화학공학소재연구정보센터
Industrial & Engineering Chemistry Research, Vol.53, No.3, 1189-1205, 2014
Design and Control of Extractive Dividing-Wall Column for Separating Ethyl Acetate-Isopropyl Alcohol Mixture
An extractive dividing-wall column (EDWC) is simulated as a three-column system in this work. The design and control of the EDWC to separate ethyl acetate and isopropyl alcohol using ethylene glycol as the entrainer is studied in Aspen Plus and Aspen Dynamics. The optimum EDWC design with minimal total annual cost is screened first; then sensitivity analysis is conducted to investigate whether the entrainer flow rate and vapor split ratio can be used as control variables to hold the purity specifications; finally, three control structures for the EDWC are established, and the dynamic results of these control structures are compared. It is found that two improved control structures achieve satisfactory performance with much smaller deviation and shorter settling time by comparison to the basic control structure. Dynamic results also revealed that it is useful to adjust the entrainer flow rate or vapor split ratio to hold the purity specifications.