State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China; College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China; College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
Sci Total Environ. 2023 Oct 15;895:165034. doi: 10.1016/j.scitotenv.2023.165034. Epub 2023 Jun 23.
Microbially-induced corrosion (MIC) is unstoppable and extensively spread throughout drinking water distribution systems (DWDSs) as the cause of pipe leakage and deteriorating water quality. For maintaining drinking water safety and reducing capital inputs in pipe usage, the possible consequences from MIC in DWDSs is still a research hotspot. Although most studies have investigated the effects of changing environmental factors on MIC corrosion, the occurrence of MIC in DWDSs has not been discussed sufficiently. This review aims to fill this gap by proposing that the formation of deposits with microbial capture may be a source of MIC in newly constructed DWDSs. The microbes early attaching to the rough pipe surface, followed by chemically and microbially-induced mineral deposits which confers resistance to disinfectants is ascribed as the first step of MIC occurrence. MIC is then activated in the newly-built, viable, and accessible microenvironment while producing extracellular polymers. With longer pipe service, oligotrophic microbes slowly grow, and metal pipe materials gradually dissolve synchronously with electron release to microbes, resulting in pipe-wall damage. Different corrosive microorganisms using pipe material as a reaction substrate would directly or indirectly cause different types of corrosion. Correspondingly, the formation of scale layers may reflect the distribution of microbial species and possibly biogenic products. It is therefore assumed that the porous and loose layer is an ideal microbial-survival environment, capable of providing diverse and sufficient ecological niches. The usage and chelation of metabolic activities and metabolites, such as acetic, oxalic, citric and glutaric acids, may lead to the formation of a porous scale layer. Therefore, the microbial interactions within the pipe scale reinforce the stability of microbial communities and accelerate MIC. Finally, a schematic model of the MIC process is presented to interpret MIC from its onset to completion.
微生物诱导腐蚀（MIC）在饮用水分配系统（DWDS）中无处不在且无法控制，是导致管道泄漏和水质恶化的主要原因。为了确保饮用水安全并降低管道使用成本，DWDS 中 MIC 的潜在后果仍然是一个研究热点。尽管大多数研究都探讨了环境因素变化对 MIC 腐蚀的影响，但 DWDS 中 MIC 的发生尚未得到充分讨论。本综述旨在通过提出微生物捕获形成的沉积物可能是新建造的 DWDS 中 MIC 的来源来填补这一空白。微生物早期附着在粗糙的管道表面，随后是化学和微生物诱导的矿物沉积物，这些沉积物赋予了消毒剂的抗性，这被认为是 MIC 发生的第一步。然后，在新建造的、有活力的和可接近的微环境中，MIC 被激活，同时产生细胞外聚合物。随着管道使用时间的延长，贫营养微生物缓慢生长，金属管道材料与电子一起逐渐释放到微生物中，导致管壁损坏。不同的腐蚀性微生物将管道材料用作反应底物，会直接或间接导致不同类型的腐蚀。相应地，水垢层的形成可能反映了微生物物种的分布和可能的生物产物。因此，可以假设多孔和疏松的层是微生物生存的理想环境，能够提供多样且充足的生态位。代谢活动和代谢产物（如乙酸、草酸、柠檬酸和戊二酸）的利用和螯合作用可能导致多孔水垢层的形成。因此，管道水垢内的微生物相互作用增强了微生物群落的稳定性并加速了 MIC。最后，提出了一个 MIC 过程的示意图模型，以解释从开始到完成的 MIC 过程。
