Robust Feedback Control Design for a Nonlinear Wastewater Treatment Model

Abstract : In this work we deal with the design of the robust feedback control of wastewater treatment system, namely the activated sludge process. This problem is formulated by a nonlinear ordinary differential system. On one hand, we develop a robust analysis when the specific growth function of the bacterium µ is not well known. On the other hand, when also the substrate concentration in the feed stream s in is unknown, we provide an observer of system and propose a design of robust feedback control in term of recycle rate, in order to keep the pollutant concentration lower than an allowed maximum level s d .