A depropanizer distillation column (DDC) that is widely used in oil refineries, was simulated by Aspen Plus using both equilibrium and non-equilibrium models. The purpose of this simulation was selecting the most appropriate model to accurately predict the separation process in the DDC. Considering the temperature profile and mole fraction diagrams of the desired product (propane) in the distillation column, it was found that the equilibrium and non-equilibrium models differ significantly in predicting the column behavior. Comparing the industrial data of the DDC with the results of the two mentioned approaches, it can be concluded that the non-equilibrium model with the mass transfer coefficient from Chen and Chuang (1993) can simulate the DDC accurately.
