摘要
随着各地高品质水工程的推进,淘汰劣质管材已成为各供水企业的普遍共识。余氯是末端供水的重要指标,但是目前各供水企业对于各种管材对余氯的影响差异以及影响机理尚不明确,不利于换管选材的开展。文中通过试验分析了小口径管道中余氯衰减的主要影响因素。在消除水体主反应耗氯的情况下对各类管材的耗氯能力进行了比较,并通过试验测得各管道的管壁反应耗氯系数。此外,结合各主流管道耗氯理论对管壁耗氯反应的机理进行分析。试验表明,304、316不锈钢的余氯衰减显著低于镀锌钢管,并且不恰当焊接的不锈钢管道耗氯程度甚至高于镀锌钢管。根据试验结果以及前人提出的余氯衰减的机理模型,总结出小口径管道余氯衰减的基本模式,分析可知铁氧化成三价铁的过程是管壁反应耗氯的主要来源,铁质的暴露程度对于管道耗氯具有决定性的影响,并在实际管道供水末端实地检测水样余氯验证了理论。结论表明,小口径管道中管壁反应耗氯占了总体耗氯的绝大部分,并且铁质是管壁反应的主要因素。各供水企业应选择不锈钢材质或塑料等材质的管道。
With the promotion of high-quality water projects,it has become a consensus to eliminate inferior pipes for water supply enterprises.Residual chlorine is an important indicator of end-of-pipe water supply,but at present,the difference and mechanism of the impact of various pipes on residual chlorine in water supply enterprises are not clear,which is not conducive to the development of pipe replacement and material selection.In this paper,the main influencing factors of residual chlorine attenuation in small-diameter pipeline were analyzed through experiments.Under the condition of eliminating the chlorine consumption of main reaction in water body,the chlorine consumption capacity of various pipes was compared,and the chlorine consumption coefficient of pipe wall reaction was measured through tests.The mechanism of the chlorine consumption reaction on the pipe wall was analyzed based on the chlorine consumption theory of the mainstream pipes.The test showed that the residual chlorine attenuation of 304 and 316 stainless steel was significantly lower than that of galvanized steel pipe,and the chlorine consumption of improperly welded stainless steel pipe was even higher than that of galvanized steel pipe.According to the test results and the mechanism model of residual chlorine attenuation proposed by the predecessors,the basic mode of residual chlorine attenuation in small diameter pipeline was summarized.The analysis showed that the process of iron oxidation to ferric iron was the main source of chlorine consumption in the reaction of pipe wall,and the exposure degree of iron had a decisive impact on the chlorine consumption of pipeline.The theory was verified by detecting residual chlorine in the water sample at the end of actual pipeline water supply.The conclusion showed that the chlorine consumption of pipe wall reaction accounts for the majority of the total chlorine consumption in small diameter pipes,and iron was the main factor of pipe wall reaction.Each water supply enterprise shall select stainless ste
作者
钱勇
王子祎
QIAN Yong;WANG Ziyi(Suzhou Water Supply Co.,Ltd.,Suzhou 215002,China)
出处
《净水技术》
CAS
2023年第8期180-189,共10页
Water Purification Technology
基金
住房和城乡建设部研究开发项目(2021-K-131)
苏州市科技计划项目(SS2019040)。
关键词
余氯
管网末梢
衰减模型
管材
水力模型
residual chlorine
pipe network end
attenuation model
pipe material
hydraulic model
