Automatic Design and Optimization of Column Sequences and Column Stacking Using a Process Simulation Automation Server

Simulation–optimization is applied to determine nearly optimal process designs in column sequencing and stacking problems using a simulated annealing algorithm (SAA) in the client (MATLAB) and a single distillation column in the server (Aspen Plus). Each column in every sequence is optimized separately, and the total cost of each sequence is calculated. This method benefits from both the rigor of column modeling in a process simulator and the flexibility of implementing sequential procedures and derivative-free optimization in a procedural programming language. Using this method, a single column can be optimized within 6 min of computer time. Furthermore, when stacking rules and available utilities are specified, a nearly optimal heat-integrated distillation column sequence can be designed automatically. Results are illustrated using two case studies of column sequencing problems.