食品废水A/O工艺的低温启动阶段膨胀污泥的微生物群落解析

污泥膨胀是污水处理工艺启动和运行中棘手的问题,食品废水采用A/O工艺进行低温下启动运行时,出现了污泥膨胀的现象,研究对A/O工艺段水质进行了分析,构建了16S r DNA克隆文库.通过对膨胀污泥微生物群落解析,探讨了污泥膨胀和工艺调控的关系.研究表明,厌氧膨胀污泥中Proteobacteria占总的细菌数的63.51%,Chloroflexi为16.22%,其中Thauera sp.占到总的细菌数的20.27%;好氧膨胀污泥中Proteobacteria占总的细菌数的36.08%,Chloroflexi为24.74%,Bacteroidetes为7.22%,出现了与污泥膨胀有关的细菌Uncultured Nocardia,Uncultured Leptolyngbya sp.,Thauera sp..导致污泥膨胀的主要原因是工艺的进水温度低,厌氧段厌氧程度不够,可生化性差,部分重金属超标,好氧段的曝气量不足.建议通过调控工艺的进水温度,提高厌氧段的厌氧程度,提高好氧段的曝气量,可以有效地控制污泥膨胀.

Microbial community analysis of bulking sludge during food wastewater A/O process in low temperature

It is difficult to resolve the problem of sludge bulking. The A/O process was applied for the food wastewater treatment. It is found that sludge would expanded in the low temperature. The water quality was analyzed, and 16SrDNA clone library was built. Through the analysis the microbial community, the relationship of sludge bulking and process control was studied. It showed that the percent of Proteobacteria was 63.51%, Chloroflexi was 16.22% and Thauera sp. was 20.27% in anaerobic sludge bulking. The percent of Proteobacteria was 36.08%, Chloroflexi was 24.74% and Bacteroidetes was 7.22% in aerobic sludge bulking. In the same time, Uncultured Nocardia, Uncultured Leptolyngbya sp., Thauera sp. were found which are related with sludge bulking. The low temperature was the main external ecological factors. There are several reasons to cause the sludge bulking, such as the lack of anaerobic degree in anaerobic period , poor biochemical, high concentration of heavy metal and oxygen deficiency in aerobic period. It is showed that sludge bulking would be control effectively when we regulated the process of inlet temperature, improve the anaerobic degree and aerationSfluxes.