Kärnkraftsbränslen

Kärnkraftsbränslen, or nuclear fuels, are materials used in nuclear reactors to sustain a controlled nuclear chain reaction. The most common type of nuclear fuel is uranium-235, an isotope of uranium that is fissile, meaning it can sustain a chain reaction. Uranium-235 is typically enriched from natural uranium, which contains only about 0.7% of this isotope. The enriched uranium is then processed into fuel pellets, which are stacked into fuel rods and assembled into fuel assemblies.

Another type of nuclear fuel is plutonium-239, which is produced from uranium-238 through neutron capture and subsequent beta decay. Plutonium-239 is also fissile and can be used as a fuel in nuclear reactors. Mixed oxide (MOX) fuel, which contains a blend of uranium oxide and plutonium oxide, is another type of nuclear fuel used in some reactors.

Nuclear fuels are characterized by their burnup, which is the amount of energy produced per unit mass of fuel. The burnup of a fuel assembly is typically measured in megawatt-days per metric ton of uranium (MWd/MTU). The higher the burnup, the more efficiently the fuel is used, but it also leads to the accumulation of fission products, which can affect the performance of the reactor.

The safety and environmental impact of nuclear fuels are significant considerations in their use. Proper management of spent nuclear fuel, including its storage and disposal, is crucial to minimize risks to human health and the environment. Research and development efforts are ongoing to improve the safety and efficiency of nuclear fuels and to find alternative fuels that could reduce reliance on fissile materials.