Abstract for: Using System Dynamics to Simulate Biochemical Reactions for Sequential Batch Reactor (SBR) Wastewater Treatment Plant

A system dynamics simulation was developed to explore the removal of various substrates. The substrates include ammonia nitrogen (NH) and nitrate nitrogen (NO) in the presence of particulate organic matter (P) and soluble Biological Oxygen Demand (BOD)5 (S) focused on a Sequential Batch Reactor (SBR) system to ensure compliance to local environmental legislation requirements. Biochemical anoxic and aerobic kinteitcs conditions are assessed and analysed comprehensively during the filling and reaction stages of an SBR system. The kinetics assessment includes the removal rates for oxidation of dissolved organic matter, hydrolysis of particulate organic matter, nitrification of ammonia nitrogen, and denitrification of nitrate nitrogen for all the substrates. All the substrates are analysed based on different anoxic and aerobic fill conditions at constant reaction conditions to evaluate the optimal operating conditions for better performance of an SBR system. The complicated biological reaction rates were successfully simulated using stocks and flows, with valuable insights. The best performance results were recorded when lower anoxic and higher aerobic fill conditions were adopted. The second best results were recorded where higher anoxic and lower aerobic fill conditions were applied. An important outcome was that a single fill condition should not be adopted independently as most typical SBR system design. This filling strategy would result in poor SBR system performance.