Technical Basis for Eliminating Carbon-14 As A Reportable Radionuclide in DWPF Glass

NED, BIBLER

Savannah River Site (S.C.)

关键词: Sludges;    Oxides;    Specifications;    Processing;    Carbon 14;   

DOI  :  10.2172/838802
RP-ID  :  WSRC-TR-2004-00629
RP-ID  :  AC09-96SR18500
RP-ID  :  838802

美国|英语

来源: UNT Digital Library

【 摘 要 】

The Defense Waste Process Facility, DWPF, of Savannah River Site, SRS, is immobilizing the High Level Waste, HLW, sludges at SRS into a borosilicate glass for geologic disposal in a repository. In order for the glass to be acceptable to the repository, a set of acceptance specifications have been written. These are published as the ''Waste Acceptance Product Specifications, WAPS, for Vitrified High-Level Waste Forms.'' Specification 1.2 of the WAPS requires that, ''The Producer shall report the inventory of radionuclides (in Curies) that have half-lives longer than 10 years and that are, or will be, present in concentrations greater than 0.05 percent of the total inventory for each waste type indexed to the years 2015 and 3115''. As part of the strategy developed to meet Specification 1.2, the DWPF elected to report for each waste type, all radionuclides with half-lives greater than 10 years that have concentrations greater than 0.01 percent of the total inventory from time of production through the 1100 year period from 2015 through 3115. For the sludge batches processed thus far by the DWPF, either 26 or 27 radionuclides have been identified as reportable in the first three sludge batches. One of these radionuclides is carbon-14. This report presents results of an investigation to determine if carbon and thus the carbon-14 would survive DWPF processing and be reportable in DWPF glass. Based on a thorough literature review, a review of process knowledge, and the expected chemistry of carbon in the DWPF process, we conclude all chemical forms of carbon in SRS HLW are converted to gaseous oxides during DWPF processing. Thus carbon-14 would not be a reportable component of the final HLW glass.