黄铁矿基MFC-CW耦合系统反硝化动力学研究  

DENITRIFICATION KINETICS OF THE PYRITE-BASED MFC-CW COUPLING SYSTEM

作　　者：张倩倩[1,2] 鲁汭 安恒 卢欣怡 吴振斌 肖恩荣[1] ZHANG Qian-Qian;LU Rui;AN Heng;LU Xin-Yi;WU Zhen-Bin;XIAO En-Rong(Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,China;University of Chinese Academy of Sciences,Beijing 100049,China;School of Environmental Studies,China University of Geosciences,Wuhan 430074,China)

机构地区：[1]中国科学院水生生物研究所,武汉430072 [2]中国科学院大学,北京100049 [3]中国地质大学(武汉)环境学院,武汉430074

出　　处：《水生生物学报》2024年第7期1214-1224,共11页Acta Hydrobiologica Sinica

基　　金：国家自然科学基金(32371712和U20A2010)资助。

摘　　要：研究比较了黄铁矿基双阳极MFC-CW在不同碳氮比(0和2.5)及初始硝酸盐浓度(7、14和28 mg/L)条件下上阳极和下阳极的反硝化速率,以及对不同阶段硝酸盐还原反应动力学的模拟,从动力学角度揭示系统自养-异养协同反硝化机理。结果显示:不同碳氮比下系统两阳极硝酸盐还原效果差异不大,而亚硝酸盐累积、硫酸盐生成的差别较大,两阳极处微生物群落组成相似,优势菌属的相对丰度受C/N、阳极位置影响较大;两阳极处的硝酸盐还原动力学均属于一级反应,且C/N=0时反硝化速率常数(0.0087、0.0045和0.0188/h)均小于C/N=2.5(0.0151、0.0071和0.0798/h;以上阳极为例);MFC-CW系统的反硝化动力学更符合Monod-CSTR模型,且在停留时间较长时取得更好的拟合效果,随着停留时间的增加,C/N=0时系统的反硝速率增加,C/N=2.5时系统的反硝化速率在一定范围内波动[0.6662—0.7744 g/(m^(2)·d)]。实验结果可为黄铁矿基MFC-CW的实际工程应用提供理论指导。The hybrid system integrating a microbial fuel cell and constructed wetland(MFC-CW)utilizing pyrite substrates demonstrates the ability to enhance autotrophic denitrification.By leveraging reducible organic electrons,the system achieves a synergistic effect of autotrophic and heterotrophic denitrification in mixotrophism,particularly when treating wastewater with a low carbon to nitrogen ratio.In this study,we compared the denitrification rates in a pyritebased dual-anode MFC-CW under different carbon to nitrogen ratios(0 and 2.5)and initial nitrate concentrations(7,14,and 28 mg/L)at upper and lower anodes.Additionally,the study simulated the kinetics of the nitrate reduction reaction at different stages to elucidate the autotrophic-heterotrophic synergistic denitrification mechanism from a kinetic perspective.The results showed that:the Denitrification efficiency at the two anodes did not significantly differ under different carbon and nitrogen ratios,but variations were observed in nitrite accumulation and sulfate generation;Microbial community composition at the two anodes exhibited similarity,with the relative abundance of dominant genera significantly influenced by the C/N ratio and anode position.Nitrate reduction kinetics at both anodes represented a first-stage reaction,with the denitrification rate constant being smaller at C/N=2.5 compared to C/N=0;The denitrification kinetics of MFC-CW system aligned more with the Monod-CSTR model,with denitrification effect concentrated in the first 6h.In conclusion,the denitrification kinetics of the pyrite-based MFC-CW system,following the Monod-CSTR model,underscore its effectiveness,especially within the initial 6h.These results can provide theoretical guidance for the practical engineering application of pyrite-based MFC-CW.

关 键 词：黄铁矿 低碳氮比污水 微生物燃料电池耦合人工湿地 反硝化动力学 混养反硝化 

分 类 号：X703[环境科学与工程—环境工程]