污水处理厂冬季硝化强化与微生物种群分析

Nitrification enhancement and microbial community structure analysis for a full-scale wastewater treatment plant in winter

针对冬季低温抑制微生物活性导致硝化菌流失的问题,在实际污水处理厂通过两组10万m^3/d的反应池平行运行,考察了延长污泥龄对污水处理厂的出水水质、硝化速率和微生物种群结构的影响.研究结果表明,拉前延长污泥龄能够明显提升低温阶段COD、氨氮和TN的去除效率,硝化速率为对照组的3倍.焦磷酸测序结果表明,延长污泥龄后系统的微生物种群丰度和多样性均显著提高;氨氧化功能菌属Nitrosomonas(1.46%)和亚硝酸盐氧化功能菌属Nitrospira(0.13%)较对照组分别提高了12和13倍;反硝化相关菌属Hyphomicrobium、Thauera、Zoogloea等的相对丰度也明显增加.提前延长污泥龄这一方法能够实现硝化菌的富集,进而提升污水处理的硝化和脱氮效率.

Two100,000m3/d bioreactors in a full-scale wastewater treatment plant(WWTP)were operated in parallel toinvestigate the effect of prolonging sludge retention time(SRT)on effluent quality,nitrification rate and microbialcommunity structure in winter.The results showed that prolonging SRT in advance greatly enhanced removal efficienciesof COD,ammonia nitrogen and total nitrogen,as well as increased the nitrification rate as thrice of the control bioreactor.Further analysis by pyrosequencing showed that the abundance and diversity of microbial populations significantlyincreased by prolonging SRT.Compared to the control bioreactor,the relative abundance of Nitrosomonas(ammoniaoxidizing bacteria,1.46%)and Nitrospira(nitrifying oxidizing bacteria,0.13%)were increased by12and13times,respectively.Prolonging SRT also enriched denitrifying bacteria,including Hyphomicrobium,Thauera and Zoogloea,etc.These results indicated that prolonging SRT in advance significantly enhanced nitrifying microbial communities,whichresulted in the enhancement in the nitrification and denitrification efficiency of the full-scale WWTP.