On-Line Optimizing Control of a Fixed Bed Reactor

A scheme of on-line steady-state optimizing control is presented for a fixed bed reactor which experiences a highly exothermic reaction. The control scheme has been devised to perform two functions simultaneously, adaptive control of a bed temperature and on-line steady-state optimization by recursively identifying the reactor dynamics. Experiments were done with a pilot-scale fixed bed reactor where a partial oxidation of n-butane to maleic anhydride occurs. The reactor system was interfaced with a microcomputer for real-time control and optimization. With an objective function which consists of a net profit by producing maleic anhydride plus a penalty term on the bed temperature, it was clearly shown that the reaction conditions were driven to a supposedly optimum point.