联合厌氧/微好氧的A/(O/A)_(n)强化好氧颗粒污泥脱氮除磷

Anaerobic/microaerobic combined with A/(O/A)_(n) to enhance nitrogen and phosphorus removal of aerobic granular sludge

设置3组规格相同的SBR反应器R1、R2和R3,分别采用A/O/A-A/O/A、A/O/A-A/O、A/(O/A)_(n)-A/O方式运行,以模拟废水为进水基质,接种实验室4℃长期饥饿储存的好氧颗粒污泥及絮状污泥(70%颗粒污泥+30%絮状污泥),在相同初始条件下,探讨了不同运行方式下颗粒污泥的活性恢复情况及短程硝化反硝化除磷性能.实验结果表明,联合厌氧/微好氧的A/(O/A)_(n)交替运行模式在实现颗粒污泥的活性恢复及污染物处理性能上表现出较大的优势,R3形成了平均粒径为802.98μm的密实颗粒,分泌的胞外聚合物(EPS)含量达到了94.52mg/gVSS,表明联合厌氧/微好氧的交替运行模式刺激了微生物分泌更多的EPS,颗粒结构更稳定.在稳定运行期间,R3的COD、TP、TN去除率分别达到了92.45%、93.72%和97.24%.系统内以亚硝酸盐为电子受体的反硝化聚磷菌所占比例达到了51.46%,实现了氨氧化菌(AOB)与反硝化聚磷菌(DPAOs)的同步富集,具有良好的污染物去除效果.

Three SBR reactors R1,R2 and R3 with the same specifications were set up,which were operated in A/O/A-A/O/A,A/O/A-A/O,and A/(O/A)_(n)-A/O modes respectively.Using synthetic wastewater as the influent substrate,the inoculated sludge,consisting of 70%aerobic granular sludge and 30%flocculent sludge,were obtained from the laboratory for long-term starvation at 4℃.Under the same initial conditions,the activity recovery and short-cut nitrification and denitrification phosphorus removal performance of granular sludge under different operation modes were discussed.The results showed that the combined anaerobic/micro-aerobic A/(O/A)_(n)alternating operation mode had great advantages in realizing the activity recovery of granular sludge and the performance of pollutant removal.The dense granules were formed with an average particle size of 802.98μm in R3,and the EPS content reached 94.52mg/gVSS,indicating that the alternating operation mode of combined anaerobic/microaerobic stimulated microorganisms to secrete more EPS,and the granule structure was more stable.During the stable operation period,the removal efficiency of COD,TP and TN of R3 reached 92.45%,93.72%and 97.24%respectively.Meanwhile,the proportion of denitrifying phosphorus accumulating organisms with nitrite as electron acceptor in the system reached 51.46%,which could realize the simultaneous enrichment of AOB and DPAOs,thereby exhibiting good pollutant removal effect.