复合填料ANAMMOX系统脱氮效能及微生物群落研究

为实现厌氧氨氧化菌(AnAOB)的高效富集，于第26天和第95天在反应器内分别添加活性炭填料和组合填料，构建复合填料ANAMMOX (anaerobic ammonium oxidation，厌氧氨氧化)系统. 通过测定进出水NH₄+-N、NO₂?-N和NO₃?-N浓度变化，考察在不同时期添加填料对反应器脱氮效能的影响，并运用16S rRNA高通量测序技术考察污泥的微生物多样性和群落结构变化情况. 结果表明:①经过160 d的运行，成功构建了具有良好抗冲击负荷能力的复合填料ANAMMOX系统，且其稳定运行期间，TN容积负荷(NLR)和TN去除负荷(NRR)分别可达0.97和0.83 kg/(m3·d)，化学计量比接近理论值1∶1.32∶0.26. ②复合填料ANAMMOX系统促进了AnAOB的富集，污泥颜色由初始的黑色逐渐转变为红褐色，并出现ANAMMOX颗粒污泥，复合填料表面有大量AnAOB聚集形成了红色生物膜. ③第160天时，AnAOB在系统中处于主导地位. 门水平分析发现，浮霉菌门的相对丰度由0.77%提至33.17%，绿弯菌门的相对丰度从9.17%提至22.65%，其他菌门的相对丰度降低；属水平分析发现，ANAMMOX菌种Candidatus jettenia和Candidatus brocadia的相对丰度分别为30.56%和1.93%. 研究显示，复合填料ANAMMOX系统可以维持反应器稳定的脱氮效率，同时能实现AnAOB的高效富集. 

Nitrogen Removal Efficiency and Microbial Community of an ANAMMOX System with Combined Fillers

An combined filler ANAMMOX (anaerobic ammonium oxidation) system was constructed to achieve the high efficient enrichment of anaerobic ammonium oxidation bacteria (AnAOB) by adding activated carbon filler on the 26th day and composite filler on the 95th day. The nitrogen removal efficiency of the ANAMMOX system at different operating stages was investigated, and 16S rRNA high-throughput sequencing was used to analyze the changes of microbial diversity and community structure of the sludge. The results showed that: (1) After 160 days′ operation, the composite filler ANAMMOX system was constructed successfully showed good shock load resistance. During stable operation stages, total nitrogen volumetric load (NLR) and total nitrogen removal load (NRR) of the system reached 0.97 and 0.83 kg/(m3·d), respectively. The stoichiometric ratio was close to the theoretical value of 1∶1.32∶0.26. (2) The composite filler ANAMMOX system promoted enrichment of AnAOB, and finally ANAMMOX granular sludge appeared with a large amount of AnAOB gathered on the surface of the composite filler to form a red biofilm. (3) On the 160th day, the system was dominated by AnAOB. Phylum level analysis revealed that the relative abundance of the Planctomycetotes increased from 0.77% to 33.17%, the relative abundance of Chloroflexi increased from 9.17% to 22.65%, while the relative abundance of other phylum decreased. In addition, the relative abundance of Candidatus jettenia and Candidatus brocadia on genus level increased to 30.56% and 1.93%, respectively. The study indicated that the combined filler ANAMMOX system is beneficial to achieve high-efficient enrichment of AnAOB and maintain the stable nitrogen removal efficiency.