Evaluation of Glass Density to Support the Estimation of Fissile Mass Loadings from Iron Concentrations in SB8 Glasses.

摘要

The Department of Energy-Savannah River (DOE-SR) has provided direction to Savannah River Remediation (SRR) to maintain fissile concentration in glass below 897 g/m3. In support of that guidance, the Savannah River National Laboratory (SRNL) provided a technical basis and a supporting Microsoft Excel spreadsheet for the evaluation of fissile loading in Sludge Batch 5 (SB5), Sludge Batch 6 (SB6), Sludge Batch 7a (SB7a), and Sludge Batch 7b (SB7b) glass based on the iron (Fe) concentration in glass as determined by the measurements from the Slurry Mix Evaporator (SME) acceptability analysis. SRR has since requested that the necessary density information be provided to allow SRR to update the Excelm spreadsheet so that it may be used to maintain fissile concentration in glass below 897 g/m3 during the processing of Sludge Batch 8 (SB8). One of the primary inputs into the fissile loading spreadsheet includes an upper bound for the density of SB8-based glasses. Based on the measured density data of select SB8 variability study glasses, it is recommended that SRR utilize the 99%-/99% Upper Tolerance Limit (UTL) density values given below as upper bounds for the densities of the SB8 glass system at the waste loadings (WLs) as indicated. Thus, these bounding density values are to be used to assess the fissile concentration in this glass system. It should be noted that no changes are needed to the underlying structure of the Excelm-based spreadsheet to support fissile assessments for SB8. However, SRR should update the other key inputs to the spreadsheet that are based on fissile and Fe concentrations reported from the SB8 Waste Acceptance Product Specification (WAPS) sample.