连续低氧曝气与间歇曝气主流Anammox运行效能及微生物特性对比

Comparison of operating performance and microbial characteristics achieving mainstream Anammox between continuous low-oxygen aeration and intermittent aeration modes

分别在连续低氧曝气和间歇曝气两种条件下比较了主流厌氧氨氧化(Anammox)处理模拟城市污水的运行效果.结果表明,间歇曝气方式实现主流Anammox时间更短,仅需24d.间歇曝气下氨氮去除率(ARE)为(96.0±1.0)%、总氮去除率(TNRE)为(80.2±2.0)%,相较之下,脱氮效率更稳定且氮去除负荷更高.间歇曝气使好氧和厌氧氨氧化活性均处于更高水平,并促进胞外聚合物(EPS)分泌、蛋白质(PN)含量增加及蛋白质/多糖(PN/PS)升高,能够形成更加致密且红色的厌氧氨氧化生物膜结构;三维荧光光谱发现间歇曝气时溶解性EPS(S-EPS)的峰A的荧光强度显著增加.高通量测序证实曝气方式不同导致了微生物群落组成及功能基因数量存在显著差异.间歇曝气改善好氧氨氧化菌的种群结构并增加相对数量.有助于Anammox菌属(Candidatus Brocadia、Candidatus Kuenenia)富集.基因注释结果表明间歇曝气条件下可能存在部分硝化/部分反硝化+厌氧氨氧化协同脱氮途径.

Operating performance of mainstream anaerobic ammonia oxidation(Anammox) for treating simulated municipal wastewater was compared respectively under two modes of continuous low-oxygen aeration and intermittent aeration. Intermittent aeration achieved mainstream Anammox in a shorter period with only 24d. The ammonia removal efficiency(ARE) was(96.0±1.0)%and the total nitrogen removal efficiency(TNRE) was(80.2±2.0)% under intermittent aeration. Compared with continuous aeration,nitrogen removal efficiency was more stable and nitrogen removal loading rate was higher. Intermittent aeration elevated both aerobic and anaerobic anammox activities, promoting extracellular polymeric substance(EPS) secretion, increasing protein(PN)content and protein/polysaccharide(PN/PS), which could form a more dense and red anammox biofilm structure. Three-dimensional fluorescence spectra found that the fluorescence intensity of peak A of soluble EPS(S-EPS) increased significantly during intermittent aeration. High-throughput sequencing confirmed that different aeration ways caused significant differences in microbial community composition and quantity of functional genes. Intermittent aeration improved the population structure and increased the relative abundance of aerobic ammonia oxidizers and contributed to the enrichment of Anammox bacteria(Candidatus Brocadia,Candidatus Kuenenia). The gene annotation results indicated synergistic nitrogen removal pathway of partial nitrification/partial denitrification +anammox existed in intermittent aeration condition.