亚硝酸盐型厌氧甲烷氧化过程与应用研究进展

A Review of Study on Nitrite-dependent Anaerobic Methane Oxidation Process and Its Application

亚硝酸盐型厌氧甲烷氧化(nitrite-dependent anaerobic methane oxidation,N-DAMO)是指以亚硝酸盐为电子受体将甲烷厌氧氧化为二氧化碳的微生物生化反应过程。此反应是偶联碳氮循环的关键环节,是微生物碳氮循环的新内容,它的发现对于全球的碳氮物质循环具有重要贡献。基于此,文章概述了N-DAMO过程的生化反应机理;总结了N-DAMO菌富集培养过程中的活性影响因素:NO2^--N浓度为2.40 mmol·L^-1时N-DAMO菌的反硝化活性最大,CH4分压为49 kPa可基本满足N-DAMO菌对CH4的需求量,N-DAMO菌最适pH值为7.6左右,最适温度为35℃左右,N-DAMO菌能够适应一定含量的盐度;浅析了N-DAMO过程在海洋、淡水及其湿地等不同生境中的分布特点;在此基础上,探讨了Anammox与N-DAMO的耦合反应机理在污水处理脱氮工艺中的应用,该工艺能够节约大量物质能源、减少经济成本和提高脱氮效率,具有巨大的潜在应用前景。

Nitrite-type anaerobic methane oxidation(N-DAMO)refers to the microbial biochemical process in which methane is anaerobically oxidized to carbon dioxide using nitrite as an electron acceptor.This reaction is the key link of the coupled carbon-nitrogen cycle and the new content of the microbial carbon-nitrogen cycle.Its discovery has an important contribution to the global carbon-nitrogen cycle.Based on this,this paper summarized the biochemical reaction mechanism of N-DAMO process,and summarized the influencing factors of N-DAMO bacterial activity in enrichment and culture process:when the concentration of NO2^--N was 2.40 mmol·L^-1,the denitrification activity of N-DAMO bacteria was the highest;the partial pressure of CH4 was 49 KPa,which could basically meet the requirement of N-DAMO bacteria for CH4,the optimum pH value of N-DAMO bacteria was about 7.6,and the optimum temperature was about 35℃,the N-DAMO bacteria could adapt to a certain content of salinity.The distribution characteristics of N-DAMO process in different habitats such as ocean,freshwater and wetland were analyzed;On this basis,the application of coupling reaction mechanism between Anammox and N-DAMO in wastewater treatment denitrification process was discussed.This process can save a lot of material and energy,reduce economic costs and improve denitrification efficiency,and has great potential application prospects.