活性炭强化好氧颗粒污泥运行效能的探究

Study on Activated Carbon to Enhance the Operation Efficiency of Aerobic Granular Sludge

针对好氧颗粒污泥(AGS)颗粒化进程缓慢及低碳/氮(C/N)废水处理效率低的特性,在中温条件下开展了污泥源颗粒活性炭(GAC)强化AGS处理低C/N废水的研究,探究了GAC对AGS出水水质特征、污泥颗粒化进程及微生物群落特征的影响,揭示了GAC强化AGS处理低C/N废水的作用机制。结果表明,GAC能强化AGS处理低C/N废水的性能,当GAC含量20 mg/L时,COD、NH_(4)^(+)-N、TP的去除效率分别高达92.6%~98.5%、73.4%~75.1%、77.8%~79.5%,显著高于空白组。此外,GAC作为载体富集大量功能微生物并加速AGS颗粒化进程,提高污泥浓度并改善沉降性。在GAC含量为20 mg/L时,污泥浓度高达6.7~6.9 g/L。GAC存在组别内污泥体积指数(SVI)低至50.2~58.3 mL/g。GAC提高了AGS内胞外聚合物(EPS)和胞内聚合物聚羟基烷酸酯(PHA)含量。碳源匮乏期,PHA降解产能用于微生物代谢及氮磷去除,提高AGC运行效率。微生物学分析表明GAC提高了与生物脱氮除磷相关微生物如Candidatus Accumulibacter、Zooglea的相对丰度。研究结果为AGS处理低C/N废水提供了一定的参考依据。

In view of the slow granulation process of aerobic granular sludge(AGS)and the low efficiency of low carbon/nitrogen(C/N)wastewater treatment,this study on the treatment of low C/N wastewater by sludge source granular activated carbon(GAC)enhanced AGS was carried out at the mesophilic temperature,and the effects of GAC on AGS effluent quality,sludge granulation process and microbial community characteristics were analyzed.The mechanism of GAC enhanced AGS treatment of low C/N wastewater was revealed.The results showed that GAC enhanced the treatment of low C/N wastewater by AGS.When the content of GAC was 20 mg/L,the removal efficiency of COD,NH_(4)^(+)-N and TP was as high as 92.6%~98.5%,73.4%~75.1%and 77.8%~79.5%,respectively,which is significantly higher than that of the blank.In addition,GAC as a carrier enriched a large number of microorganisms to accelerate the process of AGS granulation,increased sludge concentration and improved sedimentation.When the GAC content was 20 mg/L,the sludge concentration was as high as 6.7~6.9 g/L.The sludge volume index(SVI)in the GAC presence group was as low as 50.2~58.3 mL/g.GAC increased the contents of extracellular polymer(EPS)and polyhydroxyalkanoate(PHA)in AGS.During the period of carbon source scarcity,PHA degradation capacity is used for microbial metabolism and nitrogen and phosphorus removal to improve the operation efficiency of AGC.Microbiological analysis showed that GAC increased the relative abundance of microorganisms related to biological nitrogen and phosphorus removal,such as Candidatus Accumulibacter and Zooglea.The research results provided a certain reference basis for the treatment of low C shock N wastewater by AGS.