SBR处理大蒜废水影响因素和微生物群落特征

Influencing Factors and Microbial Community Characteristics of SBR Treatment of Garlic Wastewater

采用AO工艺,利用SBR反应器,以高浓度大蒜废水(COD>7 000 mg/L)为对象,基于控制变量法探究曝气量、进水pH、搅拌速度对污染物去除效果的影响,明确微生物功能菌群和多样性对污染物降解的作用。曝气量和进水pH对污染物去除效果影响显著。系统中以具有脱氮除磷降解有机物功能的拟杆菌门(Bacteroidetes)、变形菌门(Proteobacteria)为主,两者总体细菌相对丰度分别达到了97.82%和98.41%,明显高于接种污泥的56.48%。科水平A2、A3和A1的样本间距离分别为0.894 05和0.875 83,说明其在物种丰度分布上有较大差异,A2、A3中的优势菌科与A1中的优势菌科相差甚大。A2和A3前9类优势菌科基本一致,但其样本间距离为0.233 72,说明物种丰度分布略有差异,两个反应器处理效果会略有不同。A2和A3具有多种功能,其中化能异养和需氧化能异养作用的功能丰度均大于30%。SBR反应器在曝气量为0.3 L/min,进水pH为7.0,搅拌速度为70 r/min的条件下,污染物去除率达到92%以上。

In the AO process,the SBR reactor was used to investigate the effects of aeration,influent pH and agitation rate on the pollutant removal by a controlled variable method using high-concentration garlic wastewater(COD>7 000 mg/L),which clarified the role of microbial functional flora and diversity on pollutant degradation.The aeration and influent pH have a significant effect on pollutant removal.The system was dominated by Bacteroidetes and Proteobacteria,which have the function of nitrogen and phosphorus removal and degradation of organic matter,and their overall relative abundance reached 97.82% and 98.41%,respectively.The effect was significantly higher than the 56.48% of the inoculated sludge.The intersample distances of family levels A2,A3 and A1 were 0.894 05 and 0.875 83,respectively,indicating a large difference in the distribution of species abundance with the dominant families in A2 and A3 differing considerably from those in A1.The first nine dominant families of A2 and A3 were essentially the same,but their inter-sample distance was 0.233 72,indicating that the species abundance distribution was slightly different and that the effect of the two reactor treatments would be slightly different.The A2 and A3 are multifunctional,with both chemoheterotrophic and oxidationdemanding heterotrophic interactions in greater than 30% functional abundance.The SBR reactor achieved over 92% pollutant removal at an aeration rate of 0.3 L/min,a feed water pH of 7.0 and a stirring speed of 70 r/min.