Multilevel Predictive Control System for an Activated Sludge Wastewater Treatment Process

This paper deals with multilevel (hierarchical) control and optimization of a conventional Wastewater Treatment Plant (WWTP). A multilevel system to control the plant operation that satisfies the effluent water quality requirements and increases the plant energy efficiency is described. The first level contains the basic process control loops and the second level, the optimization level, provides optimal setpoint values for the first level control loops based on the Extended Prediction Self-Adaptive Control (EPSAC) method. The proposed control strategy was investigated and evaluated by performing simulations and analyzing the results. Both the set point tracking and the regulatory performances have been tested.