SHORT-CUT METHOD FOR PROCESS CONTROL AND OPERABILITY ANALYSIS.

A method for process control and operability analysis which requires limited engineering effort is presented in this paper. The method is used to design control schemes for multivariable systems based on predicted control performance; design decisions involve selecting control schemes and loop pairing and determining when decoupling is appropriate. The method involves three approaches of increasing complexity. The first approach uses only steady-state gains to estimate the effects of interaction on control performance. The second uses further design data to develop approximate dynamic models and better estimates of control performance. The third uses a simplified, block-oriented simulation to give more information on the transient response. The overall method is useful for industrial problem solving; several examples of distillation control are presented.