(224e) Multi-Scale Comparison of Supernatant Tank Waste Hydraulic Performance

Execution of the Hanford Site’s Direct Feed Low-Activity Waste process requires a pretreatment step prior to vitrification in the Low-Activity Waste (LAW) Facility at the Hanford Waste Treatment and Immobilization Plant (WTP). Tank waste supernatant pretreatment is being performed by the Tank Side Cesium Removal (TSCR) system, which was designed to conduct two separations to prepare LAW for vitrification. The separation steps are (1) dead-end filtration using a Mott Grade 5 sintered stainless-steel filter and (2) ion exchange in packed columns to remove Cs-137 using crystalline silicotitanate. The TSCR separation technologies have been tested extensively at multiple scales with both actual and simulated waste; recently, the TSCR system has also begun treatment operations.

During normal operations in various test systems and the TSCR system itself, the processing flow rate is constant. The dead-end filters and ion exchange columns respond with changes in hydraulic performance, i.e., differential pressure, as solids accumulate in the system or the fluid’s physical properties change. The availability of test data collected at multiple scales, including the “full-scale” TSCR, permits examinations of performance to be made based on selected dimensionless parameters. Test data sets will be presented, followed by a comparative examination to assess the viability of making full-scale performance projections from less-than-full-scale test systems, as well as the efficacy of using simulant test data in place of data collected using actual tank waste.