Given the boiling point-liquid phase composition of a mutually soluble ternary system, how to use the Aspen property regression tool to derive vapor-liquid equilibrium data
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As the title suggests, given the boiling point-liquid phase composition of a mutually soluble ternary system, how can vapor-liquid equilibrium data be obtained using Aspen’s property regression tool? (Note: The liquid phases are completely miscible; it is not the type with two separate liquid phases.)
Select TXY for DATATYPE, and enter the pressure of your data below. On the second tab, fill in the temperature composition data; I’m not sure if you have the y-component available, so it’s not clear whether regression is possible. After that, select the regression mode, create a new regression analysis, select the data from earlier, and choose the equation to be used for regression – UNIFAC is usually the choice. On the second page, under Parameters, select the parameters that are to be regressed. Run it; that’s the procedure
Thank you for your reply. The issue is that I don’t have data on the vapor phase composition; I only have the boiling point and the liquid phase composition, so I’m not sure which type of data to use. I’ll try using TXY for now. Some literature indicates that the boiling point-liquid phase composition data can be converted into gas-liquid equilibrium data through conversion; I wonder if Aspen has this functionality?
I’m not sure about this, but if it’s at low pressure, you can estimate a value; it will basically satisfy Raoult’s law, which is better than nothing
You can give it a try; this method is also good
This post was last edited by *amingteda on 2019-7-26 09:04. Theoretically, for ternary systems it is necessary to revert to vapor-liquid equilibrium parameters; however, with only three sets of vapor-liquid equilibrium data, the amount of information available seems insufficient. It is recommended to obtain vapor-liquid equilibrium data at 22°C, and then regress the binary interaction parameters of the thermodynamic model corresponding to each data set, in order to achieve greater accuracy. From the problem statement, it seems you don’t have vapor-liquid equilibrium data; only T-x values are available. It is likely sufficient to proceed with predictions alone