Lattice Boltzmann simulation of nitrification process in an aeration tank

The inlet wastewater velocity and air flow rate in the aeration tank are key parameters that directly affect nitrification efficiency. A lattice Boltzmann method (LBM) model was created to simulate how species concentrations change under different wastewater inlet velocities and air flow rates in the nitrification zone of an anaerobic/oxic bioreactor. The simulation used lattice Boltzmann equations representing mass conservation, momentum conservation and mass transport equations, with both macroscopic and microscopic boundary conditions matching actual wastewater treatment conditions. The simulation results show good agreement with existing literature while providing new data on ammonium and nitrate concentration changes across varying influent flow rates and aeration rates. This model demonstrates the LBM’s potential for wider use in biological reactor optimisation to achieve energy savings and improved wastewater treatment efficiency.