Studies in the synthesis of control structures for chemical processes. Part V: Design of steady‐state optimizing control structures for integrated chemical plants

This paper addresses the question of how to design the steady‐state optimizing control system for a large scale interconnected chemical plant. The integrated design approach is structured within the framework of the hierarchical control theory and is based on the concepts of constraint control, hierarchical decomposition and nonlinear mathematical programming. Theoretical developments lead to the generation of alternative operational policies of practical value. An imbedded branch and bound screening strategy is given to select the best policy, which will be implemented on‐line by the optimizing plant controllers. The general design approach has the broad applicability to any interconnected large scale system, and its application is demonstrated on a gasoline polymerization plant.