【摘要】 研究了紫外光-氯联用消毒工艺削弱二级出水氯消毒拖尾程度.考察了紫外光-氯使用顺序、pH、氯投量、紫外光剂量等因素对氯消毒大肠杆菌动力学曲线的影响.SS浓度对"拖尾现象"有显著影响,降低SS浓度能够有效提高拖尾区灭活率.紫外光-氯联用消毒能提高一级反应区的灭活速率1.08～1.25倍,并将拖尾区灭活率提高2～2.5个对数级,二者存在明显协同作用.UV/HOCl方式效果优于HOCl/UV方式.降低pH,提高氯投量将加快一级反应区消毒速度而更快进入拖尾区.紫外光剂量变化对拖尾区开始时间没有显著影响.更多还原

【Abstract】 Combined disinfection with UV radiation and chlorination was investigated to reduce the extend of tailing in chlorination of secondary effluent. Impacts of exposure sequences to UV and chlorination,pH,and dosages of chlorine and UV on the kinetic curves of E. coli were evaluated.Suspended solids significantly affect the extent of the "tailing" phenomenon. Reduction of SS considerably increased the log-kill in the tailing region. Combined disinfection with UV radiation and chlorination substantially increased the disinfection rate by 1.08~1.25 times in the fast-order region,and consequently increased the log-kill by 2~2.5 level in the tailing region. The synergistic effects of combined disinfection with UV radiation and chlorination were confirmed. The UV-HOCl sequence resulted in a higher inactivation rate than the HOCl-UV sequence. Lowering pH and/or increasing chlorine dosage magnified the enhancements in first-order disinfection rate,and shortened the start time of the tailing region. Variation in UV dose had no significant effects on the start time of the tailing region.更多还原