Analysis of Sludge Batch 3 (Macrobatch4) DWPF Pour Stream Glass Sample for Canister s02312

Bannochie, C

Savannah River Site (S.C.)

关键词: Sludges;    Radioactive Waste Processing;    Waste Forms;    Density;    Chemical Composition;   

DOI  :  10.2172/890195
RP-ID  :  WSRC-TR-2005-00354
RP-ID  :  DE-AC09-96SR18500
RP-ID  :  890195

美国|英语

来源: UNT Digital Library

【 摘 要 】

The Defense Waste Processing Facility (DWPF) began processing Sludge Batch 3 (SB3), Macrobatch 4 (MB4) in March 2004 as part of Sludge Receipt and Adjustment Tank (SRAT) Batch 272. Sludge Batch 3 is a blend of the contents Tank 40 remaining from Sludge Batch 2 (SB2), the sludge that was transferred to Tank 40 from Tank 51 and Canyon Np solution additions made directly to Tank 40. The sludge transferred from Tank 51 contained sludges from Tanks 7, 18 and 19 along with precipitated solutions of U, Pu/Gd and Am/Cm from the F and H Canyons. The blend of sludge from Tank 51, Tank 40, and the Canyon additions defines SB3 (or MB4). The sludge slurry is received into the DWPF Chemical Processing Cell (CPC) and is processed through the SRAT and Slurry Mix Evaporator (SME) Tank and fed to the melter. During the processing of each sludge batch, the DWPF is required to take at least one glass sample. This glass sample is taken to meet the objectives of the Glass Product Control Program and complete the necessary Production Records so that the final glass product may be disposed of at a Federal Repository. Two glass samples were obtained while pouring Canisters S02312 and S02315 which were sent to the Savannah River National Laboratory's (SRNL) Shielded Cells Facility. Sample S02312 was designated for analysis, while sample S02315 was designated for archival storage. This report contains the visual observations of the as-received glass sample, results for the density, chemical composition, the Product Consistency Test (PCT) and the calculated and measured radionuclide results needed for the Production Record for Canister S02312. The following conclusions were drawn from the examination of this DWPF pour stream glass sample: (1) The glass sample taken during the filling of DWPF Canister S02312 weighed 41.69 g and was generally dark and reflective. (2) Minor inclusions, on the order of 1 {micro}m in size, of noble metals were seen in the glass via contained scanning electron microscopy and confirmed from their x-ray fluorescence spectra. (3) The results for the composition of glass sample S02312, except for U, are in reasonable agreement (15% or better) with the DWPF SME Batch 319 results, the SME batch being fed to the melter when the sample was collected. (4) The calculated waste dilution factor (WDF) was 2.19. The measured values of the radionuclides and noble metals in the glass sample generally corresponded well with the calculated values determined using sludge slurry results from Reference 9 and the WDF. (5) The noble metal content of the glass indicates that the noble metals are largely swept from the melter with the glass based upon the noble metals analyzed in the glass and those predicted in the sludge from the WDF. (6) Comparison of the noble metal results for the two digestion methods (mixed acid and alkali fusion) indicates that the alkali fusion method is preferred for the determination of noble metals in glass. (7) The PCT results for the glass (normalized release of B: 1.09 g/L, Na: 1.03 g/L, and Li: 0.94 g/L) indicate that it meets the waste acceptance criterion for durability. (8) The normalized release rates for the measured radionuclides were less than those for the major soluble elements in the waste (B, Na, and Li) with the exception of Tc-99 which was released at a rate similar to that the soluble elements in the leachate. (9) The measured density of the glass was 2.58 {+-} 0.11 g/cm{sup 3}.