Higher N_(2)O production in sequencing batch reactors compared to continuous stirred tank reactors:effect of feast-famine cycles  

作　　者：Xinjie Yan Xunyu Shen Jipeng Wang Jinlong Zhuang Yu Wang Jinchi Yao Hong Liu Yongdi Liu James P.Shapleigh Wei Li 

机构地区：[1]National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery,East China University of Science and Technology,Shanghai 200237,China [2]State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process,School of Resources and Environmental Engineering,East China University of Science and Technology,Shanghai 200237,China [3]School of Environmental and Safety Engineering,Changzhou University,Changzhou 213164,China [4]Shanghai Huayi Group Co.Ltd.,Shanghai 201108,China [5]Shanghai Institute of Pollution Control and Ecological Security,Shanghai 200237,China [6]Department of Microbiology,Cornell University,Ithaca,NY 14850,USA

出　　处：《Frontiers of Environmental Science & Engineering》2023年第4期143-154,共12页环境科学与工程前沿（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(No.52170076);the Shanghai Rising-Star Program(China)(No.20QC1400500);the State Key Laboratory of Pollution Control and Resource Reuse(China)(No.PCRRF20024).

摘　　要：Nitrous oxide(N_(2)O)is a potent greenhouse gas that can be emitted during the biological treatment of wastewater.In this study,a comparison of the long-term performance characteristics and N_(2)O production of sequencing batch reactors(SBR)and continuous stirred tank reactors(CSTR)during nitrite-based denitrification was undertaken.It was found that both reactors had NO_(2)^(-)-N removal efficiencies over 99.9%,but the N_(2)O-N emissions from the SBR reached~2.3%of the removal nitrite-N load,while in the CSTR it never exceeded 0.1%.High frequency sampling during one operation cycle of the SBR demonstrated that the N_(2)O accumulation ratio was~0.1%during the feast period,increased to~1.9%in the first five hours of the famine period,and then gradually reached~2.3%at the end of famine.Batch experiments showed that limiting extracellular electron donor is required for N_(2)O accumulation in cells from the SBR-famine period and that cells from the CSTR do not accumulate N_(2)O when either nitrite or carbon is limiting.Another notable difference in the two reactor communities was the high level of accumulation of intracellular granules,most likely polyhydroxybutyrate(PHB),in cells during the feast period in the SBR.Metagenome assembly and binning found that one genome(PRO1),which is a Thauera,accounted for over half the metagenomic reads in both reactors.Neither shifts in gene regulation nor community composition explained the observed differences in reactor performance suggesting some post-transcriptional regulation obligatorily linked to antecedent conditions underly increased N_(2)O production in the SBR.

关 键 词：Denitrifying N_(2)O mitigation SBR CSTR Meta-omics PHB 

分 类 号：X703[环境科学与工程—环境工程]