Test Results for CSTR Test 3

[摘要] The goal of the Savannah River Salt Waste Processing Program (SPP) is to evaluate and select the most effective technology for the treatment of the high-level waste salt solutions currently being stored in underground storage tanks at the U.S. Department of Energy Savannah River Site (SRS) in Aiken, South Carolina. One of the three technologies currently being developed for this application is the Small-Tank Tetraphenylborate Process (STTP). This process uses sodium tetraphenylborate (NaTPB) to precipitate and remove radioactive cesium from the waste and monosodium titanate (MST) to sorb and remove radioactive strontium and actinides. Oak Ridge National Laboratory is demonstrating this process at the 1:4000 scale using a 20-L capacity continuous-flow stirred-tank reactor (CSTR) system. Since March 1999, three operating campaigns of the 20-L CSTR have been conducted. The ultimate goal is to verify that this process, under certain extremes of operating conditions, can meet the minimum treatment criteria necessary for processing and disposal at the Savannah River Saltstone Facility. The waste acceptance criteria (WAC) for {sup 137}Cs, {sup 90}Sr, and total actinides are <40 nCi/g, <40 nCi/g, and <18 nCi/g, respectively. However, to allow for changes in process conditions, SPP is seeking a level of treatment that is about 50% of the WAC. The bounding separation goals for {sup 137}Cs and {sup 90}Sr are to obtain decontamination factors (DFs) of 40,000 (99.998% removal) and 26 (96.15% removal), respectively. The DF is defined as the concentration of contaminant in the waste divided by the concentration of contaminant in the effluent stream.

[发布日期] 2000-10-12 [发布机构] Oak Ridge National Laboratory

[关键词] Removal;Capacity;Sodium;Actinides;Processing