Mediating Operation of Catalytic CSTR to Stabilize Intermediate Steady State

A novel approach for stabilizing the intermediate steady state of a continuous stirred-tank reactor (CSTR) is proposed by using a special type of periodic forced operation, the so-called mediating operation. The mediating operation enables new additional steady states for which one of the new intermediate steady states is stable to be produced. Thus the proposed approach employs a periodic forcing for stabilization of a selected steady state by control of a steady-state multiplicity. The feed flow rate is considered to be a manipulated variable. Changing CSTR multiplicity is investigated for two-step control inputs. It is shown, analytically, that under two-step control CSTR can exhibit at most five steady states with a stable intermediate steady state. A constructive procedure is proposed for finding control parameters corresponding to maximal multiplicity, that is, for stabilizing an intermediate steady state by two-step control.