紫外-氯对细菌的协同消毒效果

Synergistic Disinfection Effect on Microbes by a Combination of Ultraviolet-Chlorin

研究了紫外-氯的联合作用对大肠杆菌和芽孢的消毒效能。相对于单独紫外消毒,紫外-氯能显著提高芽孢的消毒效率而对大肠杆菌的消毒效果影响不大。大肠杆菌对紫外和氯均比较敏感,而芽孢则需较高辐照剂量的紫外或氯才能达到相同的消毒效果。紫外-氯较紫外-过氧化氢能更有效地产生羟基自由基,但当氯离子浓度较高时部分羟基自由基与之反应生成氯自由基。紫外-氯对芽孢消毒的协同作用可部分归因于在此过程中产生的羟基自由基及形成的氯自由基。

By using E.Coli and spores of B.Sub as model surrogates, the impact of UV combine with chlorine on the microbes disinfection was investigated. Compared to UV disinfection, the combination of UV and chlorine could enhance the disinfection efficiency of spores significantly whereas no effects on E.Coli. To achieve the same disinfection effects, more dosage of UV or chlorine was required to kill spores than E.Coli, as the latter is sensitive to both UV and chlorine. During the UV irradiation, chlorine underwent photolysis and produced much more amount of hydroxyl radicals than that of hydrogen peroxide, meanwhile hydroxyl radicals reacted with chloride ion to form chlorine radicals once the solution contain more chlorine ion. The synergistic disinfection effects of UV -chlorine on spores could be attributed to the higher amount of hydroxyl radicals and chlorine radicals formed during the process.