Mass transfer in ternary distillation of nitrogen-argon-oxygen system in wetted-wall column

Experiments on ternary distillation were made for a nitrogen-argon-oxygen s ystem in a wetted-wall column under total reflux conditions for wide ranges of vapor concentrations and flow rates (especially turbulent flow region), and simultaneous heat and mass transfer was examined. Heights of transfer units for the intermediate component, argon, show disco ntinuity near the zero driving force region. The observed diffusion fluxes of each component in ternary distillation are found to be proportional to t heir concentration driving forces, whereas the observed mass fluxes are not . This is due to the convective mass fluxes caused by mass fluxes of the ot her components. The observed diffusion fluxes in the ternary distillation o f air show good agreement with the previously developed binary correlation using Wilke's effective diffusion coefficients. The separation performance of cryogenic air distillation under total reflux conditions in a wetted-wall column is predicted by using the correlation f or ternary diffusion fluxes, Predicted separation performance shows good ag reement with the observed data. The effect of interaction between diffusion fluxes in air distillation is also discussed.