再生水为水源时微润管堵塞现象及其原因探究

Exploration of the Moistube Blockage Phenomenon and Reasons with Reclaimed Water

为探究以再生水为水源时微润管的堵塞情况及其原因,对微润管进行了为期1320 h的堵塞评价试验。与自来水水源相比,再生水为水源时微润管的堵塞程度更严重。再生水工况下,试验运行312 h后,微润管开始出现严重堵塞,管段出流量整体呈现“缓慢下降-急剧下降-缓慢下降”的分段式下降趋势。对再生水工况下,不同堵塞程度的管段进行微润管管壁生物膜组分(胞外聚合物,Extracellular Polymeric Substances,EPS)含量及微生物群落变化分析。结果表明EPS中的多糖及蛋白质是导致微润管堵塞的关键诱因,两者与堵塞程度均存在“S形曲线”相关关系,呈现出“敏感-弱敏感-敏感”的变化趋势,其中多糖含量更高,与堵塞程度相关关系更为密切。随着堵塞程度加深,能够大量分泌EPS的变形菌门微生物成为优势菌门,加剧了微润管的堵塞。研究可为探明微润管微生物堵塞现象及机理提供理论依据。

In order to explore the blockage situation and causes of the micro-moistening pipe with reclaimed water as the water source,a 1320 h blockage evaluation test was carried out on the micro-moistening pipe.Compared with tap water source,the blockage degree of micro water pipe was more serious when the reclaimed water was the water source.Under the condition of reclaimed water,after 312 h of test operation,the micro-moistening pipe began to be seriously blocked,and the discharge of the pipe showed a segmented downward trend of“slow decline-sharp decline-slow decline”as a whole.Under the condition of reclaimed water,the contents of biofilm components(Extracellular polymer,EPS)and the changes of microbial community in the microwetting tube wall were analyzed.The results showed that polysaccharides and proteins in EPS were the key factors leading to the blockage of micromoist tube.There was an s-shaped curve correlation between them and the degree of blockage,showing a change trend of“sensitively-weak sensitively-sensitive”,in which the polysaccharide content was higher and the correlation with the degree of blockage was closer.With the deepening of the blockage,proteobacteria that can secrete a large amount of EPS become the dominant bacteria,aggravating the blockage of the micro-moistening tube.This study can provide a theoretical basis for exploring the phenomenon and mechanism of microbial blockage in micromoist tubes.