二氧化氯杀灭拟柱孢藻的研究

对于来自某饮用供水水库的拟柱孢藻,研究二氧化氯投加量、藻的初始浓度、pH值、有机物含量和氨氮含量对二氧化氯杀灭拟柱孢藻的效果的影响,探讨二氧化氯氧化与混凝工艺结合的去除拟柱孢藻的最佳工艺条件。结果表明,拟柱孢藻的杀灭率随着二氧化氯投加量增大而提高,随着pH的升高及有机物含量的增大而下降;杀藻量随着藻初始浓度的增大而增大。氨氮对二氧化氯杀灭拟柱孢藻基本没有影响。对于以拟柱孢藻为优势藻的某饮用供水水库原水,二氧化氯氧化与混凝工艺结合除藻的最佳工艺条件为:二氧化氯投加量0.5 mg/L,聚合氯化铝15 mg/L,二氧化氯与混凝剂一起投加。在此条件下,除藻率为98.90%,余浊为1.59 NTU。工艺条件正交试验的直观分析说明影响除藻率的因素依次为:二氧化氯投加量>混凝剂投加量>投加顺序。

Killing Cylindrospermopsis with Chlorine Dioxide

Cylindrospermopsis breeding in water bodies such as reservoir and lakes due to eutrophication negatively affects tap water production process.This paper reports the use of chlorine dioxide to remove Cylindrospermopsis from tap water at a bench-scale test,in which factors of dosage of chlorine dioxide,initial algal concentration,pH,organism,and ammonia nitrogen concentration were investigated.Result showed that removal rate of Cylindrospermopsis increased with increased dosage of chlorine dioxide,and decreased with increased pH value and organism concentration;but the existence of ammonia nitrogen had no influence on Cylindrospermopsis removal.In addition,optimum condition of coagulation process combined with addition of chlorine dioxide was studied using polymeric aluminum chloride(PAC) as a coagulant.The best result achieved 98.90% of Cylindrospermopsis removal and 1.59 NTU of residual turbidity.Analysis with orthogonal experiment indicated that the magnitude order affecting the removal of Cylindrospermopsis was dosage of chlorine dioxide followed by dosage of the coagulant;effect of the order of addition(PAC,chlorine dioxide) was still minor.