CONTROL OF CONTINUOUS REACTORS WITH NON-MONOTONIC REACTION RATE

Abstract

In this paper, the problem of controlling a (possibly open-loop unstable) continuous exothermic chemical reactor with non-monotonic reaction rate, maximum production rate specification, and temperature measurements is addressed. The problem difficulty resides in the lack of reactor local observability at the nominal steady-state. A nonlocal constructive design approach leads to a passivated control scheme with linearity, decentralization and reduced model dependency features as well as nonlocal closed-loop behavior. The resulting control scheme resembles industrial type components: a linear PI cascade temperature controller, and a ratio inventory-based feedforward concentration controller. The approach is tested with a typical case example through numerical simulations.