A~2O Process Simulation Study Based On Full Scale Municipal Wastewater Treatment Plant

For the simulation of full scale A2O wastewater treatment plant, this paper identified gross errors of wastewater treatment plant original data, calibrated model parameters, simulated water qualities and aertion changes, and analized sensitivity and uncertainty of model parameters. Main results were as flowing.1. Overlapping mass balance can be used to reconcilate history data of wastewater treatment plant, this method was effective to identify errors of wastewater treatment plant original data. Wasted activated sludge was the most unaccurate parameters in wastewater treatment plant operation and was very important for simulation. In this study, uncertainty of nitrate concentration was identified by overlapping mass balance.2. Nitrification kinetics was systemically studied by analysing field data of plug flow aeration tank. The method was effective not only for non-steady state nitrification system, but also for complete nitrification system. Relative oxygen transfer rate(a) was tested by off-gas test, which was combined with aeration simulation. This method is effective to simulate DO variation.3. Some key parameters were analyzed by single factor disturbance, which was effective to identify sensitivity of model parameters. Monte-Carlo method was used to determine uncertainty of simulaiton parameters, which was based on mathematical statistics and analysis. The method provided a good solution for uncertainty analysis of model.