Simulation Study On Influence Of Wastewater From Key Installations In Petrochemical Park On Comprehensive Wastewater Treatment Plant

In this paper,BioWin software is used as a tool to establish a model for the comprehensive wastewater treatment plant in the petrochemical park,calibrate its key parameters and verify the actual measurement,and simulate the scenario of wastewater from key units in the petrochemical park entering the wastewater treatment plant,and analyze the impact of wastewater from key units on the comprehensive wastewater treatment plant in the park.The main results are as follows:?1?The process model of the biological treatment section of the integrated wastewater treatment plant in the typical petrochemical park was established by using the BioWin software.The component parameters of wastewater were measured,and the model was established according to the actual process of wastewater treatment plant.Through sensitivity analysis,the main influencing parameters were identified as heterotrophic bacteria yield coefficient Y_H,heterotrophic bacteria maximum specific growth rate?_H,ammonia oxidizing bacteria maximum specific growth rate?_A.Based on this,the model was corrected.?2?Four key kinetic parameters and chemometrics parameters?heterotrophic yield coefficient Y_H,heterotrophic decay rate b_H,heterotrophic maximum specific growth rate?_H,ammonia oxidizing bacteria maximum specific growth rate?_A?of the sewage treatment plant in the park were measured,and the measured values were 0.717gCOD/gCOD,0.6117d^-1,2.9975d^-1 and 0.7475d^-1,respectively,which were returned to the model for simulation.It was found that the simulation results were similar to the measured values,proving that the measured values were similar.The rationality of parameter correction is given.?3?The simulation of crotonaldehyde wastewater entering the sewage plant in a certain proportion was carried out:the industrial wastewater and crotonaldehyde wastewater were mixed in different proportion,the characteristic component parameters and key kinetic parameters??_A,?_H,b_H,Y_H?were measured,and the parameters were returned to the model for simulation,and the simulated effluent quality was analyzed.The accuracy of the simulation is verified by the actual situation of crotonaldehyde wastewater entering the plant in 2018.It is found that the simulated value of the effluent is highly consistent with the measured value,which reflects the reliability of this simulation method.?4?The characteristic analysis and key parameters of industrial wastewater mixed with different proportion of butyl octanol wastewater and acrylic acid wastewater were carried out,and the measured data were returned to the model for simulation.Compared with the results of key parameters measurement,it is found that the influence of three kinds of wastewater on the yield coefficient of heterotrophic bacteria,the maximum specific growth rate of heterotrophic bacteria and the maximum specific growth rate of ammonia oxidizing bacteria is as follows:crotonaldehyde wastewater>acrylate wastewater>butyl alcohol wastewater.Comparing the effects of different ratios of plant wastewater on effluent,it is found that when the mixing ratios of industrial wastewater and crotonaldehyde wastewater are 500:1,1000:1and 2000:1 respectively,the COD removal rates are 68.07%,72.92%and 82.44%.When the mixing ratios of industrial wastewater and butyl alcohol wastewater are 200:1,500:1 and1000:1 respectively,the COD removal rates are 76.30%,79.85%and 85.60%.When the mixing ratios of industrial wastewater and acrylate wastewater are 150:1,300:1 and 600:1respectively,the COD removal rates are 69.48%,78.06%and 82.71%.When the mixing ratio of butyl octanol wastewater is 1000:1,the COD of simulated biochemical effluent is 83.1mg/L,which can meet the discharge standard after subsequent advanced treatment.