温度和基质浓度对厌氧氨氧化工艺中N2O释放的影响  

Effects of Temperature and Substrate Concentration on NO Release of ANAMMOX Process

作　　者：王丝可 于恒 左剑恶 WANG Si-ke;YU Heng;ZUO Jian-e(State Key Joint Laboratory of Environmental Simulation and Pollution Control,School of Environment,Tsinghua University,,Beijing 100084,China)

机构地区：[1]清华大学环境学院,环境模拟与污染控制国家重点联合实验室,北京100084

出　　处：《环境科学》2020年第11期5082-5088,共7页Environmental Science

基　　金：国家自然科学基金项目(21677084)。

摘　　要：污水生物脱氮工艺中通常会释放温室气体N2O,厌氧氨氧化工艺作为新型生物脱氮工艺,其N2O的释放规律及机制值得深入研究.本文利用厌氧氨氧化序批试验,研究了不同温度和基质浓度对厌氧氨氧化工艺中N2O释放的影响,并探讨了N2O释放的微生物机制.结果表明,厌氧氨氧化工艺中进水基质浓度的增加会促进N2O释放,在35℃条件下,当进水亚硝氮从40 mg·L^-1增加至60 mg·L^-1和120 mg·L^-1时,N2O最高积累浓度从0.5 mg·L^-1增加至1.5 mg·L^-1和2.4 mg·L^-1,分别占总氮去除量的0.85%、1.43%和1.11%.温度降低对厌氧氨氧化活性抑制作用明显,15℃下的比厌氧氨氧化活性仅为30℃时的6%.温度降低导致厌氧氨氧化工艺中N2O的释放减少,温度降低时反硝化速率的降低是导致N2O产生速率降低、N2O积累减少的主要原因.厌氧氨氧化工艺微生物群落中存在丰富的异养反硝化菌,工艺中N2O积累主要是反硝化菌产生和消耗N2O的结果.The greenhouse gas N2O is released during the biological nitrogen removal process.ANAMMOX(anaerobic ammonium oxidation)is regarded as a promising nitrogen removal process for treating municipal wastewater,and the N2O emission patterns and mechanisms need further investigation.In this study,batch tests were performed to study the release of N2O at different temperatures and substrate concentrations,and the microbial mechanisms of N2O emission were discussed.The results showed that the increase of the influent substrate concentration of the ANAMMOX process promoted the release of N2O.At 35℃,when the influent nitrite increased from 40 mg·L^-1 to 60 mg·L^-1,120 mg·L^-1,the maximum accumulated concentration of N2O increased from 0.5 mg·L^-1 to 1.5 mg·L^-1 and 2.4 mg·L^-1,accounting for 0.85%,1.43%,and 1.11%of the total nitrogen removal,respectively.Lowering temperature had an obvious inhibitory effect on ANAMMOX activity.The specific ANAMMOX activity at 15℃was only 6%of that at 30℃.Furthermore,the intracellular ATP concentration was reduced.At 15℃,the intracellular ATP concentration was 4%of that at 30℃.The decrease in temperature led to a decrease in the release of N2O in the ANAMMOX process.When the temperature decreased,the denitrification rate would decrease,leading to a lower N2O production rate and lower N2O accumulation.16 S rRNA amplicon sequencing showed that ANAMMOX bacteria Candidatus Brocadia and Ca.Jettenia were enriched,accounting for 6.9%-13.8%and 1.4%-2.6%of microbial community,respectively.Abundant heterotrophic bacteria were also found in the microbial community.The accumulation of N2O in the ANAMMOX process was mainly attributed to denitrifying bacteria producing and consuming N2O.This study provides support for controlling N2O emission during the ANAMMOX process for treating municipal wastewater.

关 键 词：厌氧氨氧化(ANAMMOX) 氧化亚氮(N2O) 温度 基质浓度 微生物群落 

分 类 号：X703[环境科学与工程—环境工程]