The safe retrieval and storage of nuclear fuel debris, such as that generated by the Fukushima-Daiichi nuclear power plant accident 10 years ago, requires an understanding of the behaviour of these debris while being stored and processed. Bulk scale studies have been conducted which have yielded understanding of the characteristics of these debris at the larger scales. However, it has been noted that the processing of these debris generates micro- and nano-scale particles, particularly in the 1 to 100 nm scales. These particles are in solution and may be present in aerosols generated by the processing such as cutting with mechanical or laser means. Importantly, the particles at these scales behave differently than particles at larger scales. This difference in behaviour must be understood to be able to predict their behaviour while being processed.
This project brings together experimental expertise, both in the UK and Japan, as well as expertise in the development and use of mathematical modelling to develop the experimental and mathematical tools necessary to ensure safe processing of the debris. The experimental expertise includes characterisation capabilities for structure and surface properties of the particles and for the dynamic behaviour of the particles in solutions in microfluidic channels, including dissolution, denaturation, and aggregation/agglomeration. The resources and expertise of the labs at UCL and Tokyo Institute of Technology are complementary. The mathematical expertise at UCL is also well aligned with the experimental capabilities, demonstrated through previous successful collaborative projects.