水质化学组分变化对管道铁释放及管垢特征的影响  

Effect of Water Chemistry Changes on Iron Release and Corrosion Scale Properties of Old Cast Iron Pipes

作　　者：杨帆[1] 石宝友[1] 王东升[1] 顾军农 曹楠 

机构地区：[1]中国科学院生态环境研究中心环境水质学国家重点实验室,北京100085 [2]北京市自来水集团有限责任公司水质监测中心,北京100192

出　　处：《中国给水排水》2012年第23期59-64,共6页China Water & Wastewater

基　　金：国家自然科学基金资助项目(51178450);国家水体污染控制与治理科技重大专项(2009ZX07424-003;2009ZX07423-004);北京市教育委员会重点学科共建项目

摘　　要：采集了北方某市长期通地下水区域的铸铁管道样品,应用响应面法研究了几个主要水质化学参数变化对管网铁释放的影响,并利用X射线衍射分析(XRD)、X射线荧光光谱分析(XRF)、比表面分析和扫描电镜能谱分析(SEM-EDX)等手段表征了管道内表面的管垢结构和组成特征,探讨了水质化学组分变化对管垢特征的影响。研究发现,该管道铁的释放量与水的拉森指数具有正相关关系,而与余氯水平无显著相关性。采集之初铸铁管的腐蚀产物包括Fe3O4(磁铁矿)、α-FeOOH(针铁矿)、γ-FeOOH(纤铁矿)、FeCO3(菱铁矿)和β-FeOOH(四方纤铁矿);通入拉森指数较高的水后,腐蚀产物中出现了Fe2O3(赤铁矿)和Fe6(OH)12CO3(绿锈)等新成分,并且管垢中Fe3O4的含量明显增加,α-FeOOH的含量明显降低,β-FeOOH消失。铁释放量较高管段中管垢的比表面积和孔容比铁释放量较低管段中管垢的大。Cast iron pipe sections ot hlstoncally transporting groundwater in a city ol North Idhina were collected, and the effect of some major water quality parameters on the iron release was investigated by response surface methodology. The structural properties and chemical composition of the internal cor- rosion scale were characterized using XRD, XRF, specific surface area analysis and SEM-EDX, and the effect of water chemistry changes on corrosion scale was studied. The results showed that the iron release from the pipe sections was positively correlated to Larson ratio （LR） , but there was no significant rela- tionship between iron release and residual chlorine concentrations. The internal corrosion scales of origi- nally collected pipe sections were constituted of Fe3 04 （ magnetite ）, β-FeOOH （ goethite）, y-FeOOH （lepidocrocite）, FeCO3 （siderite） and β-FeOOH （akaganeite）. After contacting water with higher LR, Fe203 （hematite） and Fe6 （OH）12 CO3 （green rust） were detected, β-FeOOH disappeared, meanwhilethe percentage of Fe304 increased and thatvolume of corrosion scales from higher ironscales from lower iron release pipe sections.of y-FeOOH decreased. The specific surface area and pore release pipe sections were greater than those of corrosion

关 键 词：管网水质 铁释放 管垢特征 响应面法 拉森指数 

分 类 号：TU991.33[建筑科学—市政工程]