This scaled-down vitrification plant at the Pacific Northwest National Laboratory is being commissioned to test various waste glass components and configurations.
RICHLAND, Wash. — For more than a decade, the U.S. Department of Energy Office of Environmental Management’s Office of River Protection has collaborated with national and international laboratories, universities and glass industry experts to plan and prepare for 24/7 operations at the Waste Treatment and Immobilization Plant (WTP) at the Hanford Site.
When operational, WTP will begin vitrifying millions of gallons of radioactive and chemical waste stored in Hanford’s large, underground tanks since national defense operations during World War II and the Cold War era. Vitrifying the waste entails immobilizing it in glass through mixing in large melters.
When cooled, the waste components do not sit inside the glass, rather they become part of the glass itself, chemically bound in place for safe disposal.
The waste treatment preparations include work by experts in national facilities: Pacific Northwest National Laboratory (PNNL) in Richland, Washington; Idaho National Laboratory in Idaho Falls; the Vitreous State Laboratory in Washington, D.C.; and Savannah River National Laboratory in Aiken, South Carolina. The international counterparts include universities in England and the Czech Republic, colleagues in Sweden and Israel, and institutes in France and Japan.
Over the years, the national labs have developed a large database of glass properties, from which PNNL has built chemical-property models and a glass-formulation program to run the vitrification process more efficiently. In addition, Rutgers University, Washington State University – Pullman and Sheffield Hallam University in England have contributed through studying the structure of glass and how it can be used to control the properties of various wastes.
The University of Chemistry and Technology in Prague has contributed through testing how various waste streams are fed to melters, and scientists in Israel, Sweden and England have studied waste glass durability and how it compares to that of naturally occurring glasses that have existed in the environment for thousands of years.
In addition, communication with Corning Inc., formerly Corning Glass Works, ensures alignment with current industrial glass manufacturing developments, and discussions with counterparts in France and Japan help ensure correlation with similar research where technologies, waste streams and immobilization strategies differ slightly.
The international effort has been instrumental in helping Hanford anticipate and address engineering and operational challenges to immobilize waste in glass. PNNL, the lab closest to WTP and directly connected to the Hanford Site, has been the integrator of the effort, maintaining the largest staff, a diverse array of laboratory equipment and several key testing platforms.
-Contributor: Albert Kruger
-Source: EM Update Newsletter