Modeling the competition between floc-forming and filamentous bacteria in activated sludge waste water treatment systems—II. A prototype mathematical model based on kinetic selection and filamentous backbone theory

In this paper a prototype mathematical model is introduced which describes the growth of flocs and filaments in activated sludge waste water treatment systems. The model is based on both kinetic selection and filamentous backbone theory. A stability analysis of the model is performed and it is shown that this model, in contrast with mathematical models only based on kinetic selection theory, is able to describe coexistence of both flocs and filaments for a wide range of dilution rates. Afterwards the model is extended in order to describe a standard activated sludge waste water treatment system.