Evaluating Defoaming Agents for the Stripping Columns at the In-Tank Precipitation Facility

摘要

The In-Tank Precipitation (ITP) process will concentrate the Tank 48 contents to approximately 10 wt. percent tetraphenylborate solids by filtration. The filtrate produced during the process flows to the ITP stripping columns where the soluble benzene is removed from the solution. It has been observed that a large pressure differential occurs across the column packing when the filtrate is processed in the column. One potential explanation for the pressure differential is that the filtrate is foaming in the column. Small scale stripping tests have verified that the salt solution foams. Waste Management requested assistance from SRTC in solving the foaming problem through technical task requests HLE-TTR-93013A/B (Benzene Stripper Performance Evaluation) and HLE-TTR-93044 (Kinetics of Benzene and Dissolution). Various tests were completed to determine an effective defoaming agent for use in the stripping columns. This document discusses the tests and the conclusions.