氟苯尼考降低生物除磷性能的影响行为及机制解析

Behavior and mechanism analysis of florfenicol Influence on biological phosphorus removal performance

为探究新兴污染物氟苯尼考(FF)对强化生物除磷(EBPR)的影响及作用机制,构建了序批式反应器,通过不同质量浓度的FF短期和长期暴露,分析了生物除磷效率的变化规律,解析了FF和胞外聚合物的作用机制,明确了EBPR内微生物群落结构对FF的响应特征.研究发现,FF对EBPR性能的影响具有浓度依赖性,即0.1 mg·L^(-1)的FF对EBPR的性能没有明显影响,而2.0 mg·L^(-1)的FF降低了除磷效率.机制研究表明,2.0 mg·L^(-1) FF长期暴露对厌氧阶段磷酸盐的释放没有影响,但降低好氧阶段磷酸盐的过量吸收.三维荧光分析表明,2.0 mg·L^(-1) FF对活性污泥的胞外聚合物的结构和成分有明显影响.微生物群落结构分析表明,与空白组相比,2.0 mg·L^(-1)的FF提高了Candidatus Competibacter、Tetrasphaera和Terrimonas的相对丰度,分别至19.00%、5.28%和16.28%,但显著地降低了Chinophagaceae的相对丰度.本结果为EBPR工艺处理含FF的废水提供了一定的参考依据.

The influencing mechanism of florfenicol(FF),an emerging contaminant,on enhanced biological phosphorus removal(EBPR)using sequencing batch reactors Through short-term and long-term exposure to different doses of FF,the change of BPR efficiency was analyzed,the interaction mechanism of FF and extracellular polymeric substances(EPS)were analyzed,and the response of microbial community structure in EBPR to FF were defined.It is found that the effect of FF on the performance of EBPR was dose-dependent,and 0.1 mg·L^(-1) FF had no significant effect on the performance of EBPR,while 2.0 mg·L^(-1) FF reduced phosphorus removal efficiency.The mechanism study results showed that long-term exposure of 2.0 mg·L^(-1) FF had no effect on phosphate release in the anaerobic phase,but decreased the excess phosphate absorption in the aerobic phase.Threedimensional fluorescence analysis result showed that 2.0 mg·L^(-1) FF had a significant effect on the structure and composition of EPS from activated sludge.Microbial community structure analysis result showed that 2.0 mg·L^(-1) of FF increased Candidatus Competibacter compared with the blank group.The relative abundances of Candidatus Competibacter and Terrimonas reached 19.00%and 16.28%respectively,but decreased the relative abundance of Chinophagaceae.The results provide a reference for the treatment of FF-containing wastewater by EBPR process.