Although there is debate about the safety and long-term trade-offs with nuclear energy, there is an undeniable creation of waste that needs dealt with. And it needs to be dealt with for thousands (and thousands) of years. Naturally occurring minerals are providing a guidepost of sorts for designing better isolation methods.
While there might be room for improvement on reducing the amount the waste, unrecyclable nuclear fuel must be safely stored. Since nuclear fuels tend to take a while to stabilize, the containment method has to stand the test of time as well. Current methods address the issue by encapsulating the waste in glass through a process known as vitrification.
Glass may seem like a pretty stable, inert material, but when talking about nuclear decay, the time line can be very, very long. Glass is not exceptionally stable in the long run. Glass, which is really a generic term,
This is where Kyle Brinkman of Clemson University and his research team come in. According to a Clemson News article, “The team’s research is focused on crystalline ceramic that will be based on naturally occurring minerals…” These minerals, such as hollandite (Ba(Mn4+6Mn3+2)O16), are more stable than glass and may help, “…broaden disposal options and lower storage and disposal costs.”
Although glass is a proven material, the crystalline ceramics may be an important improvement. Brinkman describes it this way, “Our project is to learn from these naturally occurring, naturally stable minerals and design crystal structures that mimic them to incorporate waste elements we want to store.” Due to their often complex chemistry, mimicking naturally minerals and their structures is no small task.
The three-year, $800,000 project is funded by the U.S. Department of Energy’s Nuclear Energy University Programs. South Carolina is a good fit, because it receives about half of its energy from nuclear generation. The project includes collaborators from Clemson, the University of South Carolina, the University of Connecticut and Savannah River National Laboratory as well.
The work emphasizes the importance of improving methods before they fail and looking toward nature for engineering advice; aspects that are worth observing in non-nuclear design too.
Image: Clemson University