原水输水管道中消毒副产物生成势的影响因素

Influencing Factors of Disinfection By-Products Formation Potentials (DBPFPs) in Raw Water Conveying Pipelines

研究太湖流域某水厂原水输送管道沿程消毒副产物的生成势变化,并利用皮尔逊相关性分析其影响因素。结果表明:三氯甲烷生成势最高,二氯乙醛生成势最低;总生成势由高到低依次为三卤甲烷类、卤乙酸类、卤乙醛类;氯代副产物生成势的质量浓度约为溴代副产物的6.25倍;除二氯乙酸外的消毒副产物生成势出水相较于进水升高了18.61%~664.22%。此外,预氯化管段中各类副产物生成势及沿程升高比例基本高于未加氯管段,两管段变化趋势基本一致。温度与除一氯二溴甲烷外的三类甲烷类副产物生成势呈正相关;氨氮与各类副产物总生成势呈负相关;DOC与三卤甲烷类副产物生成势呈良好正相关,但与卤乙酸和卤乙醛类副产物生成势相关性不强,因而其可能适宜作为三卤甲烷生成势的指标;管道停留时间与大多数消毒副产物生成势正相关性良好。

The change of formation potentials of disinfection by-products(DBPFPs)in raw water pipelines of a waterworks in Taihu Basin was introduced.In addition,relationship between the change of DBPFPs and its impacting factors were analysed by Pearson correlation.Results showed,among the three types of DBPFPs,the formation potential of trichloromethane(THMFP)was the greatest while dichloroacetaldehyde was the lowest.The order of total formation potentials from high to low was trihalomethanes>haloacetic acids>haloacetaldehydes.The formation potential of chlorinated by-products was about 6.25 times of that of brominated by-products.Most of the DBPFPs except dichloroacetic acid increaseed obviously along raw water pipelines by 18.61%~664.22%in the effluent compared with that in the influent.Besides,the total DBPFPs in chlorinated pipe section were mainly much higher than that in nonchlorinated pipe section,and rising ratio as well.These two sections had similar changes.Water temperature had positive correlation with THMFP except chlorodibromomethane.Meanwhile ammonia nitrogen was negatively correlated with it.DOC was positively correlated with THMFP,but not with haloacetic acid and haloacetaldehyde,so that it could probably be used as an indicator of THMFP.Pipelines rention time was positively correlated with formation potentials of most C-DBPs.