DO/NH_4^+-N实现短程硝化过程中生物膜特性  

Characteristics of Biofilm During the Transition Process of Complete Nitrification and Partial Nitrification

作　　者：赵青[1] 卞伟[1] 李军[1] 王文啸 孙艺齐 梁东博 张舒燕 

机构地区：[1]北京工业大学建筑工程学院,北京100124 [2]神华集团中国节能减排有限公司,北京100011

出　　处：《环境科学》2018年第3期1278-1285,共8页Environmental Science

基　　金：国家水体污染控制与治理科技重大专项(2015ZX07202-013)

摘　　要：实验探究了短程硝化实现过程中生物膜特性的变化情况.采用比值控制(DO/NH+4-N)实现短程硝化,分别取亚硝酸盐积累率为10.27%、52.12%和93.54%时生物膜样品,利用荧光原位杂交(FISH)和激光共聚焦显微镜(CLSM)联用技术观察总菌、氨氧化菌(AOB)和亚硝酸盐氧化菌(NOB)数量和空间结构的变化,通过三维激发发射矩阵(EEM)观察胞外聚合物分泌和成分变化情况.比值控制成功富集AOB,并可在NOB未洗脱完全的情况下实现短程硝化.异养菌和硝化菌共存于生物膜内上,异养细菌在外层,硝化菌分布在生物膜表面6~25μm.短程硝化实现的过程中,AOB/NOB值逐步增长,稳定运行时期比值高达15.56.反应器运行过程中,EPS和微生物菌群变化息息相关.微生物活性下降,EPS分泌减少;短程硝化稳定运行时期,NOB等不耐高亚硝酸的菌群衰亡,芳香性蛋白质荧光强度降低.但三维荧光光谱显示,短程硝化实现过程中EPS化学成分变化不明显.The objective of the study was to investigate the change of biofilm characteristics when implementing the procedure of partial nitrification. A ratio control strategy（DO/NH4^＋-N） was taken to achieve partial nitrification,and biofilm samples were obtained at10. 27%,52. 12%,and 93. 54% of the nitrite accumulation rate. The amount and spatial distribution of total bacteria,ammonia oxidizing bacteria（AOB）,and nitrite oxidative bacteria（NOB） were observed by fluorescence in situ hybridization（FISH） and confocal laser scanning microscope（CLSM） through a three-dimensional excitation emission matrix（EEM） to observe the secretion and composition changes of extracellular polymer substances. Ratio control successfully enriched AOB and achieved partial nitrification under conditions when NOB was not completely washed. Heterotrophic bacteria and nitrifying bacteria coexist in the biofilm. The heterotrophic bacteria were in the outer layer,but nitrifying bacteria were distributed in the biofilm surface at 6-25 μm. During the process of short-range nitrification,the AOB/NOB value gradually increased,and the stable operation period was as high as 15. 56.During the operation of the reactor,EPS and microbial flora changes are closely related. When microbial activity decreased,EPS secretion decreased. During the stable operation period of partial nitrification,NOB and other bacteria that are non-resistant to high nitrite nitrous acid declined,and the fluorescence intensity of aromatic protein-like bacteria decreased. However,the three-dimensional fluorescence spectra showed that the chemical composition of EPS was not obvious during the process of partial nitrification.

关 键 词：短程硝化 生物膜 硝化细菌 胞外聚合物 

分 类 号：X703.5[环境科学与工程—环境工程]