二价铁对厌氧氨氧化的正向调控机理研究  

Study on Positive Regulation Mechanism of Iron Bivalent on Anammox

作　　者：张佳莉 王思宇[2] 李海波 郭建博 ZHANG Jiali;WANG Siyu;LI Haibo;GUO Jianbo(School of Environmental and Municipal Engineering,TCU,Tianjin 300384,China;Research Center for Integrated Management of Watershed Environmental Pollution,Chinese Research Academy of Environmental Sciences,Beijing 100012,China)

机构地区：[1]天津城建大学环境与市政工程学院,天津300384 [2]中国环境科学研究院流域水环境污染综合治理研究中心,北京100012

出　　处：《天津城建大学学报》2023年第4期262-267,共6页Journal of Tianjin Chengjian University

基　　金：天津市自然科学基金青年基金项目(19JCQNJC07600);天津市科技计划项目(20YDTPJC00480)。

摘　　要：通过探讨不同浓度Fe2+的电子穿梭作用对厌氧氨氧化体系氮转化速率的影响规律,解析了该过程厌氧氨氧化代谢产物的分泌特性,并利用电化学特征分析和电子传递活性实验,揭示了Fe2+电子穿梭效应强化厌氧氨氧化脱氮的作用机制.结果表明:2 mg/L的Fe2+使NH4+-N和NO2--N的转化量分别增加51.07%和34.13%,并促进胞外聚合物(EPS)的分泌,使蛋白(PN)和多糖(PS)分泌量从9.76、10.16 mg/gVSS提升至11.55、13.57 mg/g VSS,而PN/PS从0.96降至0.85,表明Fe2+有助于增强颗粒污泥的疏水性和稳定性.塔菲尔(Tafel)、循环伏安(CV)、脉冲循环伏安(DPV)曲线分析表明,Fe2+可增强反应体系的交换电流密度和电容,促进核黄素、细胞色素c结合物等电活性物质的分泌,以加速电子转移.此外,厌氧氨氧化体系电子传递活性(ETSA)提升了1.25倍,三磷酸腺苷(ATP)分泌量增加了2.35倍,表明Fe2+对微生物呼吸代谢和细胞活性具有正向调控作用.本研究阐明了Fe2+对厌氧氨氧化体系EPS分泌、电子传递及细胞代谢活性的影响机制,为工程中采用Fe2+强化厌氧氨氧化过程提供了理论支持.A study was used to explore the effect of Fe2+on nitrogen conversion rate,metabolite secretion characteristics,electrochemical characteristics and electron transport system activity in anaerobic ammonia oxidation(ANAMMOX).The results showed that the NH4+-N and NO2--N conversion was increased by 51.07%and 34.13%respectively,and the secretion of extracellular polymers was also promoted by 2 mg/L Fe2+.The content of protein(PN)and polysaccharide(PS)were increased from 9.76 and 10.16 mg/g VSS to 11.55 and 13.57 mg/gVSS respectively,while the PN/PS was decreased from 0.96 to 0.85,indicating the hydrophobicity and stability of granular sludge was enhanced by Fe2+.In addition,the curve analysis of Tafel,CV and DPV suggested that exchange current density and capacitance of the system were enhanced,and riboflavin and cytochrome C binding were secreted much more by Fe2+stimulated,thus accelerating electron transfer.Moreover,the electron transport system activity(ETSA)of anammox was increased by 1.25 times,and adenosine triphosphate(ATP)was secreted as much as 2.35 times,indicating positive regulation of Fe2+on microbial respiratory metabolism and cellular activity.This study clarified the influence mechanism of Fe2+on EPS secretion,electron transport and cell metabolic activity of anammox,and also provided theoretical support for the application of Fe2+for anammox strengthening in the engineering projects.

关 键 词：厌氧氨氧化 二价铁 代谢产物 电子传递 细胞活性 

分 类 号：X703[环境科学与工程—环境工程]