Separation of helium and hydrogen isotopes by ISS at the TSTA

Several experiments were performed with the Isotope Separation System (ISS) at the Tritium Systems Test Assembly (TSTA) from 1988 through 1989. These experiments included two-column experiments with D-T mixtures and four-column experiments with D-T mixtures and impurities (He and H₂). The objectives of these experiments were (1) to obtain fundamental data on cryogenic distillation columns under a wider range of operational condition than in previous work, (2) to observe the influence of He on the operation on cryogenic distillation columns, and (3) to obtain fundamental data on cryogenic distillation columns under the influenced of He. Previous ISS experiments have been performed to obtain fundamental data by using a single column or two columns of the ISS at the TSTA with D-T mixtures. In previous experiments, the HETP (height equivalent to a theoretical plate) value and the pressure drop in the packed section were measured in the vapor velocity range of 5-15 cm/s and in the reflux ratio of 5-40. The result showed that the HETP value was not influenced by the vapor velocity and there was no evidence of a flooding point or loading point. This year, the experiments were performed in the vapor velocity range of 2-15 cm/s and reflux ratio range of less than 230. Continuous separation of He from D-T mixtures was tested for the purpose of obtaining data on ISS operation under the influence of He