A^(2)O污水生物处理过程中DOM对N_(2)O生成的影响  

Effect of dissolved organic matter on N_(2)O generation in A^(2)O biological wastewater treatment process

作　　者：姜慧琪 于沛涵 胡振[1] 任延刚 郝泽育 韩珂 薛晨阳 王金鹤[4] JIANG Hui-qi;YU Pei-han;HU Zhen;REN Yan-gang;HAO Ze-yu;HAN Ke;XUE Chen-yang;WANG Jin-he(School of Environmental Science and Engineering,Shandong University,Qingdao 266237,China;University of Chinese Academy of Sciences,Beijing 100049,China;Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;School of Municipal and Environmental Engineering,Shandong Jianzhu University,Jinan 250101,China)

机构地区：[1]山东大学环境科学与工程学院,山东青岛266237 [2]中国科学院大学,北京100049 [3]中国科学院生态环境科学研究中心,北京100085 [4]山东建筑大学市政与环境工程学院,山东济南250101

出　　处：《中国环境科学》2025年第4期1869-1877,共9页China Environmental Science

基　　金：国家自然科学基金资助项目(52170043);国家重点研发计划课题(2021YFC3200602)。

摘　　要：采用三维荧光-平行因子法(3D EEMs-PARAFAC)解析了厌氧-缺氧-好氧(A^(2)O)污水生物处理过程中DOM特征,并对各工艺单元生成的N_(2)O进行了定量分析,之后运用机器学习模型对二者的变化关系进行了响应预测.结果表明,污水处理厂进水中DOM主要包含类色氨酸C1,类富里酸C2,类腐殖酸C3和类酪氨酸C4四种组分,并以C1和C4为主,且各组分含量沿污水处理流程逐渐降低,易生物降解的C1和C4的去除速率明显高于C2和C3.N_(2)O排放是直接碳排放的主要组成部分,其变化表现出明显的空间异质性,各处理单元N_(2)O生成总量由高到低依次为好氧池、辐流沉淀池、缺氧池、厌氧池、细格栅、钟式沉砂池.Shapley Additive ex Planation(SHAP)分析表明,C1和C2对N_(2)O生成影响较大,而C3和C4几乎没有影响,其中C1对N_(2)O的生成表现出促进作用,C2则不利于N_(2)O的生成.高通量测序结果表明,能够利用易生物降解有机物进行反硝化的Methylotenera和Terrimonas是污水处理厂内的优势菌属.本研究揭示了A^(2)O污水生物处理过程中N_(2)O生成对不同DOM组分的差异性响应,并为完善当前污水处理厂的碳排放核算方法并优化污水处理厂低碳运行工艺提供了理论支撑.In this study,the components of dissolved organic matter(DOM)during the anaerobic-anoxic-aerobic(A^(2)O)biological wastewater treatment process was analyzed by using fluorescence emission excitation matrix combined with parallel factor analysis(3D EEMs-PARAFAC),and the generation of nitrous oxide(N_(2)O)in each unit was also quantified.Additionally,machine learning model was employed to further predict the response relationship between DOM components and N_(2)O generation.Results showed that DOM in the influent of the wastewater treatment plants(WWTP)was primarily composed of four components,including tryptophan(C1),fulvic acid(C2),humic acid(C3),and tyrosine(C4),while C1 and C4 being the dominant components.The concentration of DOM decreased progressively throughout the treatment process,while the removal efficiency of readily biodegradable DOM(such as C1and C4)were significantly higher than that of C2 and C3.N_(2)O emission was the major component of direct carbon emissions and showed significant spatial heterogeneity.The N_(2)O emission amount of each unit ranked from high to low were observed in the following order:oxic tank,secondary sedimentation tank,anoxic tank,anaerobic tank,grille,and primary sedimentation tank.Shapley Additive exPlanation(SHAP)analysis revealed that C1 and C2 would significantly affect the N_(2)O generation process,while the effects of C3 and C4 were negligible.Specifically,C1would enhance N_(2)O generation,while C2 had an adverse effect.High-throughput sequencing results indicated that Methylotenera and Terrimonas,which could utilize readily biodegradable organic matter for denitrification,were the dominant bacterial genera in the sludge of WWTP.Overall,this study revealed disparate response between N_(2)O generation and different DOM components during the A^(2)O process,which would help to improve the current carbon emission accounting method of WWTPs and provide theoretical support for optimizing their low-carbon operation processes.

关 键 词：污水处理厂 氧化亚氮 溶解性有机物 厌氧-缺氧-好氧 碳排放 

分 类 号：X703[环境科学与工程—环境工程]