屋面初期雨水弃流装置的设计及试验

针对暴雨径流及屋面初期雨水水质较差,不能满足雨水利用的要求,采用初期雨水弃流的水质控制技术,设计了一种组合式屋面初期雨水弃流装置.根据雨水污染物冲刷的规律和降雨的强度,确定了所需弃流池的容积；设计中,将截留在弃流装置中的雨水由底部透水部件直接渗入地下；装置结构主要采用再生树脂复合材料,底部透水土工布主要采用骨料和粘结剂的合成材料.试验结果表明:弃流量为3mm时,该装置可以截留屋面初期雨水50％～70％的污染物,以SS、浊度、COD为主,最高的去除率分别达到74.95％,50.00％,60.90％；装置不需要进行雨后管理,只需进行定期维护.

Design and experiment of split-flow device for roof initial rainwater

To make storm runoff and initial rainwater with poor quality meet the requirement of reuse,a combined split-flow device of roof initial rainwater was designed based on water quality control technology.The split-flow cell volume was regulated according to rainwater pollutants scouring law and rainfall intensity.The intercepted rainwater was penetrated directly into ground through the bottom permeable components.The split-flow device was mainly composed of regenerated resin,while the bottom permeable components were made up of aggregate and binder synthetic material.The test results show that with initial rainwater runoff discarding of 3 mm,50%-70% pollutants of SS,turbidity and COD can be intercepted with the highest removal efficiencies of 74.95%,50.00%,60.90%,respectively.The designed device just need regular maintenance without any personnel management after rain.