摘要
市政管道碳排放是我国下水系统碳排放总量核查评估工作中的重要内容,相关研究甚少.明晰其产排机制与发生规模,探明管道内部因素对产排机制的影响,是实现准确评估的关键.聚焦CO_(2)产排机制,针对不同类型水力工况与管道底泥带来的影响,应用气相色谱与三维荧光光谱等方法,分析了在模拟高水位工况(C_A)、无水位工况(C_(B))及间歇高水位工况(C_C)条件下,市政污水管道沉积物(S_(sanitary))、雨水管道沉积物(S_(storm))及雨污混接管道沉积物(S_(mixed))的CO_(2)产排通量的差异,以及溶解性有机物(DOM)降解机制及其影响因素.结果表明:(1)在3类工况条件下,S_(mixed)在60 d内均呈现了最高的CO_(2)累计产排通量,分别为2.36×10^(5)、1.95×10^(5)、2.03×10^(5)mg/(m^(2)·d).(2)3类工况条件下,C_(B)中3种沉积物的CO_(2)产排受到抑制最为明显,最小CO_(2)日产排峰值均出现在C_(B)中,分别为3.20×10^(3)mg/(m^(2)·d)(S_(sanitary))、3.60×10^(3)mg/(m^(2)·d)(S_(storm))、4.35×10^(3)mg/(m^(2)·d)(S_(mixed)),表明外源碳是沉积物CO_(2)稳定产排的必要条件.(3)沉积物周期培养前期,在有上覆水时,C_A与C_C中显著存在色氨酸(A_(Ex)/λ_(Em)=275 nm/340 nm)类DOM降解,表明色氨酸类DOM降解是排水管道内上覆水存在时CO_(2)产排的主要贡献来源.本研究将为构建精细化管道碳排放核算评估体系提供数据支持,从而助力系统性碳排放削减方案.
Carbon emissions from municipal sewers are an important part of the total carbon emission verification and evaluation work in China′s sewage system,and also a blind spot problem that is faced at present.Clarifying its production and emission mechanism and occurrence scale,especially exploring the role of internal factors in the mechanism process,is a key prerequisite for achieving accurate evaluation.Focusing on the process of CO_(2)production and emission mechanism,in order to quantify the effects of different hydraulic conditions and sewer sediment,gas chromatography and three-dimensional fluorescence spectroscopy were used to analyze the differences in CO_(2)production and emission fluxes and degradation mechanism and influencing factors of dissolved organic matter(DOM)in sanitary sewer sediment(Ssanitary),storm sewer sediments(Sstorm)and illicit discharged storm sewer sediments(Smixed)under simulated high water level(CA),no water(CB)and intermittent high water level(CC)conditions.The research results indicate that:(1)Smixed has the highest cumulative CO_(2)emission flux within 60 days under three working conditions,which are 2.36×10^(5),1.95×10^(5),2.03×10^(5) mg/(m^(2)·d).(2)Among three conditions,the CO_(2)production and emission of three types of sediments in CB are most significantly inhibited,and the minimum peak daily CO_(2)emission fluxes are all in CB,which are 3.20×10^(3) mg/(m^(2)·d)(Ssanitary),3.60×10^(3) mg/(m^(2)·d)(Sstorm),4.35×10^(3) mg/(m^(2)·d)(Smixed),respectively,indicating that exogenous carbon is the necessary condition for the stable production and emission of carbon dioxide in sediments.(3)In the early stage of sediment cycle culture,when overlying water was present,the tryptophan(λEx/λEm=275 nm/340 nm)in DOM was significantly degraded in CA and CC,which was the main contributor to CO_(2)production and emission in drainage channels.This study provides data support for the construction of a refined sewer carbon emission accounting and evaluation system and helps systematic carbon emission reduction programs.Future work needs to further elucidate the key role of the microbiome,especially the functional flora,in the pipeline carbon emission mechanism.
作者
陈勋
陈浩
叶建锋
汪钟凝
朱弈
马长文
CHEN Xun;CHEN Hao;YE Jianfeng;WANG Zhongning;ZHU Yi;MA Changwen(School of Resources and Environmental Engineering,Shanghai Polytechnic University,Shanghai 201209,China;Shanghai Investigation,Design&Research Instiute Co.,Ltd.,Shanghai 200434,China;YANGTZE Eco-Environment Engineering Research Center,Three Gorges Corporation(Shanghai),Shanghai 200434,China;College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China;Shanghai Municipal Engineering Design Institute(Group)Co.,Ltd.,Shanghai 200092,China)
出处
《环境科学研究》
CAS
CSCD
北大核心
2023年第12期2344-2354,共11页
Research of Environmental Sciences
基金
上海科技创新行动计划项目(No.19DZ1204500)。
关键词
水力工况
沉积物
CO_(2)产排
DOM降解
hydraulic condition
sediment
CO_(2)production and emission
DOM degradation
