Development and testing of matrices for the encapsulation of glass and ceramic nuclear waste forms.

Technical Report · Mon Feb 01 04:00:00 EST 1982

DOI:https://doi.org/10.2172/5421190· OSTI ID:5421190

Wald, J W; Brite, D W; Gurwell, W E; Buckwalter, C Q; Bunnell, L R; Gray, W J; Blair, H T; Rusin, J M

This report details the results of research on the matrix encapsulation of high level wastes at PML over the past few years. The demonstrations and tests described were designed to illustrate how the waste materials are effected when encapsulated in an inert matrix. Candidate materials evaluated for potential use as matrices for encapslation of pelletized ceramics or glass marbles were categorized into four groups: metals, glasses, ceramics, and graphite. Two processing techniques, casting and hot pressing, were investigated as the most promising methods of formation or densification of the matrices. The major results reported deal with the development aspects. However, chemical durability tests (leach tests) of the matrix materials themselves and matrix-waste form composites are also reported. Matrix waste forms can provide a low porosity, waste-free barrier resulting in increased leach protection, higher impact strength and improved thermal conductivity compared to unencapsulated glass or ceramic waste materials. Glass marbles encapsulated in a lead matrix offer the most significant improvement in waste form stability of all combinations evaluated. This form represents a readily demonstrable process that provides high thermal conductivity, mechanical shock resistance, radiation shielding and increased chemical durability through both a chemical passivation mechanism and as a physical barrier. Other durable matrix waste forms evaluated, applicable primarily to ceramic pellets, involved hot-pressed titanium or TiO/sub 2/ materials. In the processing of these forms, near 100% dense matrices were obtained. The matrix materials had excellent compatibility with the waste materials and superior potential chemical durability. Cracking of the hot-pressed ceramic matrix forms, in general, prevented the realization of their optimum properties.

• Research Organization: Pacific Northwest Lab., Richland, WA (USA)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 5421190
• Report Number(s): PNL-4098; ON: DE82008774
• Country of Publication: United States
• Language: English

Related Subjects

052001* -- Nuclear Fuels-- Waste Processing
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
ALUMINIUM
BUILDING MATERIALS
CARBON
CASTING
CEMENTS
CERAMICS
CHALCOGENIDES
COMPARATIVE EVALUATIONS
DATA
DISSOLUTION
ELEMENTAL MINERALS
ELEMENTS
ENCAPSULATION
EXPERIMENTAL DATA
FABRICATION
GLASS
GRAPHITE
HIGH-LEVEL RADIOACTIVE WASTES
HOT PRESSING
INFORMATION
LEACHING
LEAD
MANAGEMENT
MATERIALS
MATERIALS WORKING
MATRIX MATERIALS
METALS
MINERALS
NONMETALS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PRESSING
PROCESSING
RADIOACTIVE MATERIALS
RADIOACTIVE WASTE PROCESSING
RADIOACTIVE WASTES
SEPARATION PROCESSES
TIN
TITANIUM
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
VANADIUM
WASTE MANAGEMENT
WASTE PROCESSING
WASTES
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES