Melt Rate Assessment of SB/2/3 with Frit 418 - Effects of Waste Loading and Acid Addition

Preparations are being made by the Defense Waste Processing Facility (DWPF) to blend Sludge Batch 2 (SB2) with Sludge Batch 3 (SB3) (blend referred to as SB2/3), and implement a frit change from Frit 320 to Frit 418. A series of dry-fed tests have been performed to investigate the effect of waste loading (WL) on the melt rate of the SB2/3-Frit 418 system. As was observed in the SB2-Frit 320 system, dry-fed melt rate furnace (MRF) tests of the SB2/3-Frit 418 system showed that melt rate decreased as the waste loading increased (WL range of 31-43 per cent tested). In addition, waste throughput of the SB2/3-Frit 418 system reached a peak (at approximately 34 per cent WL) with increased waste loading before steadily decreasing (based on MRF tests). Based on this testing, the Immobilization Technology Section (ITS) recommends that the waste loading starting point for DWPF should be approximately 34 per cent when the processing of the SB2/3 begins with Frit 418. The current target waste loading for DWPF is 34 per cent with SB2-Frit 320, and the results from this testing do not indicate any reasons to reduce this target. Then after a period of steady processing,incrementally higher waste loadings may be evaluated in order to determine the actual waste throughput peak for radioactive vitrification of SB2/3-Frit 418 feed at DWPF