Stabilizing Nuclear Waste with Glass and Ceramics
Engineering360 News Desk | November 14, 2016New approaches to the immobilization of radioactive waste are under development by an assistant professor at Rutgers University in New Jersey.
Techniques are being advanced to immobilize radioactive iodine in ceramics or glass at room temperature.
Glass produced from a high-level radioactive waste simulant.“Glass is a perfect material for immobilizing the radioactive wastes with excellent chemical durability,” says Ashutosh 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. With a half-life of 15.7 million years, iodine-129 can disperse rapidly and linger for millions of years if released into the environment.
One research project involves mass producing chemically durable apatite minerals, or glasses, to immobilize iodine without using high temperatures. A second innovation deploys synthesizing apatite minerals from silver iodide particles. The researcher also is studying how to immobilize sodium and alumina in high-level radioactive waste in borosilicate glasses that resist crystallization.
The U.S. Department of Energy, a funder of Goel’s investigations, continues to oversee cleanup of legacy waste from the nation's nuclear weapons production which once involved 16 major facilities. The Hanford site in Washington State represents one of the biggest cleanup challenges: about 56 million gallons of radioactive waste went to 177 large underground tanks. As many as 67 tanks are thought to have leaked, and the agency has pumped liquids out, leaving mostly dried solids.
Creating glass with radioactive waste at Hanford is expected to start in around 2022 or 2023, Goel says.
The research also may eventually lead to ways to safely dispose of highly radioactive spent nuclear fuel that is stored now at commercial nuclear power plants.