Modeling sequencing batch reactor operational conditions depending on oxygen concentration

Abstract

Abstract Sequencing batch reactors (SBR) can be used as a fill-and draw activated sludge system for wastewater treatment with considerable operating flexibility and the possibility to conduct experiments under standard conditions and extreme case scenarios. Mathematical modeling and computer simulations provide an opportunity to implement existing wastewater processes in modeling software and evaluate different modifications at low costs and no disturbances for on-going processes of full scale WWTP. Additionally, the used model can be calibrated and validated against experimental data from laboratory scale devices. The aim of this study was to simulate the processes occurring in laboratory scale SBR under different aeration strategies. The results include the analysis of the adaptation period of the activated sludge biomass in the SBR, as well as the case of breakdown of treatment process due to stoppage of raw wastewater inflow and the interruption of the aeration and/or mixing. As a result, it can be stated that the oxygen transfer rate should be incorporated in the calibration of biological nutrient removal model in order to effectively visualize the individual contributions of each process.