重庆市典型城镇污水处理厂进水水质特征研究

Study on Characteristics of Influent Water Quality of Typical Urban Wastewater Treatment Plants in Chongqing

选取重庆市272座典型城镇污水处理厂,利用实际监测数据,分析了进水化学需氧量、五日生化需氧量、氨氮、总氮、总磷等主要因子浓度分布特征以及进水水质组成特性。结果表明,重庆市城镇污水处理厂进水COD、BOD_(5)、NH_(3)-N、TN和TP平均浓度分别为158.28 mg∕L、77.27 mg∕L、29.27 mg∕L、39.90 mg∕L和3.65 mg∕L,与其他地区相比,重庆市城镇污水处理厂进水COD和BOD_(5)平均浓度较低,但总氮、氨氮和总磷平均浓度较高。进水BOD_(5)∕COD比值处于0.4~0.6,平均值为0.488,表明污水的可生化性好。进水BOD_(5)∕TN比值平均值为2.28,分布在1~2区间的概率为44.9%,表明污水处理厂普遍存在反硝化碳源不足的情况。进水BOD_(5)∕TP比值平均值为23.56,大于20的概率仅为48.3%,表明有超过一半的城镇污水处理厂难以满足生物除磷的要求。进水TN∕TP比值平均值为10.8,大于5的概率为93.4%,表明进水氮、磷可满足微生物生长需求。

The concentration distribution characteristics of influent factors such as COD,BOD_(5),NH_(3)-N,TN and TP and the composition characteristics of influent water quality were analyzed based on the actual monitoring data of 272 typical urban wastewater treatment plants in Chongqing.The results showed that the average concentrations of COD,BOD_(5),NH_(3)-N,TN and TP in the influent of Chongqing wastewater treatment plants were 158.28 mg∕L,77.27 mg∕L,29.27 mg∕L,39.90 mg∕L and 3.65 mg∕L.The average concentrations of COD and BOD_(5)in the influent of Chongqing wastewater treatment plants are low,but the average concentrations of TN,NH_(3)-N and TN are high.The BOD_(5)∕COD ratio of influent water ranges from 0.4 to 0.6,with an average of 0.488,indicating that the wastewater has good biodegradability.The average BOD_(5)∕TN ratio of influent water was 2.28,and the probability of distribution was 44.9%in the range of 1~2,indicating that there was insufficient denitrifying carbon source in wastewater treatment plants.The average BOD_(5)∕TP ratio of influent water was 23.56,and theprobability of greater than 20 was only 48.3%,indicating that more than half of urban wastewater treatment plants could not meet the requirements of biological phosphorus removal.The average TN∕TP ratio of influent water was 10.8,and the probability of greater than5 was 93.4%,indicating that nitrogen and phosphorus in influent could meet the needs of microbial growth.