Krypton absorption in liquid CO2 (KALC): effects of the minor components N2, CO, and Xe

Results are presented for the fourth major campaign for quantifying krypton removal from simulated High-Temperature Gas-Cooled Reactor reprocessing off-gas by the Krypton Absorption in Liquid CO2 (KALC) process. This process utilizes the high solubility of krypton in liquid CO2. Mass transfer experiments for the absorption, fractionation, and stripping operations of the KALC process indicate that the addition of N2 and CO do not alter the mass transfer characteristics exhibited by O2 and krypton in the basic CO2--O2--Kr system. Decontamination factors for xenon in the absorber and stripper were several orders of magnitude less than those for krypton under similar conditions. Indications are that the fate of xenon is controlled by the heat input to the stripper reboiler. Experiments on the solubility of O2 and CO indicate that CO is more soluble than O2 at temperatures below -210C