Measurement of Plant Flexibility

摘要

Operational flexibility is an important consideration when designing and operating a chemical plant.Very often,flexibility is concerned with insuring feasible steady-state operation over a variety of operating uncertainties.To quantify how flexible a process is,various metrics have been developed.However,these metrics are either too difficult to compute or unable to provide comprehensive evaluation.This paper aims at introducing a new process flexibility metric.Flexibility is reckoned as the feasible space's (S_f 's) size in which the uncertain parameters can be feasibly handled.A new flexibility index (FI_Y) is defined as the size ratio of S_f to the overall space (SJ bounded by the uncertain parameters' expected limits.The FI_V measures the entire space where all uncertain parameters can be freely moved.An algorithm used for evaluating FI_V is provided.Examples are presented to demonstrate the applications of FI_v and compare this with other flexibility measurements.