Test Results for CSTR Test 4

One of the 3 technologies currently being developed for the Savannah River Salt Waste Processing Program is the Small-Tank Tetraphenylborate Process (STTP). This process uses sodium tetraphenylborate to precipitate and remove radioactive Cs from the waste and monosodium titanate to sorb and remove radioactive Sr and actinides. ORNL is demonstrating this process at the 1:4000 scale using a 20-liter continuous-flow stirred tank reactor (CSTR) system. The primary goal of Test 4 was to verify that the STTP process could achieve and maintain the necessary Cs decontamination while TPB was actively decomposing. Even with TPB being decomposed by the off-normal conditions of this test, the decontaimination factor for {sup 137}Cs obtained for the filtrate from the Slurry Concentrating Tank ranged from 47,000 to 646,000, exceeding the WAC standard