基于SWMM模型的截流倍数环境效应分析

由于对改造建设的重视程度、时序安排、经济条件、改造难度等许多主观和客观因素的限制,许多城市老城区的合流制排水系统保留至今。采用SWMM水力水质模型,对城市合流区的污染物削减情况进行模拟评价,以期为合流制排水系统的截流倍数取值及建设方向提供参考。结果表明,当截流倍数n≥2时,合流制排水系统即可达到分流制排水系统的污染物截流效果;但只有当截流倍数n≥5时,合流制排水系统才能达到分流制排水系统的污染物削减效果。城市合流区需尽快进行合改分建设,或加大末端处理设施的建设。

Environmental Effect Analysis of Interception Ratio Based on SWMM Model

Due to the limitation of subjective and objective factors,such as the importance of reconstruction,time sequence,economic condition and reconstruction difficulties,etc,the combined sewer system in many old urban districts has been preserved till now.In this study,SWMM model was used to simulate and evaluate pollutants reduction in urban combined sewer area,which aimed to provide reference for interception ratio and construction direction of combined sewer system.When the interception ratio was no less than 2,the combined sewer system could achieve the pollutants interception performance equal to that of the separate sewer system.However,the combined sewer system achieved the pollutants reduction performance equal to that of the separate sewer system only when the interception ratio was no less than 5.In urban combined sewer area,it is necessary to transform the combined sewer system into separate sewer system as soon as possible,or increase the construction of terminal treatment facilities.