB

The stratagem feasibility studies for aim of commercialization of FBR cycle system have been researched in JNC. In these studies economy, load suppression for environmentality, non-proliferation and et. al. have been evaluated for several kinds of systems. In series of these researches, we had researched the vibration packing fuel manufacturing system of wet fuel recycle plant for FBR's fuel, and investigated the concepts of main equipments for the fuel pin fabrication system. In 2002 we had achieved the conceptual design of main equipments and assignment of those in cells from reception process of fuel particles material to storage process of fuel assemblies concerning the production scale about 50t-HM/y manufacturing system, and estimated the applicability of fabrication system in cell. In this study, we have researched the conceptual design and assignment in cells of main equipments of the vibration packing fuel manufacturing system, quality control, and maintenance of equipments concerning the production scale about 200t-HM/y manufacturing system. The building is constructed independently near here the recycle facility building and fuel particle fabrication building. And then the technical matching and economical evaluation of manufacturing system have been investigated. Resulting these investigations, we have got the basic conceptual design of main equipments for the fuel pin fabrication system in the scale of 200t-HM/y, assignment of main procedure cell and auxiliary equipments, and also the ability of 200 days operation per year based on the quality control and maintenance of equipments. And then we have got the aspect of technical matching to the plant and the reasonable economical evaluation of manufacturing system. It is cleared that this manufacturing method is the suitable one of systems concerning of wet fuel recycle plant for FBR's fuel manufacturing system.

Oral presentation