有机负荷率对颗粒污泥处理高浓度畜禽养殖废水影响

Influence of Organic Loading Rate on Granular Sludge Treatment of High Concentration Livestock and Poultry Breeding Wastewater

通过改变进水有机负荷率(OLR)在序批式反应器内考察了OLR对颗粒污泥处理畜禽养殖废水去除污染物、颗粒化进程及微生物群落结构的影响。结果表明,适当提高OLR利于颗粒污泥去除畜禽废水内污染物并加速颗粒化进程,当OLR为3.0 kg/(m^(3)·d)时,COD和溶解性磷酸盐的去除效率分别高达92.6%~95.2%和92.6%~95.2%,均显著高于低OLR工况,且在此OLR下,污泥浓度最高,沉降性好,污泥粒径在0.3~0.7 mm占比69.8%,胞外聚合物(EPS)含量低至72.5 mg/g,但EPS内蛋白质/多糖的比值高达2.02。高OLR降低颗粒污泥处理畜禽养殖废水的效能并导致部分颗粒污泥解体。OLR同样能影响颗粒污泥内微生物多样性及群落结构,适当提高OLR增加了微生物多样性,并提高Proteobacteria和Bacteroidetes的相对丰度但降低了Planctomycetes的相对丰度,利于有机质和营养盐去除。本研究结果拓展了颗粒污泥的应用范围,并为颗粒污泥的快速启动提供一定技术支撑和理论依据。

By changing the organic loading ratio(OLR)of the influent water,the effects of OLR on the removal of pollutants,granulation process and microbial community structure of granular sludge treatment and livestock and poultry breeding wastewater were investigated in the sequential batch reactor.The results show that the appropriate increase of OLR is conducive to the removal of pollutants in livestock and poultry wastewater and accelerates the granulation process,when the OLR is 3.0 kg/(m^(3)·d),the removal efficiency of COD and dissolved phosphate is 92.6%~95.2%and 92.6%~95.2%,respectively,which are significantly higher than the low OLR working condition,and under this OLR,the sludge concentration is the highest,the sedimentation is good,and the sludge particle size is 0.3~0.7 mm,accounting for 69.8%.The extracellular polymer(EPS)content is as low as 72.5 mg/g,but the protein/polysaccharide ratio within EPS is as high as 2.02.High OLR reduces the efficiency of particulate sludge in treating livestock and poultry breeding wastewater and leads to the disintegration of some particulate sludge.OLR can also affect the microbial diversity and community structure in granular sludge.The appropriately increase of OLR can increase microbial diversity,and increase the relative abundance of Proteobacteria and Bacteroidetes,reduce the relative abundance of Planctomycetes,which is conducive to the removal of organic matter and nutrients.The results expand the application range of granular sludge and provide certain technical support and theoretical basis for the rapid start of granular sludge.