2022 Fiscal Year Final Research Report

The elucidation that is in chemistry form to investigate an environmental shift of fine particles emitted by Fukushima nuclear reactor accident

Research Project

PDF

Project/Area Number	18H04150
Research Category	Grant-in-Aid for Scientific Research (A)
Allocation Type	Single-year Grants
Section	一般
Review Section	Medium-sized Section 64:Environmental conservation measure and related fields
Research Institution	Kyoto University
Principal Investigator	Ohtsuki Tsutomu 京都大学, 複合原子力科学研究所, 特任教授 (50233193)
Co-Investigator(Kenkyū-buntansha)	関本俊京都大学, 複合原子力科学研究所, 助教 (10420407) 沖雄一京都大学, 複合原子力科学研究所, 准教授 (40204094) 高宮幸一京都大学, 複合原子力科学研究所, 准教授 (70324712) 篠原厚大阪大学, 理学研究科, 教授 (60183050) 末木啓介筑波大学, 数理物質系, 教授 (90187609)
Project Period (FY)	2018-04-01 – 2022-03-31
Keywords	原発事故 / 環境放射能 / 放射性微粒子 / 放射性エアロゾル / 核分裂生成物 / 廃炉
Outline of Final Research Achievements	We performed the generation experiments of radioactive fine particle and an outbreak experiments of the artificial radioactive aerosol to simulate the behavior of the radioactive fine particle and aerosol in a furnace of Fukushima Daiichi Nuclear Power Station (FDNPS). The elucidation of growth and transport mechanism of the radioactive particles (and aerosol) including plural nuclides in the FDNPS can be further investigated by the facts. Firstly, we performed analysis using SEM-EDX, the generation experiment of quasi fine particles has been performed to check the property of the radioactive fine particles emitted during environment. Then, we considered about the temperature dependence of generated quasi fine particles. Furthermore, we performed a simulation of growth and transportation of the artificial radioactive solution aerosol including fission products using the uranic dioxide which irradiated a neutron. Finally, we got the clue which supposed the situation in the FDNPS.
Free Research Field	放射化学
Academic Significance and Societal Importance of the Research Achievements	放射性微粒子の模擬生成実験や人工放射性エアロゾルの発生実験を行った。複数の放射性核種を含む微粒子やエアロゾルの成長・輸送機構の解明により1Fの炉内に残留する放射性微粒子の挙動を推測する手がかりを得た。環境中に放出された放射性微粒子の性状を調べるため、SEM-EDXを用いた分析をもとに模擬微粒子の生成実験を行い、生成される微粒子の加熱温度依存性について検討を行った。また、中性子照射した二酸化ウランを用いて、核分裂生成物を含む人工の放射性溶液エアロゾル粒子の成長・輸送の模擬実験を行った。これらの結果から実炉内の状況を推測し、廃炉に向けた作業等への知見を得た。