Set-point optimization for enhancing the MPC control of the N-removal process in WWTP´s

In this paper, an steady state set point optimization is applied to improve the Model Predictive Control (MPC) performance in the nitrogen removal reactors of a Wastewater Treatment Process (WWTP). The objective is to find out the set points that optimizes the Effluent Quality (EQ) and the energy costs for a dry season characteristic influent. An MPC algorithm that guarantees offset-free control and satisfactory disturbance rejection is implemented. The set point optimization improved the nitrogen removal (N-removal) process in terms of EQ and energy costs, resulting in a 75% decrease of pumping energy.