Ethanol can be made by fermentation of grains such as corn. It can be fermented only up to a mass fraction of about 0.15 because higher concentrations kill the yeast. A big market for ethanol made this way is as an additive to gasoline. Suppose that you have 90 kg/h of gasoline, the lean stream, and you would like to increase its concentration of ethanol from zero mass fraction to 0.09. You have two rich ethanol-water streams from fermentation processes. One is at 60 kg/h and a mass fraction of 0.09, and the other is at 30 kg/h and a mass fraction of 0.12. It is desired to reduce the ethanol mass fraction in the rich streams to a mass fraction of 0.02. The partition coefficient between the rich and lean streams is 1.2 (i.e., y = 1.2x), where y is the mass fraction in the ethanol-water (rich) stream and x is the mass fraction of ethanol in the gasoline (lean) stream.

Synthesize the MUMNE mass-exchange network for a minimum approach composition of d = 0.01.