Did you know that bananas are radioactive?
Bananas contain a small amount of potassium-40, a naturally occurring radioactive isotope.
On August 24th, I absorbed 2 bananas’ worth of radiation when I toured McMaster University’s Nuclear Reactor at the 16th International Conference on Nuclear Fuel.
This conference brought together the world’s foremost experts on nuclear fuel design, fabrication, operation and safety analysis, highlighting advancements in CANDU and SMR fuel, and international reactor fuel cycles (PWR, BWR, etc.). I attended eye-opening industry talks in the morning, in-depth technical lectures in the afternoon, and finally a field trip to McMaster’s world-renowned electron microscopy lab (CCEM) and nuclear reactor (MNR).
Here’s what I took away from this incredible experience:
The world consumes 170,000 TWh of energy per year, with nuclear fission providing 9-10% of this number. A single pellet of uranium dioxide has the equivalent energy of 1000 kg of coal and 550 litres of oil. By obtaining energy from the nucleus instead of the electrons, nuclear fuel is 1,000,000 times more energy-dense than chemical fuels.
While nuclear fuel has an important role to play in world decarbonization, the industry faces some significant challenges:
Of all the elements on the periodic table, only three are capable of fission – thorium, plutonium, and uranium - and of these, only one isotope of uranium is naturally fissile, U-235.
The world is running out of U-235. Kazakhstan, the world’s largest producer - accounting for 40% of global supply - projects that its reserves will be significantly depleted by 2040. This poses a challenge to the global goal of tripling nuclear capacity by 2050, making the development of new uranium reserves essential to meeting the world’s nuclear energy ambitions.
Zirconium cladding is universal to all nuclear fuel types/cycles but faces significant geopolitical constraints. There is great interest in westernizing zirconium production, and this may include extraction in Canada’s Athabasca Basin.
In the United States, pressurized water reactors (PWRs) require lithium hydroxide to control coolant pH, however, domestic sources are limited. There is a push to replace lithium hydroxide with potassium hydroxide, and this is currently being trialed at Sequoyah Nuclear Plant in Tennessee.
Whether Canada should pursue domestic nuclear fuel enrichment to reduce reliance on natural U-235 is a hot topic, and is not currently addressed in Canada’s Federal Nuclear Energy Strategy. There is potential to recycle spent CANDU fuel, which is almost entirely U-238. Although U-238 is not fissile, it can capture neutrons in a fast-neutron reactor (FNR) to produce fissile plutonium-239. Canada has over 60,000 tonnes of spent CANDU fuel.
Canadian Nuclear Laboratories and McMaster University are leading the advancement of fuel assembly defect analysis, applying XCT and neutron imaging in NDE, and leveraging AI tools for visualization and analysis.
Finally, a few interesting facts about the McMaster Nuclear Reactor (MNR):
At 5MW, MNR is Canada’s most powerful research reactor and the only major neutron source in the country. Importantly, it produces approximately 60% of the world’s supply of iodine-125 for cancer brachytherapy.
Visiting the MNR is a fascinating experience. The open pool reactor design allows visitors a direct view of the core from above, and the distinctive blue glow of Cherenkov radiation.
Brittany Chyz,M.Eng., P.Eng., is a SR&ED Technology Manager at Copoint.
