不同pH条件下市政供水管材球墨铸铁早期电化学腐蚀特性  

Electrochemical corrosion characteristics of ductile iron used for municipal drinking water supply pipeline under different pH conditions

作　　者：王悦 牛佳 刘玉 张小闽 刘羽庄 陈祥钰 WANG Yue;NIU Jia;LIU Yu;ZHANG Xiaomin;LIU Yuzhuang;CHEN Xiangyu(Fuzhou Water Quality Monitoring Co.,LTD.,Fuzhou,Fujian 350007,China;Fujian Engineering Research Center of Water Pollution Control and System Intelligence Technology,College of Ecological Environment and Urban Construction,Fujian University of Technology,Fuzhou,Fujian 350118,China;College of Environment and Safety Engineering,Fuzhou University,Fuzhou,Fujian 350108,China)

机构地区：[1]福州水质监测有限公司,福建福州350007 [2]福建理工大学生态环境与城市建设学院,福建省水污染阻控与系统智能技术工程研究中心,福建福州350118 [3]福州大学环境与安全工程学院,福建福州350108

出　　处：《福州大学学报（自然科学版）》2024年第5期604-611,共8页Journal of Fuzhou University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(52000032);福建省自然科学基金资助项目(2023J01933);福州大学贵重仪器设备开放测试基金资助项目(2023T014);福州市自来水公司合作项目(GY-H-21258)。

摘　　要：为解决早期供水管道腐蚀造成的水质恶化问题,探究不同pH值(6、7、8)条件下球墨铸铁的腐蚀特性,利用极化曲线和阻抗谱监测电化学腐蚀过程,并探讨腐蚀对水质和腐蚀垢组成的影响.结果表明,pH值为6条件下水中TDS、电导率、拉森指数显著高于其他条件(P<0.05),而朗格利尔指数显著低于pH值为8的条件(P<0.05),即pH值为6时腐蚀倾向最高.金属表面腐蚀垢产物类型的研究表明不同pH值条件下腐蚀产物类型均为γ-FeOOH、β-FeOOH、Fe_(2)O_(3)、Fe_(3)O_(4),但去离子水对照组腐蚀产物仅包括γ-FeOOH.对腐蚀过程研究发现,不同pH值条件下球墨铸铁腐蚀电流密度(2.54~0.13μA·cm^(-2))随着时间呈先快速增大后逐渐减小的特点,且第1天时pH值为6腐蚀电流密度最高(2.54μA·cm^(-2)).由此可见,尽管市政管道早期都会发生腐蚀,但是当管网水的pH值偏酸性,即pH值为6条件下,腐蚀倾向最高、腐蚀速率最快.In order to solve the deterioration of water quality caused by water supply pipeline corrosion during early stage,the corrosion characteristics of ductile cast iron,under different pH(6,7,8)conditions were explored.The electrochemical corrosion process was monitored by polarization curve and impedance spectrum.The influence of corrosion on water quality and the composition of corrosion scale were discussed.The results showed that the TDS,conductivity and Larsen index of pH 6 treatment were significantly higher than those of other treatments(P<0.05).While the Langelier index was significantly lower than that of pH 8 treatment(P<0.05),indicating that the corrosion tendency was the highest when pH was 6.The study on the types of corrosion scale products on the metal surface showed that the types of corrosion products under different pH conditions areγ-FeOOH,β-FeOOH,Fe_(2)O_(3) and Fe_(3)O_(4),but the corrosion products of the deionized water control group only includeγ-FeOOH.Study on the corrosion process showed that the corrosion current density(2.54 to 0.13μA·cm^(-2))of ductile cast iron under different pH treatments increased rapidly and then decreased gradually.The corrosion current density was the highest(2.54μA·cm^(-2))at pH 6 on the first day.It can be seen that although the municipal pipeline will be corroded in the early stage,when the pH of the water is acidic,i.e.,pH 6,the corrosion tendency will be the highest and the corrosion rate be the fastest.

关 键 词：市政供水 球墨铸铁管 腐蚀 PH值 微生物 电化学 

分 类 号：TU991.38[建筑科学—市政工程]