NaClO消毒条件下供水系统余氯指标控制的优化

Optimization of Residual Chlorine Control in Water Supply System under NaClO Disinfection Condition

以天津滨海新区某区域供水系统为研究对象,对次氯酸钠(NaClO)代替液氯消毒后引起的出厂水水质变化和供水管网余氯变化进行了分析,以实现对NaClO消毒工艺运行参数的优化控制。结果表明,NaClO代替液氯消毒仅导致出厂水的p H值略有增加;当NaClO平均投加量达到20 mg/L左右时,出厂水余氯范围可保持在0. 70~0. 90 mg/L,管网末梢余氯均满足≥0. 05 mg/L的国家标准要求;对长距离供水区域可采取单独补氯消毒,补氯后出厂水余氯范围应保持在0. 90~1. 10 mg/L,可有效提高该区域的管网末梢余氯。

A regional water supply system in Tianjin Binhai New Area was taken as the research object, and the change of finished water quality and residual chlorine in water supply pipe network caused by the disinfection of sodium hypochlorite （NaClO） in place of liquid chlorine were analyzed, which aimed to optimize the operation parameters of NaClO disinfection process. The results showed that pH value of the finished water was slightly increased when NaC10 was in place of liquid chlorine as the disinfectant. When average dosage of NaClO was 20 mg/L, the residual chlorine of the finished water could be maintained at 0.70 - O. 90 mg/L, and the residual chlorine at the end of the pipe network met the national standard of higher than or equal to 0.05 mg/L. Supplemental chlorination disinfection process could be adopted in long distance water distribution area. The residual chlorine of the finished water should be maintained at 0.90 - 1.10 mg/L after supplemental chlorination disinfection, which could effectively increase the residual chlorine at the end of the pipe network.