FUKUSHIMA DAI-ICHI FUEL DEBRIS RETRIEVAL: AEROSOL POOL SCRUBBING EFFICIENCY APPLIED TO UNDERWATER LASER CUTTING

Abstract

The general context of the article is related to the development of the laser cutting technique for the fuel debris retrieval on the damaged reactors of Fukushima Dai-ichi. IRSN and CEA are involved in a project, led by ONET Technologies, to develop technologies for fuel debris retrieval and to bring relevant elements to analyze the risk occurred by the dispersion of aerosols emitted by the dismantling operations. Results regarding the characterization of the aerosols source term emitted during laser cutting of non-radioactive fuel debris simulants were acquired during experiments undertaken in the DELIA cutting laser platform from CEA. IRSN realized aerosol sampling, aerosol size distribution measurement and evaluation of aerosols collection efficiency versus water level. The performed evaluations will enable the Japanese teams responsible for retrieving fuel debris or corium from the damaged reactors of Fukushima Dai-ichi to define the best strategies to implement containment, and ultimately to limit the dissemination of radionuclides into the environment.