State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
Environ Int. 2020 Jun;139:105596. doi: 10.1016/j.envint.2020.105596. Epub 2020 Apr 4.
Nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) coupling to Anaerobic ammonium oxidation (Anammox) provides an opportunity for simultaneous nitrogen removal and methane emissions mitigation from wastewater. However, to achieve high nitrogen removal rate in such a process remains a critical challenge in practical application. This work investigated the interactions between n-DAMO and Anammox in membrane biofilm reactor (MBfR) and then developed operational strategies of MBfR for high rate nitrogen removal from landfill leachate. Initially, influent containing nitrate and ammonium facilitated the development of n-DAMO and Anammox microorganisms in MBfR, but nitrogen removal performance is hard to be further improved even deteriorated. Detailed investigations of interactions among n-DAMO and Anammox microorganisms confirmed that extra addition of nitrite into MBfR fed with nitrate and ammonium not only stimulated the activities of Anammox bacteria, but also enhanced the activities of n-DAMO archaea from 172.3 to 356.9 mg NO-N L d. Functional gene analysis also indicated that mcrA and hzsA genes increased after nitrite addition. Based on this finding, influent containing NO, NO and NH enabled nitrogen removal rates of MBfR increase from 224.9 to 888.2 mg N L d. Finally, nitrate in the influent was gradually replaced with nitrite to mimic the effluent from partial nitriation of landfill leachate, but maintain the nitrate availability for n-DAMO archaea through increasing nitrate production from Anammox. These operation strategies enabled MBfR achieve the steady state with a nitrogen removal rate of 6.1 kg N m d. Microbial community analysis revealed n-DAMO archaea, n-DAMO bacteria and Anammox bacteria jointly dominated the biofilm, and their relative abundance dynamically shifted with feeding regime. This work provides promising operational strategies for high rate of nitrogen removal from landfill leachate through integrating n-DAMO and Anammox process.
硝酸盐/亚硝酸盐依赖型厌氧甲烷氧化（n-DAMO）与厌氧氨氧化（Anammox）偶联为同时去除废水中的氮和减少甲烷排放提供了机会。然而，在实际应用中，实现高氮去除率仍然是一个关键挑战。本研究在膜生物膜反应器（MBfR）中考察了 n-DAMO 与 Anammox 之间的相互作用，然后开发了 MBfR 的操作策略，以实现从垃圾渗滤液中高去除率的氮。最初，含有硝酸盐和铵盐的进水促进了 MBfR 中 n-DAMO 和 Anammox 微生物的生长，但氮去除性能难以进一步提高，甚至恶化。n-DAMO 和 Anammox 微生物之间相互作用的详细研究证实，向同时含有硝酸盐和铵盐的 MBfR 中额外添加亚硝酸盐不仅刺激了 Anammox 细菌的活性，还将 n-DAMO 古菌的活性从 172.3 提高到 356.9 mg NO-N L d。功能基因分析还表明，添加亚硝酸盐后 mcrA 和 hzsA 基因增加。基于这一发现，进水含有 NO 、NO 和 NH 使 MBfR 的氮去除率从 224.9 增加到 888.2 mg N L d。最后，逐渐用亚硝酸盐替代进水中的硝酸盐，以模拟来自垃圾渗滤液部分硝化的出水，但通过增加 Anammox 产生的硝酸盐来保持 n-DAMO 古菌的硝酸盐可用性。这些操作策略使 MBfR 达到了稳定状态，氮去除率为 6.1 kg N m d。微生物群落分析表明，n-DAMO 古菌、n-DAMO 细菌和 Anammox 细菌共同主导生物膜，其相对丰度随进料方式动态变化。本研究为通过整合 n-DAMO 和 Anammox 工艺从垃圾渗滤液中实现高去除率的氮提供了有前景的操作策略。
