Integrated design and control of semicontinuous distillation systems utilizing mixed integer dynamic optimization

• First study on the integrated design and control of semicontinuous distillation system.
• Presents a methodology for synthesis of semicontinuous distillation system for any arbitrary ternary mixture.
• Mixed integer dynamic optimization of the semicontinuous system to determine structural and operational variables.
• Comparison of the deterministic outer approximation optimization method with the heuristic particle swarm optimization.
• Economic analysis of the final structure.

Semicontinuous distillation systems are notoriously difficult to design and optimize because the structural parameters, operational parameters, and control system must all be determined simultaneously. In the past 15 years of research into semicontinuous systems, studies of the optimal design of these systems have all been limited in scope to small subsets of the parameters, which yields suboptimal and often unsatisfactory results. In this work, for the first time, the problem of integrated design and control of semicontinuous distillation processes is studied by using a mixed integer dynamic optimization (MIDO) problem formulation to optimize both the structural and control tuning parameters of the system. The public model library (PML) of gPROMS is used to simulate the process and the built-in optimization package of gPROMS is used to solve the MIDO via the deterministic outer approximation method. The optimization results are then compared to the heuristic particle swarm optimization (PSO) method.