磺胺甲恶唑对新型后置缺氧反硝化工艺处理低C/N废水的影响

Effect of Sulfamethoxazole on the Treatment of Low C/N Wastewater by a New Post-Denitrification Process

磺胺甲恶唑(SMX)是废水内高频检出的新污染物,SMX的环境影响行为备受关注,然而SMX对新型后置反硝化工艺处理城镇低C/N废水的影响至今鲜有报道。本工作在中温条件下考察了SMX对新型后置缺氧反硝化工艺处理低C/N废水的影响,并通过分析SMX暴露条件下新工艺胞内和胞外聚合物的变化规律揭示SMX对新工艺的影响机制。结果表明低于0.5 mg/L SMX对新工艺内污染物去除影响不明显,而超过1.0 mg/L降低了新工艺脱氮除磷效率,4.0 mg/L SMX组别内,COD、总氮(TN)和磷酸盐(SOP)去除效率分别下降至71.3%~75.5%、59.6%~63.4%和71.3%~73.6%。机制分析表明高浓度SMX降低了胞内聚合物PHA的生物合成而刺激了糖原质代谢。SMX暴露浓度越高,PHA生物合成下降越显著,而糖原质代谢越强烈。研究结果为新型后置缺氧工艺处理含SMX废水提供了一定的数据支撑。

Sulfamethoxazole(SMX) is a new pollutant detected at high frequency in wastewater,and the environmental impact of SMX has attracted much attention.however,the effect of SMX on the treatment of urban wastewater with low C/N by a new post-denitrification process has not been reported so far.In this work,the effect of SMX on the treatment of low C/N wastewater by a new post-anoxic denitrification process was investigated at medium temperature,and the effect mechanism of SMX on the new process was revealed by analyzing the changes of intracellular and extracellular polymers in the new process under the condition of SMX exposure.The results showed that less than 0.5 mg/L SMX had no obvious effect on pollutant removal in the new process,while more than 1.0 mg/L reduced the nitrogen and phosphorus removal efficiency of the new process.In the 4.0 mg/L SMX group,the removal efficiency of COD,TN and TP decreased to 71.3%,59.6%,63.4% and 71.3%,respectively.Mechanism analysis showed that high concentration of SMX decreased the biosynthesis of intracellular polymer PHA and stimulated glycogen metabolism.The higher the exposure concentration of SMX,the more significant the decrease of PHA biosynthesis and the stronger the glycogen metabolism.The research results provide some data support for the treatment of SMX-containing wastewater by the new post-anoxic process.