Vitrification of Low-Activity Radioactive Waste Streams and a High-Level Radioactive Waste Stream in Support of the Hanford River Protection Program

Conference · Wed Jul 10 04:00:00 EDT 2002

OSTI ID:799421

Crawford, C L

Hanford tank waste consists of about 190 million curies in 54 million gallons of highly radioactive and mixed hazardous waste stored in underground storage tanks at the Hanford Site in Washington State. The tank waste includes solids (sludge), liquids (supernatant), and salt cake (dried salts that dissolve in water to form supernatant). The tank waste will be remediated through treatment and immobilization to protect the environment and meet regulatory requirements. The U.S. Department of Energy's (DOE's) preferred alternative to remediate the Hanford tank waste is to pretreat the waste by separating it into low-activity waste (LAW) and high-level waste (HLW), followed by immobilization of the LAW for on-site disposal and immobilization of the HLW for ultimate disposal in a national repository. This paper describes the crucible-scale vitrification and associated wasteform product tests in support of the WTP at Hanford. The two different LAW glasses produced in this study were from pretreated Envelope A (Tank 241-AN-103) and Envelope C (Tank 241-AN-102) waste. The HLW glass was produced from Tank C-106 HLW sludge and the HLW radionuclide products separated from Hanford Site tank samples AN-103, AN-102 and AZ-102. Pretreatment of these three supernates consisted of characterization, strontium and transuranics removal by precipitation and filtration, and final Cs-137 and Tc-99 removal by ion exchange (IX). The glasses were produced from formulations supplied by Vitreous State Laboratory of the Catholic University of America (CUA). Formulations were based on previous surrogate testing and the actual characterization data from the radioactive feed streams. Crucible-scale vitrifications were performed in platinum/gold crucibles in a custom-designed furnace fit with an offgas containment system. Both LAW and HLW melter feed slurries were evaporated, calcined, and then melted at 1150 degrees C. The LAW and HLW glasses were heat-treated per a modeled centerline cooling curve for the LAW canister and HLW canister, respectively.

• Research Organization: Savannah River Site (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: AC09-96SR18500
• OSTI ID: 799421
• Report Number(s): WSRC-MS-2002-00449
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
CONTAINERS
CONTAINMENT SYSTEMS
HIGH-LEVEL RADIOACTIVE WASTES
ION EXCHANGE
RADIOACTIVE WASTES
RADIOISOTOPES
RIVERS
SLUDGES
UNDERGROUND STORAGE
VITRIFICATION
WASTE FORMS
WASTES