The current model of the full-scale wastewater treatment plant model in Eindhoven uses a state-of-the-art model for the biological processes (ASM2d) and is calibrated for C-and N-removal in dry weather. However, for the "Kallisto" project, which is an innovation programme aiming at a smart improvement of the surface water quality of the river Dommel by applying cost effective integrated system measures, the WWTP model needs to be improved to predict the WWTP performance under all conditions foreseen in the scenarios (e.g. storm events). A project approach was developed with parallel improvements in the different submodels, based on the interaction between submodels and the availability of several on-line sensors in influent, in-process and effluent. This is in contrast to most WWTP modelling studies, where focus is only on one submodel. It should lead to a well-balanced dynamic model that is able to predict WWTP behaviour under various conditions and that will be included in the integrated model, which will serve as an important decision support tool. Keywords urban wastewater system, dynamic modelling, WWTP optimization
INTRODUCTIONOverall improvement of efficiency, increasingly stringent effluent discharge limits, the aim for a better surface water quality, minimization of energy use and greenhouse gas emissions are current drivers for the optimization of urban wastewater systems and operational strategies of wastewater treatment plants (WWTPs). In this respect, the use of dynamic models has already proven to be of great value. Indeed, a model with high predictive power allows testing of different optimisation strategies without disrupting the actual operation of the plant i.e. without the risk of losing biomass or violating discharge permits. Waterboard De Dommel (WDD, The Netherlands) has shown long-term interest in the development and use of dynamic models, which resulted in a calibrated dynamic model (including COD, N and P removal) of WWTP Haaren (Sin et al.,2008). Building further on the gained knowledge, a full-scale model of Eindhoven was calibrated and validated for dry weather including C and N removal (Nopens et al., 2010). This model is used as basis in the wastewater treatment plant modelling part of the current "Kallisto" project, which studies the integrated urban water system in the water cluster Eindhoven.