When nuclear fuel at a power plant is used up, the assemblies that hold it are placed in pools of circulating water and left to cool for years. But the fuel remains extremely hot – several hundred degrees Fahrenheit – extremely radioactive and extremely dangerous. After the fuel assemblies, each made up of multiple fuel rods filled with tiny pellets of uranium, cool to a required level, they are placed in a canister or cask while still underwater. The water is pumped out and helium, an inert gas, is injected. Then the canisters are taken to a temporary storage area, either above or slightly below ground and usually near the power plant, since there’s still no permanent location to store spent nuclear fuel. Unfortunately, once the casks are sealed, it’s nearly impossible to see what’s going on inside. Scientists there have built a simulated dry cask – complete with a 14-foot-long mock nuclear fuel assembly hooked up to 700 thermocouples – devices that measure temperature. While real-life casks are capable of holding 68 to 89 fuel assemblies, the Sandia simulation is just using one. Modelers can then extrapolate the data.
Albuquerque Journal 28th July 2018 read more »
Can Radioactive Waste Be Immobilized in Glass for Millions of Years? How do you handle nuclear waste that will be radioactive for millions of years, keeping it from harming people and the environment? It isn’t easy, but Rutgers researcher Ashutosh Goel has discovered ways to immobilize such waste — the offshoot of decades of nuclear weapons production — in glass and ceramics. Goel, an assistant professor in the Department of Materials Science and Engineering, is the primary inventor of a new method to immobilize radioactive iodine in ceramics at room temperature. He’s also the principal investigator (PI) or co-PI for six glass-related research projects totaling $6.34 million in federal and private funding, with $3.335 million going to Rutgers. “Glass is a perfect material for immobilizing the radioactive wastes with excellent chemical durability,” said Goel, who works in the School of Engineering. Developing ways to immobilize iodine-129, which is especially troublesome, is crucial for its safe storage and disposal in underground geological formations.
Geology In 29th July 2018 read more »