Design and Development of a Soft-Sensor for Ammonia Degradation and Nitrite Accumulation in an Activated Sludge Reactor

Abstract

A soft-sensor for on-line estimation of ammonia degradation (α) and nitrite accumulation (β) is proposed in this paper. The soft-sensor has showed a good behavior in the following of trends and has got final values very close to the experimental analysis. Thought this soft-sensor was not conceived for replacing the laboratory analysis, gives α and β estimations for all the instants in between the laboratory sample taking. The data resulting from the laboratory analysis is used to update the model parameters on which the soft-sensor is based on. Furthermore, the model is used to feed an on-line optimization system to look for the pH and O2 set-points whose gives maximum ammonia degradation (α) and nitrite accumulation (β). This optimization system is executed every time that the model parameters are updated.