Modeling And Simulation Of Membrane Bioreactor Model Based On ASM3

Membrane bioreactor (MBR) is a kind of water treatment system with a combination of the membrane separation unit and the bioreactor. This system has the advantages of high biological efficiency, excellent water quality and stability, small device footprint and easy automatic control, etc, but some shortcomings still exist in terms of actual operation. Mathematical models are applied to guarantee the process design and scientific and Reasonable operation of the MBR. Using the ASM3model for the simulation of the MBR can help us better understand and grasp the dynamic response of the MBR process, enabling us to optimize the operation and management of MBR, and to undertake the analysis and evaluation of the factors affecting the operation of MBR. In this thesis, based on the ASM3, an ASM3-MBR simulation system is developed on the MATLAB/Simulink platform which can be applied to the water quality analysis of the MBR reactor effluent.The research includes the establishment of the model, the division of model components, sensitivity analysis and model calibration and verification, etc.The main innovative points and research results are as follows:1. Based on the MATLAB/Simulink platform and the ASM3, regarding the submerged MBR,the visual ASM3-MBR sewage processing simulation system is developed, which has the advantages of intuitive interface, clear meaning, easiness to input data, etc.2. In the process of sensitivity analysis and parameter correction, the author uses the effluent data of the of the submerged MBR under the condition of stable operation. Moreover, the established model is also used in the simulation of the operation effects with the changes of the inlet water quality, the results verify the accuracy of the model.3. Through the sensitivity analysis of the model, it can be concluded that when the parameters change, the parameters of COD simulation values which have higher sensitivity to the changes are: fst,Kx,kH, etc.; the parameters of Ammonia nitrogen simulation values which have higher sensitivity to the changes are:μA, KA,NH, bA,O, etc.; the parameters of TN simulation values which have higher sensitivity to the changes are:YA, bH,O2,YH,O,etc.4. After the steady state simulation of a submerged MBR process and the adjustment of typical values for the parameters of the ASM3model according to the International Water Association, the simulation results are adjusted from the typical values of simulation with the COD error of3.79%, ammonia error of3.79%, TN37.57%error to the corrected values of simulation with the COD error of0.07%, Ammonia error of0.07%of COD and TN error of0.03%.5. The ASM3-MBR model simulation of the treatment effects of MBR is undertaken under different conditions of the inlet water quality, the simulation values of the effluent COD, ammonia nitrogen, total nitrogen are consistent with the relevant measured values.