Aqueous Phase Composition and Entrainer Pricing

The annual cost of this stream is not only related to its flowrate but also related to the entrainer pricing. Ethyl acetate is the cheapest and isobutyl acetate is the most expensive entrainer. With the knowledge of the entrainer pricing and the calculation of the makeup flowrates for the three systems, the entrainer cost can be estimated as seen in Table 9.13, even without any rigorous simulation. 

One important thing that needs to be pointed out from the table is that in order to hold product specifications, the aqueous reflux flowrate needs to be adjusted in a very wide 

TABLE 9.14 Desired Operating Condition Under Various Feed Compositions. 

Feed Water Composition (mol%) Aqueous Reflux (mol/min) Organic Reflux (mol/min) Reboiler Duty (KW) Entrainer Makeup (mol/min) Aqueous Draw (mol/min) Bottom Product (mol/min) 

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