Separating Mixture Glycols in DWC with Flow Rate-Composition Cascade Control Structure

Dividing wall column (DWC) is an advanced technology which could decrease energy consumption. As the vertical inserted in DWC increases degree of freedom systems, control becomes more difficult than conventional columns. In this study, mixture glycols (1, 2-propanediol+ 1, 3-butanediol+ 4-butanediol) were taken as feed, optimized structure was proposed, and three structures for tested by ± 10% feed disturbances. The temperature (CS1) hard to system while composition (CS2) flow rate-composition cascade (CS3) had good performance on controlling DWC. It showed that CS3 superior CS2, stabilize within 4 hours, maximum deviations products, namely 2-propanediol, 3-butanediol 4-butanediol, 0.07%, 1.44%, 0.46% respectively, CS2 realize stability 7 corresponding numbers 0.35%, 2.78%, 0.41%, respectively.