Optimal design and operation of a multi-product batch distillation column using dynamic model

Abstract

Although the operation of a batch distillation column involves dynamic behavior from the beginning to the end, the quasi-steady state model or the short-cut method has been widely implemented in the design of the column owing to simple computation in spite of the expected discrepancy with real process operation. In this study, a dynamic process model is utilized in the optimal design of the batch distillation process and the successive quadratic programming is employed as an optimization procedure. A ternary system is examined to see that the dynamic model design gives a significant improvement, especially for the operation having a dynamic manipulation of reflux ratio. The outcome of the optimization for the example system indicates that more amount of product with less operation time than that of the quasi-steady model is available. In addition, the optimization of net profit tells that the optimum number of trays is 23 for the sample system. The optimum operation schedule of the system is also obtained from the optimization of operational profit. Finally, the effect of side product recycle is investigated.