A^(2)/O与倒置A^(2)/O工艺低温条件下的氨氮去除能力解析  

Ammonia Nitrogen Removal Performance with Parallel Operation of Conventional and Inverted A^(2)/O Sewage Treatment Processes in Winter

作　　者：李金成 郭雅妮[1] 齐嵘[2] 杨敏[2] LI Jin-cheng;GUO Ya-ni;QI Rong;YANG Min(School of Environmental and Chemical Engineering,Xi'an Polytechnic University,Xi'an 710048,China;State Key Laboratory of Environmental Aquatic Chemistry,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China)

机构地区：[1]西安工程大学环境与化学工程学院,西安710048 [2]中国科学院生态环境研究中心环境水质学国家重点实验室,北京100085

出　　处：《环境科学》2021年第8期3866-3874,共9页Environmental Science

基　　金：国家重点研发计划项目(2016YFC0400804)。

摘　　要：对相同进水、平行运行的A^(2)/O与倒置A^(2)/O工艺的冬季氨氮(NH4+-N)去除能力进行了全面解析.在运行水温为14℃时,倒置A^(2)/O工艺表现出更低的NH4+-N容积去除负荷[0.13 kg·(m^(3)·d)^(-1)和0.29 kg·(m^(3)·d)^(-1)]和氨氧化速率(AOR)[0.07 kg·(kg·d)^(-1)和0.11 kg·(kg·d)^(-1)],而26℃时两个工艺则相差无几.两个平行工艺中的氨氧化菌(AOB)种群定量结果几乎始终相等(倒置A^(2)/O工艺为3.2%±0.24%,A^(2)/O工艺为3.4%±0.31%).克隆文库分析的结果表明,造成低温时倒置A^(2)/O工艺中具有较低氨氮去除能力的原因是其AOB优势种属为AOR较慢的慢生型(K-生长策略)亚硝化螺菌属(Nitrosospira),而在A^(2)/O工艺中则为AOR较快的快生型(r-生长策略)亚硝化单胞菌属(Nitrosomonas);而在26℃环境下两个工艺中的优势种属则均为Nitrosomonas.结合对污染物沿程去除过程的全面分析,发现尽管温度是决定AOB优势种属演替的首要原因,但由于倒置A^(2)/O的工艺结构变化造成其好氧单元具有较高的COD负荷和高NH_(4)^(+)-N浓度等不利于AOB生长的因素,决定了其可以在常规城市污水的条件下出现K-生长策略型的优势AOB种属.因此倒置A^(2)/O针对异养菌(聚磷菌与反硝化菌)的工艺构造变化却通过COD负荷等间接影响到自养型氨氧化菌的种群分布与演替,并最终造成工艺在低温条件下硝化能力的减弱.Ammonia nitrogen (NH4+-N) removal capacities of the A^(2)/O and inverted A^(2)/O processes were analyzed with the same inlet and parallel operation during winter.When the operating water temperature was 14℃,the inverted A^(2)/O process exhibited lower NH4+-N removal from the volumetric load[0.13 kg·(m^(3)·d)^(-1)vs.0.29 kg·(m^(3)·d)^(-1)]and a lower ammonia oxidation rate (AOR)[0.07 kg·(kg·d)^(-1)vs.0.11 kg·(kg·d)^(-1)]than the A^(2)/O process,whereas the two processes exhibited similar performance at26℃.The quantitative results for the ammonia oxidizing bacteria (AOB) population were almost the same in the two parallel processes(3.2%±0.24% for the inverted A^(2)/O process and 3.4%±0.31%for the A^(2)/O process).Clone library analysis showed that at low temperatures,the inverted A^(2)/O process had a lower capacity for ammonia nitrogen removal than A^(2)/O process.This is because the particular AOB species[spirillum (Nitrosospira)]facilitated the slower AOR type (K-growth strategy) of nitrosation in the inverted A^(2)/O process,whereas in the A^(2)/O process,the faster AOR type (r-growth strategy) of nitrosation was facilitated by bacterium(Nitrosomonas).At 26℃,the dominant species in the two processes were Nitrosomonas.Through comprehensive analysis of the pollutants during the removal process,we found that although temperature is the leading cause of AOB advantage in species succession,the changes in the inverted A^(2)/O process structure,caused by the aerobic unit,resulted in high COD load and high NH_(4)^(+)-N concentration,which were unfavorable for the growth of AOB.This shows that under conventional sewage conditions,the K-growth strategy is advantageous for the AOB species.Therefore,the structure of the inverted A^(2)/O process for heterotrophic bacteria(phosphorus accumulating bacteria and denitrifying bacteria) indirectly affects the population distribution and succession of autotrophic ammonia-oxidizing bacteria,through COD load and other factors,thereby leading to weakened nitrification

关 键 词：倒置A^(2)/O 氨氧化细菌 克隆文库 COD负荷 低温 

分 类 号：X703[环境科学与工程—环境工程]