I get a different minimum reflux ratio

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I am using the latest version of DWSIM, namely, 6.4.6. I have followed every step exactly, I think. I get the minimum reflux Rmin to be 1.0352 (and not 1.65, as mentioned in the tutorial). As the reflux used is 1.5, which is higher than Rmin, I get the minimum number of stages to be 7.6 and the actual number of stages to be 15.013.

Are the above values expected, or am I making any mistake?

DWSIM Shortcut-Distillation 07-08 min 30-40 sec

__Answers:__

In the tutorial, it is mentioned that Flash Spec for the Feed stream should be Pressure and Vapor Fraction (PVF) where pressure is entered as 1 atm and Vapor Fraction is entered as 0. If you do that, you will definitely get the minimum reflux ratio to be 1.65 as mentioned in the tutorial.

I think you are using the Flash Spec for the Feed Stream as Temperature and Pressure (TP) where the temperature is 25 degrees C and pressure is 1 atm which is different than what is demonstrated in the tutorial video. If you are using these values, you will get the minimum reflux Rmin to be 1.035. However, if you wish to use these modified feed stream conditions, then the min number of stages and the actual number of stages that you get are expected.

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