Evaluation of improved techniques for the removal of (sup 90)Sr and (sup 137)Cs from process wastewater and groundwater: Chabazite zeolite baseline study

摘要

Standard waste treatment procedures for the removal of (sup 90)Sr and (sup 137)Cs from contaminated groundwater and process wastewaters generate large volumes of secondary contaminated wastes. Several new sorbent materials, ion exchangers, and other processes hold the promise of treating large volumes of contaminated water while minimizing the generation of secondary low-level radioactive wastes. As part of the Efficient Separations/Processes-Integrated Program (ESPIP), these new treatment techniques will be compared with standard processes to define their effectiveness for the removal of radioactive strontium (Sr) and cesium (Cs), as well as to gauge the quantity of secondary radioactive waste generated by the new processes. This report summarizes the efforts made to design standardized testing procedures to evaluate the sorption characteristics of a baseline wastewater treatment technique. Definition of the experimental procedures, as well as a summary of the benchmark sorption technique, will provide the framework with which to compare newly evolving treatment technologies. Accomplishments include selecting the feed strewn to the Process Waste Treatment Plant (PWTP) at Oak Ridge National Laboratory as representative of the prototypical contaminated wastewater of many DOE sites. Samples from the PWTP feed stream were collected and analyzed for metals, anions, total Sr and Cs, radioactive Sr and Cs, alkalinity, pH, and density. The cumulative sample data were used to formulate a simulant that will be used as a standard waste surrogate for comparative testing of selected treatment methods.