A general mathematical model based on the principal of non-equilibrium thermodynamics is proposed for analyzing the energy consumption of trayed column distillation processes related the tray structures. It can be used not only to calculate the energy consuming in different operational conditions, but also,and more importantly, to evaluate the entropy generation rate (EGR) of the different tray structures and different liquid flow patterns on the tray of the column. Therefore, this model has been used for the technical instructions in the design of a new energy-saving tray.

An energy-saving tray with novel structures--diamond-shaped dobble-deck valve tray (simply called DDV tray,shown in figure 1 and 2) was designed based on the results through the analysis of entropy generation rate (EGR) of non-equilibrium thermodynamics. The experiments of pressure drop, temperature variations in liquid phase and tray efficiency of the tray were carried out on a pilot column with a diameter of 1000mm. The results showed that DDV tray have the remarkable advantages in capacity, efficiency and energy-saving, over F1 tray, traditional sieve tray and rectangle-shaped valve tray, etc.