Optimal retrofit design for improving process flexibility in linear systems

Abstract: "In this paper the problem of optimally redesigning an existing process to increase its flexibility is addressed. A general strategy which first determines the optimal parametric changes and then identifies the optimal structural modifications is presented. For linear models basic analytical properties of flexibility are presented with which very efficient reduced LP and MILP formulations can be developed for parametric and structural modifications. Also, trade-off curves relating flexibility to retrofit cost can easily be generated to provide information on the cost of flexibility. Examples are presented to illustrate the proposed procedures."