Application of constraint-based fuzzy logic controller for pH control of a flue gas desulfurization system

In this paper, we present the design of a constraint-based fuzzy logic controller (CFLC) for pH control of a flue gas desulfurization (FGD) system. Based on the concept of a CFLC, the control strategies for the FGD process are modeled as a network; the control actions are then governed to the intended states of satisfying all the constraints in the network. Additionally, we also include the simulation results to show the effectiveness of CFLC for the FGD system, while it has not been successfully dealt with through either the conventional PID or rule-based fuzzy logic approach.