处理垃圾渗滤液的SBR中微生物种群与污泥比阻

为了研究活性污泥法处理垃圾渗滤液时污泥过滤性能与微生物种群的关系,采用两组运行参数相同的SBR反应器对某垃圾焚烧发电厂的垃圾渗滤液进行处理,一组置于太阳光照下(SBR1),另一组置于室内黑暗处(SBR2).在运行过程中发现SBR1在第30~50 d出现了轮虫等捕食性后生动物,污泥比阻在第35 d出现下降;而SBR2在第40 d发生了丝状膨胀,污泥比阻一直上升.为了研究两组反应器中微生物种群的差异,取两反应器运行至第50 d的活性污泥进行高通量测序发现:SBR1真菌中Rozellomycota为优势菌门,相对丰度为83.71%.SBR2真菌中Basidiomycota和Trichosporon为优势菌门和菌属,相对丰度分别为99.84%和99.78%.SBR1中细菌丰度较SBR2高,Thauera是SBR1中主要细菌菌属,其相对丰度为39.35%;Planktosalinus、Thauera和Ottowia为SBR2中优势细菌菌属,其相对丰度分别为16.84%、16.23%和12.55%.SBR2中主要真菌和细菌菌属类型和丰度均与SBR1存在差异,可见活性污泥中的微生物种群结构是影响污泥过滤性能的主要因素,同时太阳光照会影响活性污泥反应器中的微生物种群结构.

Microbial Communities and Sludge Specific Resistance in Two SBRs Treating Leachate

The relationship between microbial populations and sludge filtration performance was studied when active sludge was used to treat the leachate from municipal solid waste incineration plants. Two SBRs (SBR1 and SBR2) were operated at the same conditions, except that SBR1 was exposed to the sunlight and SBR2 was in the dark. To identify the difference in microbial populations in two reactors, high-throughput sequencing method was used. On the 50^th day, the fungi abundance in SBR2 was higher than in SBR1. Phylum Rozellomycota became the dominant fungi in SBR1, whose relative abundance was 83.71%. Phylum Basidiomycota and Genus Trichosporon became only dominant fungi in SBR2, whose relative abundances were 99.84% and 99.78%, respectively. Bacterial abundance in SBR1 was higher than in SBR2. In SBR1, Thauera was the major bacterial genus, whose relative abundance was 39.35%. In SBR2, Planktosalinus, Thauera, and Ottowia were the major bacterial genera, whose relative abundances were 16.84%, 16.23%, and 12.55%. Rotifers and other predatory metazoan were detected on the 30^th-50^th days in SBR1 and sludge specific resistance began to decline on the 35^th day. Filamentous fungi bulking caused by Trichosporon resulted in a continuous increase in sludge specific resistance of SBR2. The dominant microbial communities (especially fungi) and sludge specific resistances in SBR1 and SBR2 were very different because of the effect of sunlight. Therefore, sunlight plays an important role on microbial communities and sludge characteristics.