Study On Interception And Storage Of Initial Rainwater On Polluted Pavement In Industrial Park

Industrial parks generally occupy large areas,and facility maintenance and management are difficult.During the production process,chemicals and other substances may"run and drip",causing pollutants to exist around the park in solid,liquid,and gaseous forms.The rain dissolves exhaust gas in the air during the initial landing,and after landing,it washes the polluted road surface,pipe and channel sediments,etc.,making it contain a lot of pollutants.Various pollution loads are collected in the rainwater runoff,causing serious pollution to the surrounding water bodies,so measures need to be taken for governance.This article takes"The initial rainwater on polluted pavement in a production area of an industrial park in Hubei Province"as a research case,analyzes the initial rainwater pollution characteristics of the polluted road in the park and determines the initial rainwater interception scheme and interception volume.Based on underlying surface and the actual situation of the pipe network,the SWMM model is established to simulate the initial rainwater quality and quantity.Design the initial rainwater interception storage tank to control the environmental pollution caused by the initial rainwater,and study the regulation and storage effect of the interception storage tank under different return periods.Firstly,based on the basic situation of the drainage system of the industrial park,the necessity of initial rainwater interception was analyzed,sampling points were selected and water sample data were collected in three rainfall events for detection,mainly detecting rainfall,rainfall intensity,runoff flow,p H value and five other pollution indicators(SS,COD_Cr,NH₃-N,TP,Cl^-),the results show that the concentration of most pollutants exceeds the standard requirements,and measures need to be taken to deal with them;Through the M（V）dimensionless curve analysis,it is known that the pollution loads have an initial scour effect,and the initial polluted rainwater needs to be intercepted,and the interception volume is the top 45%of the rainwater runoff;Based on the Pearson correlation coefficient analysis,it can be seen that there is a linear correlation between SS and other pollutants,and the rainwater storage tank with chemically enhanced treatment function can be used to treat the initial rainwater.Secondly,based on the measured rainfall water quality and quantity datas of the industrial park,the SWMM model was constructed,and the catchment area and pipeline network of the study area were generalized,and the production area was generalized into 42 sub-catchment areas,46 pipe channels,46 hinge points and 1 discharge port;And slecting the flow and water quality data of the rainfall on October 2,2020 to calibrate the parameters of the model.The results show that the established SWMM model is reliable and accurate.Finally,the industrial park is divided into three areas from north to south to collect initial rainwater,each area has an area of9.5ha,15.1ha,and 15.4ha.The use of intelligent integrated interception lift wells will lift the rainwater interception with high initial pollution loads to the storage tank for treatment;Establishing rainfall process lines under different return periods,combining relevant specifications and comprehensively consider the actual situation of the park,selecting the return period P=0.5a,and calculate the storage tank volume to be 3600m³.And the volume is able to adapt to the regulation of the total intercepted rainwater of1500～5800m³;Based on the SWMM simulation statistics,the total change of the pollutants at the discharge outlet and the interception efficiency before and after the initial rainwater interception in each return period,the results show that the interception efficiency reaches more than 40%,indicating that the interception storage tank has good regulations and storage effects.