SAFEGUARDS BY DESIGN: MULTIMODAL IN-PROCESS MONITORING OF MOLTEN SALT COMPOSITION

摘要

Tracking the composition of molten salt as it moves through an electrochemical fuel reprocessing facility is challenging because the material processing is done continuously at elevated temperatures, while transfers involve discrete batches of used fuel or solids with adhered salts. Salt is recycled at several points within the process, making it difficult to relate changes in composition to specific processing operations. Particularly over long time steps, small differences or inhomogeneities may result in quantifiable changes in product output compositions. Molten salt reactors possess similar challenges with respect to safeguarding of actinides within fuel salts. To enable process monitoring, material tracking, and pattern recognition for safeguards in these complex systems, multimodal in-process measurements of salt composition will be required. The Materials Protection, Accounting, and Control Technologies (MPACT) program within DOE NE is working toward a 2020 milestone to demonstrate advanced Safeguards and Security by Design for a generic electrochemical reprocessing facility. This paper will discuss a suite of tools being developed under the MPACT program to fill identified gaps in the safeguards approach for such a facility. The new tools will support in-situ salt characterization as well as automated on-line, at-line, and off-line sampling-based salt characterization. One of the new platforms is a sampling loop with sample extraction and on-line optical analysis capabilities. This platform was designed to support high-throughput sampling-based measurements, which will not only improve the timeliness of sampling-based analysis but will also reduce statistical uncertainties of measurements. These sampling technologies, when combined with advanced electroanalytical sensors, will provide crucial information for the safeguards and process monitoring of a variety of fuel reprocessing equipment. Development and testing efforts for these capabilities will be discussed along with process integration and deployment opportunities.