Model-based evaluation of oxygen consumption in a partial nitrification–Anammox biofilm process

Previous modelling studies indicated that DO was a key factor controlling a partial nitrification–Anammox biofilm process (CANON). As a design parameter, therefore, aeration becomes critical in engineering. Aeration depends on oxygen consumption (OC) taking place in the CANON system which is determined by nitrification, ordinary denitrification, Anammox and even biofilm thickness. Due to the presence of substrate gradients in a biofilm, the amount of OC is difficult to assess with experiments. For that reason, modelling technique was used here to evaluate OC with an expanded CANON model with heterotrophic growth/denitrification involved. Simulations demonstrated that different process/biofilm parameters created different curves of OC, which could help engineers or operators have a better insight into the topic of OC in process design or practical operation.