摘要 为了确定反硝化聚糖菌(DGAOs)的脱氮性能及N2O释放特性,采用序批式生物反应器,分别以乙酸钠和葡萄糖为碳源(反应器分别记作SBRAc和SBRGl),考察其脱氮过程中的碳源变化以及N2O释放特性。结果表明,SBRAc和SBRGl的总氮去除率分别为(80.2±2.8)%和(63.4±3.5)%,N2O产率分别为(7.16±1.43)%和(13.35±2.46)%。以乙酸钠为碳源时,聚糖菌厌氧阶段吸收的有机物主要以胞内聚-β-羟基烷酸(PHA)形式储存;以葡萄糖为碳源时,部分有机物用于胞内糖原(Gly)的积累,PHA合成量减少。聚糖菌内源反硝化过程中,依次利用胞内PHA和Gly作为内碳源,且PHA提供电子的速率远大于Gly,导致SBRGl内NO2-大量积累、N2O释放量增加。NO2-对氧化亚氮还原酶活性的抑制效应是导致聚糖菌内源反硝化过程释放N2O的主要因素。与葡萄糖相比,乙酸钠更易被反硝化聚糖菌吸收为易利用的内碳源PHA,并降低反硝化过程中N2O的释放量。 In order to investigate the denitrification efficiency and N2O emission characteristic of denitrifying glycogen accumulating organisms(DGAOs),variation of the endogenous polymer and N2O emission characteristic during endogenous denitrification process were explored in two separated sequencing batch reactors(SBRAc and SBRGl)using sodium acetate and glucose as carbon sources respectively.The total nitrogen removal efficiencies of SBRAc and SBRGl were(80.2±2.8)%and(63.4±3.5)%,and the N2O yields were(7.16±1.43)%and(13.35±2.46)%,respectively.When sodium acetate was used as carbon source,organics absorbed by DGAOs in anaerobic stage was stored in the form of endogenous polyhydroxyalkanoate(PHA).When glucose was used as carbon source,part of the organics was used for intracellular glycogen(Gly)accumulation,and PHA synthesis decreased.In the endogenous denitrification process of DGAOs,PHA and Gly were successively used as endogenous carbon sources,and the rate of electron supply by PHA was much higher than that of Gly,leading to accumulation of a large amount of NO2-and increase of N2O emission in SBRGl.The inhibitory effect of NO2-on activity of nitrous oxide reductase was the main factor leading to N2O emission during the endogenous denitrification of DGAOs.Compared with glucose,sodium acetate was more easily absorbed by DGAOs as an easily used endogenous carbon source PHA,and the emission of N2O during denitrification was reduced.
机构地区 烟台职业学院建筑工程系 北京工业大学城镇污水深度处理与资源化利用技术国家工程实验室
出处 《中国给水排水》 CAS CSCD 北大核心 2021年第5期17-25,共9页 China Water & Wastewater
基金 国家自然科学基金:资助项目(51508008) 烟职博士科研启动基金:资助项目(2018002) 烟台职业学院2021年度横向课题。
关键词 反硝化聚糖菌 内源反硝化 N2O释放 聚-β-羟基烷酸 胞内糖原 denitrifying glycogen accumulating organisms endogenous denitrification N2O emission polyhydroxyalkanoate glycogen
分类号 TU992 [建筑科学—市政工程]
