EnviroChem Services, Cookeville, TN, United States.
Brown and Caldwell, Atlanta, GA, United States.
Sci Total Environ. 2023 Aug 15;886:163937. doi: 10.1016/j.scitotenv.2023.163937. Epub 2023 May 5.
Periods of drought coupled with increasing population growth have prompted increased interest in potable water reuse in Gwinnett County, Georgia, USA. However, such inland water recycling facilities are challenged with treatment approaches where reverse osmosis (RO) membrane concentrate disposal is a barrier to implementation of potable reuse. To evaluate alternative treatment processes, testing of two side-by-side pilot systems using multi-stage ozone and biological filtration without RO was conducted to compare indirect potable reuse (IPR) to direct potable reuse (DPR). Two water sources were investigated-influent from Lake Lanier for the IPR pilot, and a blend of 25 % reclaimed water mixed with lake water (75 %) for the DPR pilot. To assess the nature of organic matter removed during potable reuse, excitation-emission matrix (EEM) fluorescence spectroscopy/PARAllel FACtor (PARAFAC) analyses were examined as a fingerprinting tool. The objectives were to determine (a) if a DPR scenario, when preceded by advanced wastewater treatment, could achieve drinking water quality comparable to IPR and (b) if water quality monitoring using EEM/PARAFAC methods could predict results for DPR and IPR water quality, comparable to parameters obtained in a supplementary study that required more expensive, time-consuming, and complicated analytical techniques. Sample scores representing relative concentrations of fluorescing organic matter derived from the EEM-PARAFAC model decreased in the order of reclaimed water > lake water > DPR pilot > IPR pilot, demonstrating that EEM/PARAFAC could distinguish between DPR and IPR water quality. An assessment of a comprehensive list of individual organic compounds (reported separately) validated that blend ratios of 25 % reclaimed water, or higher mixed with lake water (75 %) did not meet primary and secondary drinking water standards. Likewise, in this study, EEM/PARAFAC analysis demonstrated the 25 % blend did not provide drinking water quality indicating this simple, inexpensive method could be used for potable reuse monitoring.
在美国佐治亚州格温内特县，由于干旱期与人口增长期相重合，人们对饮用水再利用的兴趣日益浓厚。然而，内陆水资源循环利用设施面临的挑战是，反渗透（RO）膜浓缩物的处理方式成为实现饮用水再利用的障碍。为了评估替代处理工艺，并排进行了两个中试系统的测试，该系统使用多阶段臭氧和生物过滤而不使用 RO，以比较间接饮用水再利用（IPR）和直接饮用水再利用（DPR）。研究了两种水源-用于 IPR 中试的莱纳湖进水，以及 DPR 中试的 25%再生水与湖水（75%）混合的混合水。为了评估饮用水再利用过程中去除的有机物的性质，使用激发-发射矩阵（EEM）荧光光谱/PARAllel FACtor（PARAFAC）分析作为一种指纹工具进行了检查。目标是确定（a）在先进的废水处理之前，DPR 方案是否可以达到与 IPR 相当的饮用水质量，以及（b）如果使用 EEM/PARAFAC 方法进行水质监测是否可以预测 DPR 和 IPR 水质的结果，与需要更昂贵、耗时和复杂分析技术的补充研究中获得的参数相当。EEM-PARAFAC 模型衍生的荧光有机物相对浓度的样品得分顺序为再生水>湖水>DPR 中试>IPR 中试，表明 EEM/PARAFAC 可以区分 DPR 和 IPR 水质。对一份综合的单个有机化合物列表（单独报告）的评估验证了 25%的再生水与湖水（75%）的混合比例不符合主要和次要饮用水标准。同样，在这项研究中，EEM/PARAFAC 分析表明 25%的混合物不能提供饮用水质量，这表明这种简单、廉价的方法可用于饮用水再利用监测。
