紫外线-茶多酚/次氯酸钠联合消毒管网微生物特性分析

紫外线对微生物的杀灭效果较好，但持续性差，引入茶多酚作为辅助消毒剂，采用管网动态模拟系统，对比了紫外线-茶多酚联合消毒和紫外线-次氯酸钠联合消毒后管网微生物的总量、群落分布和有机物荧光特性变化。结果表明，紫外线-茶多酚联合消毒对微生物的灭活效果比紫外线-次氯酸钠联合消毒更好，并且对致病菌和耐氯性细菌也有很强的杀灭能力。紫外线-茶多酚联合消毒后，酪氨酸类物质荧光和类腐殖酸物质荧光特性产生变化，说明这2类物质含量大量减少，可能会影响微生物的生长；此外，管壁生物膜中出现了儿茶素、表儿茶素类物质，这说明茶多酚与管壁微生物发生了相互作用；紫外线-次氯酸钠联合消毒后酪氨酸类的荧光特征峰发生蓝移，这说明次氯酸进入微生物内发挥氧化作用。

Analysis of microbial characteristics in pipe network with ultraviolet & tea polyphenols or ultraviolet & sodium hypochlorite combined disinfection

Ultraviolet (UV) has a good disinfection performance on microorganisms but with a weak durative. Tea polyphenols (TP) or sodium hypochlorite was used as an adjunct disinfectant for UV disinfection. In the dynamic simulation system of pipe network, the variations of microbial biomass, microbial community structure and organic matter fluorescence were compared between UV-TP and UV-NaClO combined disinfections. Results showed that the former had a better inactivation effect on microorganisms than the later, and a stronger cell-killing ability against pathogenic bacteria and chlorine-resistant bacteria. The change in fluorescence characteristics of tyrosine and humic acid after UV-TP combined disinfection indicated that the contents of these two substances were greatly reduced, which may affect the growth of microorganisms. In addition, the appearance of catechins and epicatechins in the biofilm on the pipe wall indicated that the occurrence of interaction between tea polyphenols and microorganisms. After UV-NaClO combined disinfection, a blue shift happened on the fluorescence characteristic peaks of tyrosines, which indicated that hypochlorous acid entered the cell of microorganisms and played an oxidation role accordingly.