Abstract:
The increasing demand for trichloroisocyanuric acid (TCCA) in swimming pool disinfection highlights the need to evaluate its applicability in terms of disinfection by-product (DBP) formation. Nevertheless, there is limited understanding of DBP formation and control during TCCA disinfection, particularly concerning the effects of various management parameters. This study aimed to fill this knowledge gap by comprehensively investigating DBP formation during TCCA chlorination, with a particular focus on assessing the contribution and interaction of influencing factors using Box-Behnken Design and response surface methodology. Results indicated that the concentrations of trichloroacetaldehyde, chloroform, dichloroacetic acid, trichloroacetic acid, and dichloroacetonitrile produced by TCCA disinfectant were 42.5%, 74.0%, 48.1%, 94.7% and 42.6% of those by the conventional sodium hypochlorite disinfectant, respectively. Temperature exhibited the most significant impact on chloroform formation (49%), while pH played a major role in trichloroacetaldehyde formation (44%). pH2 emerged as the primary contributor to dichloroacetic acid (90%) and trichloroacetic acid (93%) formation. The optimum water quality conditions were determined based on the minimum total DBPs (pH = 7.32, Temperature = 23.7 °C, [Cl-] = 437 mg/L). Chlorine dosage and contact time exhibited greater influence than precursor concentration on chloroform, dichloroacetonitrile, trichloroacetaldehyde, trichloroacetic acid, and total DBPs. Although the interaction between water quality parameters was weak, the interaction between disinfection operating parameters demonstrated substantial effects on DBP formation (8.56-19.06%). Furthermore, the DBP predictive models during TCCA disinfection were provided for the first time, which provides valuable insights for DBP control and early warning programs.
摘要:
游泳池消毒中对三氯异氰尿酸(TCCA)的需求不断增加,这凸显了需要评估其在消毒副产物(DBP)形成方面的适用性。然而,对TCCA消毒过程中DBP的形成和控制的了解有限,特别是关于各种管理参数的影响。本研究旨在通过全面调查TCCA氯化过程中DBP的形成来填补这一知识空白,特别关注使用Box-Behnken设计和响应面方法评估影响因素的贡献和相互作用。结果表明,三氯乙醛的浓度,氯仿,二氯乙酸,三氯乙酸,TCCA消毒剂产生的二氯乙腈为42.5%,74.0%,48.1%,其中94.7%和42.6%通过常规次氯酸钠消毒剂,分别。温度对氯仿形成的影响最大(49%),而pH在三氯乙醛形成中起主要作用(44%)。pH2是二氯乙酸(90%)和三氯乙酸(93%)形成的主要贡献者。根据最小总DBPs(pH=7.32,温度=23.7°C,[Cl-]=437mg/L)。氯用量和接触时间对氯仿的影响大于前体浓度,二氯乙腈,三氯乙醛,三氯乙酸,和总DBPs。尽管水质参数之间的相互作用较弱,消毒操作参数之间的相互作用对DBP形成有重大影响(8.56-19.06%)。此外,首次提供了TCCA消毒过程中的DBP预测模型,这为DBP控制和预警计划提供了有价值的见解。