摘要
聚乳酸(PLA)是一种发展潜力巨大的反硝化固体碳源。为探究不同分子量PLA反硝化脱氮路径及机制,以不同分子量PLA为固体碳源研究了PLA的静态释碳性能和反硝化脱氮效果,考察了反硝化出水溶解性有机质(DOM)组分和微生物群落结构。结果表明:PLA释碳稳定,在清水和脱氮反应器中出水COD均能稳定在20 mg·L^(-1);PLA分子量越低,脱氮效果越好,5000 g·mol^(-1)分子量PLA的NO_(3)^(-)-N去除率和反硝化速率达到100%和1.29 mg·L^(-1)·h^(-1)。PLA脱氮路径有2条:一是反硝化功能菌群利用水解微生物分解PLA释放的小分子碳源作为电子供体进行异养反硝化作用;一是微生物利用溶解性微生物代谢产物等有机物进行反硝化脱氮。该研究结果可为PLA固体碳源在反硝化脱氮工艺中的高效应用提供参考。
Polylactic acid(PLA)is a kind of denitrification solid carbon source with great potential.In order to explore the denitrification pathway and mechanism of PLA with different molecular weights,the static carbon release performance and denitrification efficiency of PLA with different molecular weights were studied,and the effluent of dissolved organic matter(DOM)components and the microbial community structure were analyzed.The results showed that PLA carbon release performance was stable,and the effluent COD concentration in both deionized water and nitrogen removal reactors could be stabilized at 20 mg·L^(−1).The lower the molecular weight of PLA was,the better the nitrogen removal efficiency was.The NO_(3)^(−)-N removal rate and denitrification rate of 5000 g·mol^(−1)molecular weight PLA reached 100%and 1.29 mg·L^(−1)·h^(−1).There were two pathway for PLA denitrification,one was that denitrifying bacteria used the small molecule weight carbon source released by hydrolyzed microorganisms PLA as electron donor for heterotrophic denitrification,the other one was that microorganisms used organic matter such as dissolved microbial metabolites for denitrification.The research results can provide a theoretical basis for the efficient application of PLA as solid carbon source in denitrification process.
作者
张雨薇
阿蓉
黎佳茜
李杰
刘雪瑜
魏东洋
ZHANG Yuwei;A Rong;LI Jiaxi;LI Jie;LIU Xueyu;WEI Dongyang(Department of Urban Water Environmental Research,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;Department of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Department of Chemistry and Chemical Engineering,Northwest Normal University,Lanzhou 730070,China;Gansu Membrane Science and Technology Research Institute Co,Ltd,Lanzhou 730020,China;Environmental Development Center,Ministry of Ecology and Environment,Beijing 100029,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2023年第5期1599-1611,共13页
Chinese Journal of Environmental Engineering
基金
深圳市科技计划协同创新专项-承接国家重大科技项目(CJGJZD2020061710260200)
国家重点研发计划项目(2021YFC3201505-02)。
关键词
固体碳源
聚乳酸
异养反硝化
三维荧光光谱
微生物群落结构
solid carbon source
polylactic acid
heterotrophic denitrification
three-dimensional fluorescence spectroscopy
microbial community structure
