A STRUCTURED METABOLIC MODEL FOR ANAEROBIC AND AEROBIC STOICHIOMETRY AND KINETICS OF THE BIOLOGICAL PHOSPHORUS REMOVAL PROCESS

A structured metabolic model is developed that describes the stoichiometry and kinetics of the biological P removal process. in this approach all relevant metabolic reactions underlying the metabolism, considering also components like adenosine triphosphate (ATP) and nicotinamide-adenine dinucleotide (NADH(2)) are described based on biochemical pathways. As a consequence of the relations between the stoichiometry of the metabolic reactions and the reaction rates of components, the required number of kinetic relations to describe the process is reduced. The model describes the dynamics of the storage compounds which are considered separately from the active biomass. The model was validated in experiments at a constant sludge retention time of 8 days, over the anaerobic and aerobic phases in which the external concentrations as well as the internal fractions of the relevant components involved in the P-removal process were monitored. These measurements include dissolved acetate, phosphate, and ammonium; oxygen consumption; poly-beta-hydroxybutyrate (PHB); glycogen; and active biomass. The model satisfactorily describes the dynamic behavior of all components during the anaerobic and aerobic phases. (C) 1995 John Wiley and Sons, Inc.