School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
Chemosphere. 2022 Aug;301:134652. doi: 10.1016/j.chemosphere.2022.134652. Epub 2022 Apr 18.
Changes of drinking water quality can lead to iron release in drinking water distribution systems (DWDSs), which is one of the most important reasons for the deterioration of tap water quality. The objective of this study was to investigate the effects of nitrate on the iron release and characteristics of corrosion scales and bacterial communities in DWDSs using simplified pipe section reactors. With nitrate addition, the percentages of goethite (α-FeOOH), hematite (FeO), and lepidocrocite (γ-FeOOH) in scales were decreased, whereas those of magnetite (FeO) were increased. The growth of nitrate-reducing bacteria (NRB) was promoted significantly, with the fractions of 25.70% and 23.79% in the steel and cast iron pipes, respectively. Approximately 3.40% of iron-reducing bacteria (IRB) were reduced in both pipes. Moreover, under higher nitrate levels, iron release was inhibited obviously. The maximum decreased percentages of total iron in the steel and cast iron pipes were 44.90% (with 10.00 mg/L NO-N) and 88.29% (with 30.00 mg/L NO-N), respectively. This study may be helpful for improving drinking water supply safety.
水质变化会导致饮用水分配系统（DWDS）中释放铁，这是导致自来水水质恶化的最重要原因之一。本研究旨在使用简化管段反应器研究硝酸盐对 DWDS 中铁释放以及腐蚀垢特征和细菌群落的影响。添加硝酸盐后，样品中针铁矿（α-FeOOH）、赤铁矿（FeO）和纤铁矿（γ-FeOOH）的比例降低，而磁铁矿（FeO）的比例增加。硝酸盐还原菌（NRB）的生长明显受到促进，在钢管和铸铁管中的分数分别为 25.70%和 23.79%。此外，两种管道中的铁还原菌（IRB）分别减少了约 3.40%。而且，在较高的硝酸盐水平下，铁的释放受到明显抑制。在钢管和铸铁管中，总铁的最大减少百分比分别为 44.90%（10.00mg/L 的 NO-N）和 88.29%（30.00mg/L 的 NO-N）。这项研究可能有助于提高饮用水供应安全性。
