羊粪生物炭强化CRI系统厌氧氨氧化脱氮性能研究

Study on the Mechanism of Sheep Manure Biochar Enhanceing the Nitrogen Removal Performance of Anammox of CRI System

为提高人工快渗(CRI)系统的脱氮效率,制备羊粪生物炭(SMB)并考察了其对CRI系统厌氧氨氧化启动过程中氮转化效率的影响,结合生物炭表征、生物膜特性和菌群结构变化解析了SMB强化厌氧氨氧化脱氮性能的机理。结果表明,在CRI系统滤料层添加质量分数为20%的SMB,可在运行43 d后成功启动厌氧氨氧化,总氮(TN)去除率达到94.6%,其启动时间比未添加SMB时缩短了25.9%,脱氮效率比未添加SMB时提高了8.3个百分点。SMB的添加可为CRI系统内微生物提供更优质的载体条件,刺激胞外聚合物的分泌,形成更稳定的生物膜结构,比厌氧氨氧化活性比未添加SMB时提高了20.3%。添加SMB后,CRI系统内厌氧氨氧化菌属Candidatus_Brocadia的相对丰度增长到26.25%,同时Denitratisoma、Thauera、Flavobacterium等反硝化菌群协同共存于体系内,促使系统在更短的启动时间内获得更高的TN去除效果,强化其厌氧氨氧化脱氮性能。

In order to improve the nitrogen removal efficiency of constructed rapid infiltration(CRI)system,sheep manure biochar(SMB)was prepared and its effect on the nitrogen conversion efficiency during the anaerobic ammonia oxidation start-up of CRI system was investigated.Combined with biochar characterization,biofilm characteristics and microbial structure changes,the mechanism of SMB enhancing the Nitrogen removal performance of anammox was analyzed.The results show that adding SMB with a mass fraction of 20%in the filter layer of CRI system can successfully start anammox after 43 days of operation,and the total nitrogen(TN)removal rate reaches 94.6%.The start-up time is shortened by 25.9%and the nitrogen removal efficiency is increased by 8.3 percentage points compared with that without SMB.The addition of SMB can provide better carrier conditions for microorganisms in the CRI system,stimulate the secretion of extracellular polymers,and form a more stable biofilm structure.The anaerobic ammox activity is increased by 20.3%compared with that without SMB.After adding SMB,the relative abundance of anammox bacteria Candidatus_Brocadia in the CRI system increases to 26.25%,and denitrifying bacteria such as Denitratisoma,Thauera and Flavobacterium coexist collaboratively in the system.It promotes the system to obtain higher TN removal effect in a shorter start-up time,and enhances its anaerobic ammonia oxidation nitrogen removal performance.