Simulteaneous Design and Control of a Pollymerization Process. I

ASTEASUAIN, MARIANO; SARMORIA, CLAUDIA; BRANDOLIN, ADRIANA; BANDONI, ALBERTO

Viña del Mar

Simposio; II Simposio Argentino-Chileno de Polímeros; 2003

Universidad de Chile

Traditionally, operational aspects of chemical processes (optimum operation and control) have been treated sequentially with the system design. That is, first the process is designed to achieve an optimum objective using a fully specified nominal case. Only then operability aspects (i.e. control system design, security, flexibility) are taken into account. This approach, however, does not consider that process security, flexibility and dynamic controllability are an inherent property of its design, which also affects process economics. The importance of integrating system design and operability has been recognized, and motivated an increasing interest by both academia and industry in the field. In polymer science, however, very little work has been done in this direction so far.In the present study we focus on the simultaneous design and control of a semi-batch styrene polymerization reactor. A single optimization problem is solved in which both process design variables and control system are optimally determined. At the same time, feasible operation is achieved, where feasibility is defined in terms of product specifications and process constraints. The presence of discrete decision variables gives rise to a Mixed Integer Dynamic Optimization (MIDO) problem, which is solved with the gPROMS/gOPT v2.2.6 package (Process Systems Enterprise Ltd.).