曝气对人工湿地胞外多糖累积影响及表征分析  

The Effect of Aeration on the Accumulation of Extracellular Polysaccharides and Its Structural Characterization Analysis in Constructed Wetland

作　　者：武晗琪 倪利晓[1,2] 杜存浩 WU Han-qi;NI Li-xiao;DU Cun-hao(College of Environment,Hohai University,Nanjing 210098,China;Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes,Ministry of Education,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学环境学院,江苏南京210098 [2]河海大学浅水湖泊综合治理与资源开发教育部重点实验室,江苏南京210098

出　　处：《环境科技》2020年第6期1-6,共6页Environmental Science and Technology

基　　金：国家自然科学基金(51779079,51979137);江苏省自然科学基金(BK20181313);江苏省水利科技项目(2018037)。

摘　　要：为更好理解曝气对垂直潜流人工湿地中胞外多糖累积作用,从2018年12月至2019年7月分别设置气水比0∶1,3∶1,6∶1,9∶1运行4组垂直潜流人工湿地,并提取胞外多糖进行表征分析。实验结果表明:在运行一定时间后,曝气能够缓解胞外多糖的累积。至运行结束,湿地中上层的胞外多糖浓度降低,底层的浓度激增。增加曝气强度能够显著降低胞外多糖的特性粘度。傅里叶红外光谱和SEM图证实胞外多糖是以β-糖苷键所相连,由O-H,C-H,C-O-C及=CH等多种基团组成的高度无定形的三维结构分子,表面有褶皱且存在细微孔洞。本研究推测胞外多糖特性粘度及与颗粒形成的胶状淤泥是造成堵塞的关键因子之一,为更深入地了解垂直潜流人工湿地堵塞原因提供依据。In order to gain a deep insight into the accumulation of extracellular polysaccharides in the vertical underwater constructed wetland,the present study ran four groups of submerged artificial wetlands with gas-water ratios of 0∶1,3∶1,6:1,and 9:1,respectively,from December 2018 to July 2019.The experimental results showed that aeration could alleviate the accumulation of extracellular polysaccharides over the period.The upper and middle layers saw a plunge in the concentration of the extracellular polysaccharide while the bottom layer experienced a surge in one at the end of the experiment.At the same time,the increase in aeration intensity can significantly reduce the intrinsic viscosity of extracellular polysaccharides.Fourier Infrared Spectroscopy and SEM images revealed that the extracellular polysaccharides which have a highly amorphous three-dimensional structure,home to various groups such as O-H,C-H,C-O-C and=CH,are connected byβ-glycosidic bonds.The molecular surface has wrinkle and micropores.The present study speculates that intrinsic viscosity of extracellular polysaccharides and colloidal sludge formed with particles play a key role in the clogging,hoping to deepen insight into vertical subsurface flow constructed wetlands blockage.

关 键 词：曝气 垂直潜流人工湿地 胞外多糖 结构表征 特性粘度 

分 类 号：X5[环境科学与工程—环境工程]