Unknown-input observer for disturbance and state estimation of an activated sludge waste water treatment process

This paper propose the application of an unknown-input observer for a reduced linear model of an activated sludge wastewater treatment process, functioning in an alternating phases (aerobic-anoxic). The aim of this observer is to estimate both the unknown input and the state of system to better developing the control strategies and monitor its dynamics. It can be mentioned that in view of the linear reduced model structure, an observer is formed for each phase. The observer's performances are evaluated by using simulation and experimental data. Its good results have been also proved by comparing them to the ones of another observer.