Abstract:
Disinfection is essential to swimming pool water (SPW) quality. Peracetic acid (PAA) has attracted attention for water disinfection for advantages such as less formation of regulated DBPs. Persistence kinetics of disinfectants is difficult to elucidate in pools because of the complex water matrix stemming from body fluid loadings from swimmers and long residence times. In this research, the persistence kinetics of PAA was investigated in SPW benchmarked against free chlorine, use bench-scale experiments and model simulation. Kinetics models were developed to simulate the persistence of PAA and chlorine. The stability of PAA was less sensitive to swimmer loadings than chlorine. An average swimmer loading event reduced the apparent decay rate constant of PAA by 66 %, a phenomenon that diminished with increasing temperatures. L-histidine and citric acid from swimmers were identified as main retardation contributors. By contrast, a swimmer loading event instantaneously consumed 70-75 % of the residual free chlorine. The required total dose of PAA was 97 % less than chlorine under the 3-days cumulative disinfection mode. Temperature was positively correlated with disinfectant decay rate, with PAA being more sensitive than chlorine. These results shed light on the persistence kinetics of PAA and its influential factors in swimming pool settings.
摘要:
消毒对于游泳池水(SPW)质量至关重要。过氧乙酸(PAA)因其优点(例如较少形成受调节的DBPs)而引起了人们对水消毒的关注。由于复杂的水基质源于游泳者的体液负荷和较长的停留时间,因此很难在游泳池中阐明消毒剂的持久性动力学。在这项研究中,PAA的持久性动力学在SPW中以游离氯为基准进行了研究,使用台架实验和模型模拟。建立了动力学模型来模拟PAA和氯的持久性。PAA的稳定性对游泳者负荷的敏感性低于氯。平均游泳者负荷事件使PAA的表观衰减速率常数降低了66%,随着温度升高而减弱的现象。来自游泳者的L-组氨酸和柠檬酸被确定为主要的阻滞因素。相比之下,游泳者装载事件瞬间消耗了70-75%的残余游离氯。在3天累积消毒模式下,所需的PAA总剂量比氯低97%。温度与消毒剂腐烂率呈正相关,PAA比氯更敏感。这些结果揭示了游泳池环境中PAA的持久性动力学及其影响因素。