ALLOY WASTE FORMS FOR MEATL FISSION PRODUCTS AND ACTINIDES ISOLATED BY SPENT NUCLEAR FUEL TREATMENT

摘要

Waste form alloys are being developed at ArgonneNational Laboratory for the disposal of remnant metallic wastesfrom an electrometallurgical process developed to treat spentnuclear fuel. This metal waste form consists of the fuel cladding(stainless steel or Zircaloy), noble metal fission products (e.g.,Ru, Pd, Mo and Tc), and other metallic wastes. The mainconstituents of the metal waste stream are the cladding hulls (85to 90 wt percent); using the hulls as the dominant alloyingcomponent minimizes the overall waste volume as compared tovitrification or metal encapsulation. Two nominal compositionsfor the waste form are being developed: (1) stainless steel-l 5 wtpercent zirconium for stainless steel-clad fuels and (2)zirconium-8 wt percent stainless steel for Zircaloy-clad fuels.The noble metal fission products are the primary source ofradiation in the metal waste form. However, inclusion ofactinides in the metal waste form is being investigated as anoption for interim or ultimate storage. Simulated waste formalloys were prepared and analyzed to determine the baselinealloy microstructures and the microstructural distribution ofnoble metals and actinides. Corrosion tests of the metal wasteform alloys indicate that they are highly resistant to corrosion.