强化造粒条件下颗粒污泥中EPS不同组分的空间分布特征

Spatial Distribution Characteristics of Different EPS Components in Granular Sludge under the Strengthening Granulation Condition

采用多重荧光染色方法分析强化造粒条件下（不同时间段投加PAC）好氧颗粒污泥形成过程中胞外聚合物（extracellular polymeric substances,EPS）各组分的空间分布特征。研究发现：强化造粒条件下污泥完全颗粒化进程与对照组相比,所需时间明显缩短,粒径更大,含水率、比重、强度更优,且颗粒结构更规则紧密。EPS不同组分空间分布分析表明：α-呋喃葡萄糖、α-甘露糖主要分布在颗粒外侧,蛋白质在整个颗粒污泥断面均有分布,PAC投加对它们的分布影响较小,但对β-D-呋喃葡萄糖、脂类以及死细胞和活细胞在颗粒污泥中的分布有明显的影响;其中在1-7 d投加PAC,死细胞和β-D-呋喃葡萄糖主要集中在颗粒污泥外侧,活细胞和脂类主要分布在颗粒污泥内部,而8-14 d投加PAC,上述情况刚好相反;对照组（不投加PAC）颗粒污泥EPS各组分的空间分布与推迟PAC投加时间后的情况基本相似。

Multiple fluorescent staining was used to study the spatial distribution characteristics of extracellular polymeric substances（EPS） components which was produced in the process of the formation of aerobic granular sludge under the condition of strengthening granulation（dosing PAC in different periods）. The results showed that compared with the control group,the time for the aerobic granular sludge completely granulation under strengthening granulation condition significantly shorten;the size of the granules become larger;the intensity,specific gravity,moisture content of the granules become better;and the structure of the granules become more regular and closer. Spatial distribution of EPS components showed that proteins are distributed throughout the granules section,and α-polysaccharides are located at the outer layer of granules. PAC dosing has smaller influence on the distribution of proteins and α-polysaccharides,but has obvious effect on the distribution of β-polysaccharides,lipids,dead cells and live cells. After dosing PAC in 1-7 days,dead cells and β-polysaccharides are mainly located at the outer layer of the aerobic granules,while live cells and lipids are mainly located at the inside layer of the granules. However,the phenomenon become reversed after dosing PAC in 8-14 days. In the control group（without dosing PAC）,the spatial distribution of EPS components of granules are similar with the groups which postpone the PAC dosing time.