A safeguards approach for uranium and plutonium bearing molten salts requires knowledge of their concentrations as well as the total salt volume in order to determine the total mass of each in the process vessel. Means to achieve these measures has been a focus of the Department of Energy (DOE) Materials Protection, Accounting and Control Technology (MPACT) campaign. As part of this effort, a triple bubbler sensor has been developed at the Idaho National Laboratory (INL) to measure the salt depth and density (obtain salt volume) in a vessel containing molten salts. From laboratory results, the developed sensor has shown to provide density and depth measurements that are well below the needed 1% uncertainty threshold desired for material accountancy purposes. However, in extended field tests, a weakness in the current design was identified, dip-tube plugging occurred after several weeks of continuous operation. Focused experiments have been conducted to identify the dip-tube plugging mechanisms and to explore mitigation and maintenance options. Results from the testing will provide insights into the operation and future designs of a triple bubbler sensor.
Year
2020
Abstract