磁场强化曝气生物滤池处理高浓度氨氮废水的研究

Treatment of high concentration ammonia wastewater by using aeration biological filter enhanced by magnetic field

本研究采用普通陶粒、普通陶粒外加静态磁场(50 mT)和磁性陶粒(2.5 mT和5 mT)曝气生物滤池处理高浓度氨氮废水,对比研究了不同类型和强度的磁场强化下曝气生物滤池的硝化反硝化效果,并通过分子生物学手段系统分析了磁场强化硝化反硝化的微生物学机理.结果表明,随着氨氮浓度增加,磁场强化下曝气生物滤池硝化反硝化效果显著高于普通陶粒曝气生物滤池.当氨氮浓度提高到400 mg∙L^(-1)时,磁场强化曝气生物滤池(磁性陶粒和外加静态磁场)的氨氮去除率大于97%,高于普通陶粒曝气生物滤池的氨氮去除率(88%);磁场强度为2.5 mT的磁性陶粒曝气生物滤池的总氮去除率达到67%,显著高于其他3个曝气生物滤池(p<0.05)(分别为55%、54%和55%).分子生物学检测结果表明,2.5 mT磁场强度的磁性陶粒上生物膜的硝化反硝化酶活性和功能基因丰度大幅提高,硝化反硝化细菌的丰度及多样性显著增加.

In this study,four reactors filled with normal ceramsite packing materials,with/without 50 mT static magnetic field,and magnetic ceramsite(2.5 mT and 5 mT,respectively)were used to treat high⁃concentration ammonia nitrogen wastewater.The performance of different type and strength of magnetic field on the nitrification and denitrification performance were investigated.Molecular biology methods were used to clarify the microbial mechanism of magnetic field enhancing the nitrification and denitrification processes.The results showed that with the increase of ammonium concentration,the nitrification and denitrification performance of the reactors enhanced by magnetic field were significantly higher than that of reactor filled with normal ceramsite.When the ammonium concentration increased to 400 mg·L^(-1),the ammonium removals of the reactors enhanced by magnetic field were greater than 97%,which was higher than that of the reactor filled with ordinary ceramsite(88%).The total nitrogen removal of the reactor filled with magnetic ceramsite filler of 2.5 mT reached 67%,which was significantly higher than those of the other three reactors(55%,54% and 55%)(p<0.05).The results of molecular biological analysis showed that the enzyme activities,the abundance of functional genes,and the abundance and diversity of bacteria for nitrification and denitrification greatly increased in the biofilm on the magnetic ceramsite under 2.5 mT.