Abstract: The thermophilic (55℃) anaerobic digestion were conducted in order to investigate the constituents of extracellular polymeric substances (EPS), such as proteins and polysaccharides, and the influences of EPS on dewaterability of thickened sludge with humus soil (HS) or not. EPS were divided into two states i. e. dissolve-EPS and bound-EPS by centrifuge and heating respectively. During the whole process, dissolve-EPS, bound-EPS and Capillary suction time (CST) were detected. Results show that CST during digestion was markedly higher than the raw sludge. Statistical analysis suggest that CST and dissolve-EPS had a positive correlation; CST and bound-EPS had a negative correlation. After 21 days, dissolve polysaccharides in sludge with HS was less than without HS about 7% . However, dissolve proteins, bound-EPS did not have difference obviously in sludge. CST of sludge with HS was less than other about 25%. It indicates that dissolve polysaccharides had a strong influence of dewaterability of sludge.

Key words: humus soil, proteins, polysaccharides, extracellular polymeric substances, dewaterability

摘要： 为研究浓缩污泥中胞外聚合物的组分(蛋白质和多糖) 对污泥脱水性的影响, 对添加和未添加腐殖土的浓缩污泥进行21天的高温(55℃) 厌氧消化试验。通过离心和热提取的方法分别提取浓缩污泥中的溶解态胞外聚合物(dissolve-EPS)及结合态胞外聚合物(bound-EPS),并对污泥的溶解态和结合态的胞外聚合物以及脱水性(毛细吸水时间表征) 进行跟踪监测。结果表明, 高温厌氧消化过程中, 污泥毛细吸水时间随时间的增加逐渐增大。统计分析结果表明, 污泥毛细吸水时间与溶解态蛋白质和多糖有显著地正相关(0.868, 0.959), 与结合态蛋白质和多糖有显著地负相关(-0.783, -0.831)。厌氧消化21天后, 添加腐殖土的污泥中溶解态多糖比未添加的低 7% 左右, 而溶解态蛋白质、结合态蛋白质和多糖没有明显变化。添加腐殖土的污泥毛细吸水时间比未添加的降低了25% , 这表明, 污泥中溶解态多糖对污泥的脱水性起主要作用。

关键词: 腐殖土, 蛋白质, 多糖, 胞外聚合物, 脱水性