Optimization Of The Adjusting Volume Of Combined Sewer Overflow For Pollution Control

Combined sewer overflow?CSO?directly emissions causing serious pollution to urban water environment,CSO control gradually become the focus of attention problems,research has shown that storage pool has significant effects on controlling the CSO pollution,and it has better practicability and operability,while theories and research about volume design of CSO storage pool related is insufficient,still need to be further discussed.This paper analyze the formation process of overflow and calculated using the"rain"type of Chicago confluence system under different return period of the overflow ofwaterprocessline,the water quality model C^*[V_nAC?t?]=?+V_nAC?t?·{Y^*Exp[-k·V_nAC?t?]+?^*} is used to predict the concentration of pollutants under different rainfall intensity change process,with pollution control as the goal,through the water quality model calculation under different return period storage pool best stop intercept time t_i,according to the time of calculation is used to control pollution of CSO storage pool volume V=integral from n=0 to MAX{t_i=f⁽-10(C_i??/1-?_i)}Q?t?dt.Order a study about combined sewer system in chongqing Yuanboyuan as research object,through field monitoring and the main features and analyses the CSO pollution events rainfall in the CSO change law of pollutant concentration,and analyzes the different rainfall conditions on the CSO pollution.Studies have shown that rainfall type has great influence on the overflow wastewater quality,rainfall intensity is bigger,the earth's surface and pipe flushing action is obvious,particle pollutants SS,COD concentration increase pollution is more serious;There was a peak in the water quality of CSO,and there was a difference in the time between the peak of pollutants in different rainfall intensity,but it was mostly concentrated in 10-45min,and the most dense at 20min.And make the CSO of chongqing Yuanboyuan as an example to carried on the analysis of the intercept time and storage tank volume calculation.The efficiency study of the storage pool designed by the calculation method of this paper is carried out by using the SWMM model.Through example this paper introduces the application of SWMM software build confluence pipe drainage system in the process,and will be in chongqing in 2005 rainfall data input model analysis efficiency of storage pool overflow pollution control,and through to the P=0.25,P=0.5,P=1under the three return period of pipe network,to simulate the overflow analysis storage pool in the efficiency of the return period of CSO pollution under control.