Journal of Chemical Engineering of Japan, Vol.34, No.3, 312-318, 2001
Optimization aspects for reactive batch distillation
The optimal operation problem of a reactive batch distillation column is solved for various types of models and also for different objective functions, As the base case a detailed model, including a dynamic energy balance, is developed for the process producing ethyl acetate, The reflux ratio and the heat duty are selected as the variables to be optimized and are assumed to be piecewise constant. First, the effect of the number of piecewise constant time periods on the value of the objective function is investigated. The result indicates that the performance is considerably improved with an increase in the number of time periods. The optimization results, evaluating the effect of the reaction on the trays, show that, compared with the case where the reaction occurs only in the reboiler, the reaction on the trays sometimes has a negative impact on the progress of the reaction, The results obtained from the models of different preciseness show that the assumptions of an algebraic energy balance sometimes overestimate the performance of the column. The effects of the holdup dynamics, the type of objective function, and the non-ideality of the VLE model are also discussed by comparing various optimization results.
Keywords:process systems engineering;reactive batch distillation;dynamic optimization;ethyl acetate;distillation modeling