Simulation of a time dependent activated sludge wastewater treatment plant

Abstract A dynamic mathematical model has been developed for a general activated sludge wastewater treatment plant. The model includes a primary settler, aeration tank, and clarifier-thickener, each of which is represented by various configurations of a general tanks-in-series model. With the aid of the model, it was possible to simulate simultaneously the diurnal response of a number of significant variables including dissolved BOD, suspended solids, dissolved volatile solids, active mass, inert mass, soluble nonbiodegradable mass, Nitrosomonas mass, Nitrobacter mass, ammonium, nitrite, nitrate and dissolved oxygen. The equations for the model as well as the results of plant simulations using the model and a sensitivity analysis are presented.