Small modular reactors (SMRs) are considered the future of nuclear energy because they are smaller and more importantly, safer. Preserving that safety is a key priority for Western researchers Hamidreza Abdolvand and Samantha Gateman.
Abdolvand, Canada Research Chair in advanced materials for low-emission energies, and Gateman, the Nuclear Waste Management Organization (NWMO) Industrial Research Chair, have each been awarded more than $1 million for the next four years from the Natural Sciences and Engineering Research Council (NSERC) Alliance program and Natural Resources Canada (NSERC-NRCan) to fund research on developing safe production and used nuclear fuel storage for SMRs. These are advanced nuclear reactors that generate approximately one-third of the power capacity of traditional nuclear power reactors.
The Ontario government is currently building four SMRs at the Darlington Nuclear Station in Bowmanville, Ont. Expected to come online between 2034 and 2036, these new SMRs would produce a total 1,200 megawatts (MW) of electricity, equivalent to powering 1.2 million Ontario homes.
Samantha Gateman with an X-ray photoelectron spectrometer. (Jeff Renaud)
"About 60 per cent of electricity in Ontario already comes from nuclear reactors, which is close to 15 per cent of the electricity for all of Canada. Nuclear energy is here to stay and we need to ensure the safe disposal of the fuel once it is used," said Gateman, a chemistry professor and expert in electrochemistry and corrosion science.
Working with industry partners NWMO, Canadian Nuclear Laboratories (CNL), Atomic Energy of Canada Limited (AECL), Kinectrics and the University Network of Excellence in Nuclear Engineering (UNENE), Gateman, Surface Science Western (SSW) director Mark Biesinger, chemistry professor Jamie Noel and researchers from Queen's University will explore how different spent nuclear fuels from proposed SMR technologies will impact containers designed by NWMO to encapsulate nuclear waste at power plants, like Darlington.
"At Western, we hold expertise in corrosion and materials degradation and host many of the specialized tools and equipment needed to puzzle all the pieces together and really understand what is happening in terms of the long-term safety of disposing nuclear fuels," said Gateman.
New nuclear fuel, new questions
While Gateman and her collaborators investigate the long-term safety of used nuclear fuel, Abdolvand and co-investigator Robert Klassen, a Western mechanical and materials engineering professor, will target the safe short-term, real-time use of tri-structural-isotropic (TRISO) fuel particles in SMRs. Used traditionally in the core of high temperature gas cooled nuclear reactors, TRISO fuel particles are made up of uranium, carbon and oxygen fuel kernels. The kernels are encapsulated by different layers of carbon- and ceramic-based materials that prevent the release of radioactive fission products.
The four-year project, led by Abdolvand and Klassen, in partnership with CNL, focuses on understanding the micromechanics of deformation and fracturing of surrogate TRISO. A surrogate is needed to replace the uranium component, which is the radioactive element of the kernel.
"TRISO fuels, the way that they are designed for SMRs, are inherently safe. At least, this is the expectation," said Abdolvand, a Western mechanical and materials engineering professor and an expert in deformation and failure of materials. "But the question is, how safe? This is what we want to see and test, as mechanical engineers. At which temperature will the protective casing deform and fracture because the ranges in SMRs are quite wide."
Hamidreza Abdolvand with a scanning electron microscope (SEM), which produces images of a sample by scanning the surface with a focused beam of electrons. (Jeff Renaud)
It is expected that the computer model and experimental data collected in the project will lead to a better understanding of the effects of thermomechanical loads on the safety and integrity of TRISO fuels.
