成都市机动车清洗站洗车污水水质特征分析

Analysis of carwash wastewater from motor vehicle washing stations in Chengdu

本文覆盖成都市全域共采集74个洗车清洗站洗车污水样品,检测了包括pH、水温、色度、悬浮物(SS)、总磷(TP)、总氮(TN)、氨氮、易沉固体、化学需氧量(COD)、五日生化需氧量(BOD)、阴离子表面活性剂(LAS)、石油类、甲醛、挥发酚、苯系物以及铅、镉、汞、铜和镍在内的20项指标参数,并分析了上述指标参数与机动车清洗站所处地域及机动车清洗站所在圈层及清洗站洗车方式、相关设置等的相关性。总体而言,目前成都市机动车清洗站洗车污水的主要污染集中在pH、色度、TP和COD等四个参数指标,各区域检测结果不存在明显的区域差异性,且现今的沉淀池及自动化洗车方式等有利于相关污染物的有效控制。本研究将为机动车洗车污水相关标准和规范的制定提供有效的实验支撑和科学的数据参照,也将进一步有力地推动现有机动车清洗站的科学规范管理,同时对保障水体和人民生命安全具有重要现实意义。

In this work,the wastewater samples were collected from 74 carwash stations covering the whole area of Chengdu city,and 20 kinds of indices including pH,temperature,chromaticity,suspended solids(SS),total phosphorus(TP),total nitrogen(TN),ammonia nitrogen,sinkable solids,chemical oxygen demand(COD),five-day biochemical oxygen demand(BOD),anionic surfactants(LAS),petroleum,formaldehyde,volatile phenols,benzene,lead,cadmium,mercury,copper and nickel were tested.Meanwhile,the correlation between the above test results and the carwash stations including their locations,type of car washing and related facilities were also investigated.The results showed that the pollution mainly derived from four indices including pH,chromaticity,TP and COD,respectively,and there is no apparent correlation between the results and the locations of the carwash stations for sampling.Moreover,the three-step depositing sink and automatic car wash mode are helpful for effectively controlling the pollution.This study will provide experimental and data support to establish related standards or regulations for carwash wastewater discharging,and will also further strongly promote the scientific and standardized management of the motor vehicle washing stations.Meanwhile,this work is also beneficial for guaranteeing the safety of water body and human health.