PN/A颗粒污泥-固相反硝化组合工艺的菌群功能解析

为解决部分亚硝化-厌氧氨氧化（PN/A）反应存在的硝酸盐残留问题，将PN/A颗粒污泥与固相反硝化（SPD）系统相耦合，用于高氨氮废水的连续处理。在逐级提高颗粒污泥自养脱氮效能的基础上，系统考察了石英砂、聚丁二酸丁二醇酯（PBS）和羟基丁酸戊酸共聚酯（PHBV）三种填料的SPD效能。结果表明，在高水力选择压下，PHBV的反硝化性能最佳，使PN/A-SPD组合工艺的总氮去除率超过了93%，远高于石英砂（83.6%）和PBS（85.8%）的水平。通过高通量测序与功能基因注释可知，固态碳源的溶出水平是影响生物膜菌群多样性的关键因素。其中，在PHBV表面占据主导的水解菌Clostridium-sensu-stricto-7与Comamonadaceae等反硝化菌形成了稳定的协作关系，在有效洗脱自养脱氮功能菌的同时，显著提升了菌群参与多元素循环的功能潜力。上述发现对于系统优化PN/A-SPD组合工艺，推动其工程化应用具有重要的指导意义。

Analysis of bacterial function in combined PN/A granular sludge and solid phase denitrification processes

For the control of residual nitrate in the effluent of partial nitritation and anaerobic ammonium oxidation (PN/A) system, a novel system was developed for the advanced nitrogen removal by coupling solid-phase denitrification (SPD) and PN/A granular sludge. On the basis of increasing the autotrophic denitrification efficiency of granular sludge step by step, the SPD of three fillers, quartz sand, polybutylene succinate (PBS) and hydroxybutyrate valeric acid copolyester (PHBV), was systematically investigated. The results indicated that the denitrification performance of PHBV was the best, the optimal total nitrogen (TN) removal efficiency exceed 93% in the PN/A-PHBV system, which was significantly higher than sand (83.6%) and PBS (85.8%) in high hydraulic pressure condition. According to the results of pyrosequencing analysis and the FAPROTAX function predicted, the dissolution level of solid carbon source is an important factor affecting the diversity of biofilm flora. Among them, the hydrolytic bacteria Clostridium-sensu-stricto-7, which was dominant on the surface of PHBV, formed a stable cooperative relationship with denitrifying bacteria such as Comamonadaceae, in addition to effectively eluting autotrophic denitrification functional bacteria, the functional potential of the flora to participate in multi-element cycling was significantly improved. The results of this study have significance in guiding for systematic optimization of the PN/A-SPD combination process and promoting its engineering application.