UV和H2 O2联合消毒灭活饮用水中大肠杆菌研究

以大肠杆菌为研究对象,对单独紫外线(UV)、H2O2及两者不同组合方式的灭活效果进行了分析.结果表明,单独H2O2对大肠杆菌基本无灭活效果,加入浓度为20 mg·L-1的H2O2接触时间为30 min时,灭活率仅为0.02个对数级;单独UV工艺可在一定程度上灭活大肠杆菌,紫外线剂量为10 mJ·cm-2时,灭活率可达到4.51个对数级.紫外线和H2O2联合消毒在一定程度上提高了消毒效果,且不同的组合方式对灭活效果有很大的影响.先UV后H2O2消毒效果优于先H2O2后UV,当紫外线剂量为5 mJ·cm-2时,加入H2O2分别反应2.5、5、10、20 min后,两者的灭活率分别较单独UV消毒增加0.09、0.35、0.38、0.68和0.01、0.07、0.14、0.53个对数级.而UV与H2O2同时消毒效果优于UV与H2O2顺序消毒,当紫外线剂量为5 mJ·cm-2时,加入H2O2反应20 min后,灭活率较UV-H2O2和H2O2-UV工艺分别增加了0.43和0.58个对数级.随着紫外线强度的增加,大肠杆菌的灭活效果不断提高.

Study on UV and H2 O2Combined Inactivation of E. coli in Drinking Water

The inactivation effect of E. coli with both UV irradiation and hydrogen peroxide disinfection individually and in different combination modes was investigated. The results showed that hydrogen peroxide alone caused hardly any inactivation of E. coli. Only 0.02 lg inactivation was achieved by hydrogen peroxide with concentration of 20 mg·L^-1 and contact time of 30 min. UV irradiation was able to inactivate E. coli to a certain extent. The inactivation reached 4.51 lg at a UV dose of 10 mJ·cm^-2. The combination of UV and H₂ O₂ could significantly improve the inactivation effect and the different combination modes affected the inactivation effect. The inactivation effect of UV-H₂ O₂ was better than that of H₂ O₂-UV. The inactivation was increased by 0.09, 0.35, 0.38, 0.68 lg and 0.01, 0.07, 0.14, 0.53 lg when compared to the treatment with solely UV irradiation, respectively, at UV dose of 5 mJ·cm^-2 with hydrogen peroxide at contact time of 2.5, 5, 10, 20 minutes. UV/H₂ O₂ achieved better results than sequential disinfection. The inactivation was enhanced by 0.43 lg and 0.58 lg when compared to UV-H₂ O₂and H₂ O₂-UV, respectively, at UV dose of 5 mJ·cm^-2 with hydrogen peroxide at contact time of 20 minutes. The inactivation of E. coli increased with the enhancement of UV radiation intensity.