Preliminary Scaling Estimate for Select Small Scale Mixing Demonstration Tests.

摘要

The Hanford Site double-shell tank (DST) system provides the staging location for waste that will be transferred to the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Specific WTP acceptance criteria for waste feed delivery describe the physical and chemical characteristics of the waste that must be met before the waste is transferred from the DSTs to the WTP. One of the more challenging requirements relates to the sampling and characterization of the undissolved solids (UDS) in a waste feed DST because the waste contains solid particles that settle and their concentration and relative proportion can change during the transfer of the waste in individual batches. A key uncertainty in the waste feed delivery system is the potential variation in UDS transferred in individual batches in comparison to an initial sample used for evaluating the acceptance criteria. To address this uncertainty, a number of smallscale mixing tests have been conducted as part of Washington River Protection Solutions Small Scale Mixing Demonstration (SSMD) project to determine the performance of the DST mixing and sampling systems. The purpose of the 2013 testing was to estimate scaling relationships for waste feed delivery tank performance metrics, in particular transfer UDS concentration. A statistically designed test plan was used to generate accurate and quantifiable correlations. These tests also used a simulant that better represented Hanford Site tank waste. The solids mixtures used in the base simulant for these tests is similar to the 2011 multicomponent Complex 5 simulant, however, the 2013 Base simulant has two variations, a typical and more challenging, high base loading. The liquid fraction of the simulant is tailored to provide corresponding typical and high viscosities, which better represent the Hanford Site tank waste supernatant. Water was used as the liquid fraction of the simulant in 2011 SSMD testing.