CONTROL STRUCTURE DESIGN FOR A REACTOR/SEPARATOR PROCESS WITH TWO RECYCLES

A hierarchical controller is designed for a reactor/separator system which consists of a CSTR and two distillation columns with two material recycles. In designing the lower level regulatory control layer, the overall system is divided into subunits, for which regulatory control for inventories and product compositions is designed relatively independently. The higher level coordination controller is designed so that the steady state performance is near-optimal. The coordination controller manipulates some of the interconnecting flows between the subunits, namely the two recycle flows, looking at the separator loads. Control performance is demonstrated through simulations.