Iodine chemistry

During an accident in a nuclear facility, radionuclides resulting from the fission of the fuel are likely to be released into the environment. Iodine is a particularly important fission product because it contributes significantly to the radiological consequences. The research conducted aims to model the impact of radioactive iodine with a small-scale model. Thanks to previous joint IRSN/University of Lille work undertaken in the framework of the former C3R Joint Research Laboratory (LRC) on the one hand, and the new mechanism of iodine in the gas phase discovered during Camille Fortin's doctoral thesis on the other, the simulations will allow a better understanding of the impact of atmospheric iodine releases following the Fukushima-Daiichi accident on ozone and air pollution.

The study proposed here focuses on modeling the Fukushima-Daiichi accident during the entire duration, using the different source terms estimated in the literature. Thanks to the patterns highlighted by the 0D study performed by Camille Fortin, the detailed chemical mechanism will then be reduced. Once this step has been completed, IRSN will be able to incorporate the results of this study into the models implemented in its fast tools, allowing the description of the behavior of iodine in the atmosphere, both in the near and far fields.