JOPSS - Search Results

Journal Articles

Revaporization behavior of cesium and iodine compounds from their deposits in the steam-boron atmosphere

Rizaal, M.; Miwa, Shuhei; Suzuki, Eriko; Imoto, Jumpei; Osaka, Masahiko; Goullo, M.*

ACS Omega (Internet), 6(48), p.32695 - 32708, 2021/12

https://doi.org/10.1021/acsomega.1c04441

Times Cited Count：6 Percentile：24.18(Chemistry, Multidisciplinary)

Journal Articles

Chemical forms of uranium evaluated by thermodynamic calculation associated with distribution of core materials in the damaged reactor pressure vessel

Ikeuchi, Hirotomo; Yano, Kimihiko; Washiya, Tadahiro

Journal of Nuclear Science and Technology, 57(6), p.704 - 718, 2020/06

https://doi.org/10.1080/00223131.2020.1720844

Times Cited Count：8 Percentile：48.65(Nuclear Science & Technology)

To suggest efficient process of the fuel debris treatment after the retrieval from the Fukushima Daiichi Nuclear Power Plant (1F), thorough investigation is indispensable on potential source of U in the fuel debris. Estimation on the fuel debris accumulated in the reactor pressure vessel is specifically important due to its limited accessibility. The present study aims to estimate the chemical forms of U in the in-vessel fuel debris, especially in the minor phases such as metallic phases, by performing the thermodynamic calculation considering the material relocation and changing environment during the accident progression in the 1F Unit 2. Input conditions for the thermodynamic calculation such as composition, temperature, and oxygen amount were assumed mainly based on the results of severe accident analysis. The chemical form of U varied depending on the local amount of Fe and O. In regions of low steel content, the U-containing metallic phase was dominated by -(Zr,U)(O), while regions of high steel content were dominated by Fe $_{2}$ (Zr,U) (Laves phase). A few percent of U was transferred to the metallic phases under reducing conditions, raising challenging issues on the chemical removal of nuclear material from fuel debris.

Journal Articles

Thermodynamic evaluation of the solidification phase of molten core-concrete under estimated Fukushima Daiichi Nuclear Power Plant accident conditions

Kitagaki, Toru; Yano, Kimihiko; Ogino, Hideki; Washiya, Tadahiro

Journal of Nuclear Materials, 486, p.206 - 215, 2017/04

AA2016-0278.pdf:0.74MB

https://doi.org/10.1016/j.jnucmat.2017.01.032

Times Cited Count：38 Percentile：94.31(Materials Science, Multidisciplinary)

JAEA Reports

Research on treatment and disposal of RI and research institute waste; Progress in Department of Fuel Cycle Safety Research

Department of Fuel Cycle Safety Research

JAERI-Review 2001-019, 108 Pages, 2001/07

JAERI-Review-2001-019.pdf:6.04MB

Department of Fuel Cycle Safety Research, JAERI, has been carrying out research on safe and rational disposal systems of radioactive wastes arising from medical activities and research institutes (RI and Research Institute Waste). The research area includes a study on molten solidified waste form, a geological survey on Japan, a proposal on integrated disposal systems, data acquisition for safety evaluation, and a safety analysis of disposal systems. This report introduces progress and future works for the treatment and disposal of RI and Research Institute Waste.

Journal Articles