Based onMBRMicrobial Community Structure Analysis of shortcut nitrification initiation in different kinds of mud

Abstract

 For clear membrane bioreactor (MBR)Microbial Community structure changes before and after the short-cut Nitrification with different sludge inoculation.MBRNitrifying sludge (R1.),Anaerobic nitrification sludge (R2.)And1.:1.Mixed inoculation of anaerobic and Denitrifying sludge (R3.)Sludge source for achieving rapid short-cut nitrification.The results show that the combination of Intermittent Aeration and reduced hydraulic retention time (HRT),R1.R2.WithR3.Reactor time-consuming46 d,8 dAnd30 dThe shortcut nitrification was successfully launched,R2.Shortest startup cycle of Reactor.During the stable operation period,R1.R2.AndR3.The average nitrite accumulation rate was92%,93%And94%,R3.The reactor showed more stable short-cut Nitrification performance..Ace,Chao,ShannonAndSimpsonIndex results show that after stable operation,R1.AndR2.The microbial abundance and diversity of the reactor were significantly lower than that of the inoculated sludge,R3.The abundance of reactor species decreased slightly while the diversity level changed little..After the shortcut nitrification was successfully started,3.The main bacteria in the reactor were Proteus phyla (Proteobacteria)And bacteriocin (Bacteroidetes)And the abundance of the Main Nitrogen Removal Function bacteria is higher than that of the inoculated sludge..Beta-Proteus3.The dominant bacteria in the short-cut Nitrification system of each reactor accounted59. 6%,63. 6%And69. 3%.R1.R2.AndR3.Reactor in the advantage bacteria of are nitrosation single (Nitrosomonas)Of proportion respectively up12. 8%,Natural 20. 2%And19. 7%.ComparedR1Reactor,R2AndR3Reactor inoculation sludge in there is a certain proportion of nitrification bacteria more conducive to system short-range nitrification of implementation.