Address:
Mr Hugo Leffolley from Subatech laboratoy, will present his research about :
"Synthèse de microparticules de silicates riches en césium par interaction de combustible en fusion avec du béton : simulation expérimentale de phénomènes présents lors de l’accident de Fukushima Daiichi"
On March 11, 2011, a powerful earthquake and tsunami caused the nuclear accident at the Fukushima Daiichi power plant in Japan. During the course of the accident, radioactive releases occurred towards the land in Japan and into the Pacific Ocean. Among these radioactive releases, Cs-bearing microparticles (CsMP) of amorphous silica were identified as a significant pollution source. This unprecedented form of radioactive pollution is highly insoluble, and its behavior in the environment could be significantly different from previously anticipated forms of cesium releases. Several hypotheses have been put forward by the scientific community to explain the process of their formation. This aspect holds significant importance in enhancing our comprehension of the accident's progression and assessing the necessity of considering them within the source term of a hypothetical future incident. An experiment aiming to reproduce a small-scale corium-concrete interaction has been conducted and has confirmed that this phenomenon is capable of producing CsMP. A detailed analysis of the experimental aerosols revealed the presence of micrometer-sized and nanometer-sized particles, with similar chemical composition, consisting of an amorphous silica matrix and containing nano-inclusions. Finally, a generation mechanism has been suggested to explain the origin of CsMP.
Organizer(s)
Thesis acreditation from IMT Atlantique with the Doctoral School 3MG
Keywords : CsMP, radioactive aerosols, Fukushima Daiichi, corium, caesium