Hao Guo , Rui Wang , Menghan Jiang , Yimei Tian , Yapeng Jin , Weigao Zhao , Chenwan Wang , Jianhua Yin
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引用次数: 0
Abstract
The electrochemical corrosion of ductile pipes (DPs) in drinking water distribution systems (DWDS) has a crucial impact on cement-mortar lining (CML) failure and metal release, potentially leading to drinking water quality deterioration and posing a risk to public health. An in-situ scanning vibrating electrode technique (SVET) with micron-scale resolution, microscopic scale detection and water quality analysis were used to investigate the corrosion behavior and metal release from DPs throughout the whole CML failure process. Metal pollutants release occurred at three different stages of CML failure process, and there are potential risks of water quality deterioration exceeding the maximum allowable levels set by national standards in the partial failure stage and lining peeling stage. Furthermore, the effects of water chemistry (Cl−, SO42−, NO3−, and Ca2+) on corrosion scale growth and iron release activity, were investigated during the CML partial failure stage. Results showed that the CML failure process in DPs was accelerated by the autocatalysis of localized corrosion. Cl− was found to damage the uncorroded metal surface, while SO42− mainly dissolved the corrosion scale surface, increasing iron release. Both the oxidation of NO3− and selective sedimentation of Ca2+ were found to enhance the stability of corrosion scales and inhibit iron release.
期刊介绍:
The Journal of Environmental Sciences is an international journal started in 1989. The journal is devoted to publish original, peer-reviewed research papers on main aspects of environmental sciences, such as environmental chemistry, environmental biology, ecology, geosciences and environmental physics. Appropriate subjects include basic and applied research on atmospheric, terrestrial and aquatic environments, pollution control and abatement technology, conservation of natural resources, environmental health and toxicology. Announcements of international environmental science meetings and other recent information are also included.