Multivariable computer control of a butane hydrogenolysis reactor: Part III. On‐line linear quadratic stochastic control studies

Abstract A linear low‐order state space dynamic model for a catalytic butane hydrogenolysis reactor which has been fitted to reactor dynamic data is used to develop a multivariable linear quadratic feedback control algorithm for regulatory control of the reactor exit concentrations using temperature measurements only. Kalman filter theory is used to obtain state estimates for the system. The control algorithm developed is implemented on the pilot plant reactor in a series of DDC control studies. The controller is shown to perform very well and considerably better than a single loop PI controller with a feedback on the hot spot temperature. Performance is evaluated both under the normal stochastic disturbances in the system and under a severe deterministic load disturbance. Exit concentrations predicted by the model and used in the performance index are shown to compare very favorably with actual concentrations obtained from a process gas chromatograph.