运行方式对低基质厌氧氨氧化系统脱氮及菌群结构的影响

为了考察运行方式对厌氧氨氧化系统脱氮性能及菌群结构的影响，建立一套厌氧移动床生物膜反应器，在(25±1) ℃恒温、低基质(TN≤60 mg·L⁻¹)条件下，分别以连续式和间歇式方式运行，采用高通量测序，基于直系同源蛋白簇基因(COGs)，对16S rRNA扩增子测序结果进行功能预测，来表征微生物菌群结构和微生物功能的变化。结果表明：系统总氮负荷为(227±13) mg·(L·d)⁻¹时，间歇式运行脱氮效率(90.6%)优于连续式运行效率(74.6%)，生物膜厌氧氨氧化细菌的相对丰度高于悬浮污泥；反应器由连续式变为间歇式运行后，主要功能菌属Ca. Brocadia丰度降低，同时，具有部分反硝化作用的Pseudomonas菌丰度出现明显升高。进一步分析可知，在适量的有机物条件下，间歇式运行能够获得更好的厌氧氨氧化与反硝化协同处理效果。本研究结果可为污水处理厂的实际运行提供参考。

Effect of operation modes on the nitrogen removal efficiency and microbial community structure of anammox process treating low substrate wastewater

In order to investigate the effect of operation modes on the nitrogen removal performance and microbial community structure of anaerobic ammonia oxidation system, an anaerobic moving bed biofilm reactor was established, which was operated in a continuous flow mode and a batch mode at constant temperature of (25±1) ℃ and low substrate of TN≤60 mg·L−1, respectively, used high-throughput sequencing, and based on cluster of orthologous groups of proteins (COGs) gene, 16S rRNA amplicon sequencing results were functionally predicted to characterize microbial flora structure and microbial function changes. The results showed that the nitrogen removal efficiency for the batch mode was 90.6%, which was higher than 74.6% for the continuous operation mode at the total nitrogen load of 227±13 mg·(L·d)−1. And the relative abundance of anammox bacteria in biofilm was higher than that in the suspended sludge. When the continuous mode of the reactor changed to batch mode, the abundance of main functional genus Ca. Brocadia decreased, while the abundance of bacteria with partial denitrification function increased significantly. Through further analysis, the batch mode can obtain better synergistic treatment effect of anammox and denitrification than continuous mode with proper amount of organic matter. The study provides a reference for the actual operation of wastewater treatment plant.