Innovation Research Institute, Shandong Hi-speed Group, Jinan, 250001, China.
Key Lab of Marine Environment and Ecology of Ministry of Education, Ocean University of China, Qingdao, 266100, China.
Chemosphere. 2024 Oct;365:143308. doi: 10.1016/j.chemosphere.2024.143308. Epub 2024 Sep 10.
Anaerobic ammonium oxidation (anammox) is an efficient and economical nitrogen removal process for treating ammonium-rich industrial wastewaters. However, Cu(Ⅱ) and Ni(Ⅱ) present in industrial wastewaters are toxic to anaerobic ammonium-oxidizing bacteria (AnAOB). Unfortunately, the effects of Cu(Ⅱ) and Ni(Ⅱ) on anammox have not been thoroughly investigated, especially when Cu(Ⅱ) and Ni(Ⅱ) coexist. This work comprehensively investigated the individual and combined effects of Cu(Ⅱ) and Ni(Ⅱ) on anammox and revealed the inhibitory mechanisms. With the influent NH-N and NO-N concentration of 230 and 250 mg L, the inhibition thresholds on anammox are 2.00 mg L Cu(Ⅱ), 1.00 mg L Ni(Ⅱ) and 1.00 mg L Cu(Ⅱ) + 1.00 mg L Ni(Ⅱ), and higher Cu(Ⅱ) or Ni(Ⅱ) concentrations resulted in sharp deteriorations of nitrogen removal performance. The inhibition of Ni(Ⅱ) on anammox was mainly attributed to the adverse effect on NiR activity, while the inhibition mechanism of Cu(Ⅱ) seemed to be unrelated to the four functional enzymes, but associated with disruption of cellular and organellar membranes. The behavior of extracellular polymeric substances (EPS) contributed to the antagonistic effect between Cu(Ⅱ) and Ni(Ⅱ) on anammox. In addition, the niche of Candidatus Brocadia and Candidatus Jettenia shifted under the Cu(II) and Ni(II) stress, and Candidatus Jettenia displayed greater tolerance to Cu(II) and Ni(II) stress. In conclusion, this research clarified the combined effect and the inhibitory mechanism of multiple heavy metals on anammox, and provide the guidances for anammox process application in treating high-ammonium industrial wastewaters containing heavy metals.
厌氧氨氧化（anammox）是一种高效且经济的脱氮工艺，可用于处理富含铵的工业废水。然而，工业废水中存在的 Cu（Ⅱ）和 Ni（Ⅱ）对厌氧氨氧化菌（AnAOB）具有毒性。不幸的是，Cu（Ⅱ）和 Ni（Ⅱ）对 anammox 的影响尚未得到彻底研究，特别是当 Cu（Ⅱ）和 Ni（Ⅱ）共存时。本研究全面考察了 Cu（Ⅱ）和 Ni（Ⅱ）单独及联合作用对 anammox 的影响，揭示了抑制机制。进水 NH-N 和 NO-N 浓度分别为 230 和 250mg·L-1，anammox 的抑制阈值为 2.00mg·L-1 Cu（Ⅱ）、1.00mg·L-1 Ni（Ⅱ）和 1.00mg·L-1 Cu（Ⅱ）+1.00mg·L-1 Ni（Ⅱ），更高浓度的 Cu（Ⅱ）或 Ni（Ⅱ）会导致脱氮性能急剧恶化。Ni（Ⅱ）对 anammox 的抑制主要归因于其对 NiR 活性的不利影响，而 Cu（Ⅱ）的抑制机制似乎与四种功能酶无关，而与细胞和细胞器膜的破坏有关。胞外聚合物（EPS）的行为促进了 Cu（Ⅱ）和 Ni（Ⅱ）对 anammox 的拮抗作用。此外，Candidatus Brocadia 和 Candidatus Jettenia 的生态位在 Cu（Ⅱ）和 Ni（Ⅱ）胁迫下发生了转变，Candidatus Jettenia 对 Cu（Ⅱ）和 Ni（Ⅱ）胁迫表现出更强的耐受性。综上所述，本研究阐明了多种重金属对 anammox 的联合作用和抑制机制，为 anammox 工艺在处理含重金属的高氨工业废水中的应用提供了指导。
