STRUCTURAL IDENTIFIABILITY OF BIOKINETIC MODELS OF ACTIVATED-SLUDGE RESPIRATION

This paper deals with the identifiability of parameters of kinetic mod els describing the activated sludge process. The main concern of the p aper is to present important aspects of the structural identifiability properties. The identifiability analysis is based on the availability of only on-line oxygen uptake rate data (given by a novel respirograp hic biosensor). Four model candidates (exponential, Monod, double Mono d and modified IAWQ No. 1) are considered. Two different methods (Tayl or series expansion, and transformation of the nonlinear model into a model linear-in-the-parameters) are considered, their advantages and d rawbacks are illustrated with the four kinetic models. For each model it is found that only a smaller set of the original parameters are str ucturally identifiable on the basis of oxygen uptake rate data only.