TANK 40 FINAL SB4 CHEMICAL CHARACTERIZATION RESULTS

Best, J

关键词: AR FACILITIES;    SLUDGES;    RADIOACTIVE WASTES;    CHEMICAL COMPOSITION;    MULTI-ELEMENT ANALYSIS;    SAVANNAH RIVER PLANT;    STORAGE FACILITIES;    SAMPLING;    SAMPLE PREPARATION;   

DOI  :  10.2172/923830
RP-ID  :  WSRC-STI-2007-00674
PID  :  OSTI ID: 923830
Others  :  TRN: US0802189

学科分类：核能源与工程

美国|英语

来源: SciTech Connect

【 摘 要 】

A sample of Sludge Batch 4 (SB4) was pulled from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS). This sample was also analyzed for elemental and chemical composition including noble metals. These analyses along with the WAPS analyses will help define the composition of the sludge currently in Tank 40 which is currently being fed to DWPF and will become part of Sludge Batch 5 (SB5). At SRNL the 3-L Tank 40 SB4 sample was transferred from the shipping container into a 4-L vessel and solids allowed to settle overnight. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 280 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples. Eight separate aliquots of the slurry were digested, four with HNO{sub 3}/HCl in sealed Teflon{reg_sign} vessels and four in Na{sub 2}O{sub 2} using Zr crucibles. Due to the use of Zr crucibles and Na in the peroxide fusions, Na and Zr cannot be determined from this preparation. Three glass standards were digested along with a blank for each preparation. Each aqua regia digestion and blank was diluted and submitted to Analytical Development (AD) for inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis, inductively coupled plasma-mass spectrometry (ICP-MS) analysis, and cold vapor atomic absorption (CV-AA) analysis. Equivalent dilutions of the peroxide fusion digestions and blank were submitted to AD for ICP-AES analysis. Tank 40 SB4 supernate was collected from a mixed slurry sample in the SRNL Shielded Cells and submitted to AD for ICP-AES and ICP-MS. Weighted dilutions of slurry were submitted for ion chromatography (IC), total inorganic carbon/total organic carbon (TIC/TOC), and total base analyses. A sample of Tank 40 SB4 decant was collected by carefully removing the supernate phase from a settled sample. This decant was not filtered prior to performing a warm nitric acid digestion of the material in order to measure the Si content by ICP-AES. Three Si standards, a blank, and a matrix standard were prepared and submitted along with the Tank 40 samples. The following conclusions were drawn from the analytical results reported here: (1) The elemental composition of this sample and the analyses conducted here are reasonable and consistent with DWPF batch data measurements; (2) There was no measurable Si in samples of Tank 40 decant; and (3) Ag and the Ru, Rh, and Pd noble metal concentrations agree well with the estimate used for the SB4 70/30 blend of SB3 and Tank 51 performed in the SRNL Shielded Cells.