PNNL

Abstract

The U.S. has a vested interest in advancement of nuclear energy to achieve aggressive net-zero goals, with reprocessing and recycling playing a vital role. It will not be possible to meet U.S. regulatory requirements without robust off-gas treatment. It is crucial to advance treatment technologies to facilitate design of future reprocessing facilities. To that end, teams of researchers across the U.S. Department of Energy (DOE) National Laboratory complex have been investigating off-gas treatment technologies for the capture and removal of volatile radionuclides (i.e., 85Kr, Xe, 14C and 129I) and oxides of nitrogen (NOX) produced from the reprocessing of used nuclear fuels (UNF) for many years. These investigations have been focused on individual technologies for the capture of Kr, Xe, iodine, and CO2 separately from each other using non-radioactive surrogates. The tests have been relatively small laboratory-scale experiments of up to approximately one liter per minute total gas flow rates. To increase the readiness of these technologies to deployment, an integrated test system at a larger scale capacity is needed to bridge the gap between promising bench scale and fully scalable UNF reprocessing off-gas treatment. This document contains the goals, design basis, functional requirements, preconceptual design and cost estimates for an integrated off-gas demonstration system for the capture and removal of NOx, Kr, Xe, CO2 and iodine at 10× higher throughput than earlier laboratory studies. The order-of-magnitude cost estimate for this system is approximately $800,000. Next phases include conceptual design, detailed design, fabrication, and commissioning.