好氧颗粒污泥技术处理乡镇污水应用

Application of Aerobic Granular Sludge Technology on Treatment of Villages and Towns Sewage

为研究好氧颗粒污泥技术是否适用于处理乡镇污水,采用该技术对处理规模为400 m^3d的乡镇污水处理厂进行改造,考察了污泥颗粒化过程、污染物去除效果及接种絮状污泥与好氧颗粒污泥微生物群落结构差异.结果表明,以进料负荷的交替变化作为调控措施,反应器启动后第13天污泥出现颗粒化,颗粒污泥平均粒径0.499 mm;启动第40天污泥完全颗粒化,颗粒污泥平均粒径1.336 mm.完全颗粒化后SBR反应器内ρ(MLSS)稳定在8~12 gL,SVI维持在25~40 m Lg,出水ρ(COD_(Cr))、ρ(NH_3-N)、ρ(TN)始终满足GB 18918—2002《城镇污水处理厂污染物排放标准》一级A标准要求.群落结构的研究结果表明,相比于接种絮状污泥,好氧颗粒污泥群落丰富度和多样性均明显减少,反硝化功能菌和聚磷菌丰度显著增加;在好氧颗粒污泥中,Nitrosomonas(亚硝化单胞菌属)、Nitrospira(硝化螺旋菌属)是主要的硝化功能菌;Dechloromonas、Clostridium sensu stricto 13(梭菌属)是主要的反硝化细菌;Aeromonas(气单胞菌属)、Clostridium sensu stricto 13(梭菌属)是主要的聚磷菌;Uncultured Xanthomonadaceae、Comamonas(丛毛单胞菌属)、Zoogloea(动胶菌属)是降解有机物的主要菌种,其中Comamonas(丛毛单胞菌属)、Zoogloea(动胶菌属)也是好氧污泥颗粒化过程中的关键菌株.

Aerobic granular sludge technique was used to treat villages and towns sewage to access its feasibility for a reconstructing full-scale sewage treatment plant(400 m 3 d).The process of sludge granulation,pollutants removal and community differences between inoculated and granular sludge were investigated.Results showed that the granulation of sludge occurred on 13 th day,and the average size of sludge reached 0.499 mm in diameter by a method of alternative feed loading.Completely granulated sludge was observed on 40 th day,and the average size was up to 1.336 mm in diameter.Meanwhile,theρ(MLSS)and SVI were 8-12 g L and 25-40 mL g in the reactor,respectively.The effluent COD Cr,ammonia nitrogen,total nitrogen met A standard of the first level of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB 18918-2002)in China.Compared with inoculated floc sludge,the species richness and diversity of microbial community of aerobic granular sludge were significantly reduced,whereas the abundance of bacterial communities for denitrification and phosphorus removal was significantly increased.In the aerobic granular sludge,Nitrosomonas and Nitrospira are the main nitrifying bacteria;Dechloromonas and Clostridium sensu stricto 13 are the main denitrifying bacteria;Aeromonas and Clostridium sensu stricto 13 are the main bacteria for phosphorus removal;Uncultured Xanthomonadaceae,Comamonas,Zoogloea are the main bacteria for organics removal and are also the key bacteria for sludge granulation.