Analysis of Characteristics of Cryogenic Distillation Column in Separation of Hydrogen Isotopes

Mass and heat transfer mechanisms of cryogenic distillation columns were studied to determine the dependence of the HETP on parameters such as phase flow rates and flow condition within the columns. The mass and heat transfer rates were calculated on the basis of the laminar boundary layer theory (diffusion model) and the Chilton-Colburn analogy (analogy model). The results calculated by these models were compared with experimental observations and those by the stage model. The stage model gave the best fit with the experimental observations. However, some data were in agreement with the results by the diffusion and analogy models. For these data, the HETP differed from component to component. From the simulation results by the analogy model it was observed that the overall mass transfer rate was proportional to the vapor velocity within the column. The HETP was unchanged against the vapor velocity because of this relationship between mass transfer rate and vapor velocity.