氯、二氧化氯对氯胺消毒管网硝化作用控制效果对比

采用2台串联BAR模拟给水管网系统, 通过对余氯、NH₄⁺-N、NO₂^--N、NO₃^--N、DO、HPC及AOB等指标检测, 评价氯和二氧化氯2种消毒剂对氯胺消毒管网中硝化作用的控制效果.研究结果表明:二氧化氯比等量氯更易提高管网中余氯质量浓度和DO质量浓度;氯消毒阶段NH₄⁺-N降解, NO₂^--N和NO₃^--N积累, 而投加二氧化氯后可有效控制硝化作用;与投加氯消毒相比, 投加等质量浓度 (0.6 mg/L) 二氧化氯时, 第1台BAR中悬浮和生物膜中HPC分别降低了2.54 log和1.63 log, 悬浮及生物膜中AOB降低约1 log;二氧化氯能对AOB起到控制灭活效果而等量氯对其几乎没有灭活效果, 在控制供水管网硝化作用方面, 二氧化氯与氯胺联用的消毒效果优于氯与氯胺.

Disinfectant Efficacy of Chlorine and Chlorine Dioxide in Nitrification Control in Water Distribution Systems

Two biofilm annular reactors (BAR) in series were adopted in the study, and the effects of chlorine and chlorine dioxide disinfection on nitrification were compared by analyzing residue chlorine, NH₄⁺-N, NO₂^--N, NO₃^--N, DO, HPC and AOB.The results showed that chlorine dioxide was more effective than chlorine in enhancing the effluent concentration of residue chlorine and DO.The concentration of NH₄⁺-N was droped while NO₂^--N and NO₃^--N were increased during the stage of chlorine, but not happening during the stage of chlorine dioxide.Compared with equivalent chorine (0.6mg/L) , the chlorine dioxide was more effective in removing suspended and boifilm HPC with 2.54 log and 1.63 log reductions, respectively, and both suspended and biofilm AOB with 1 log reduction.Chlorine was ineffective in controlling AOB.Therefore, the effect of chorine dioxide combined with chloramine was better than chorine combined with chloramine in mitigating nitrification in distribution systems.