Henderson R K, Baker A, Murphy K R, Hambly A, Stuetz R M, Khan S J
UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
Water Res. 2009 Mar;43(4):863-81. doi: 10.1016/j.watres.2008.11.027. Epub 2008 Dec 3.
A rapid, highly sensitive and selective detector is urgently required to detect contamination events in recycled water systems - for example, cross-connection events in dual reticulation pipes that recycle advanced treated sewage effluent - as existing technologies, including total organic carbon and conductivity monitoring, cannot always provide the sensitivity required. Fluorescence spectroscopy has been suggested as a potential monitoring tool given its high sensitivity and selectivity. A review of recent literature demonstrates that by monitoring the fluorescence of dissolved organic matter (DOM), the ratios of humic-like (Peak C) and protein-like (Peak T) fluorescence peaks can be used to identify trace sewage contamination in river waters and estuaries, a situation analogous to contamination detection in recycled water systems. Additionally, strong correlations have been shown between Peak T and biochemical oxygen demand (BOD) in rivers, which is indicative of water impacted by microbial activity and therefore of sewage impacted systems. Hence, this review concludes that the sensitive detection of contamination events in recycled water systems may be achieved by monitoring Peak T and/or Peak C fluorescence. However, in such systems, effluent is treated to a high standard resulting in much lower DOM concentrations and the impact of these advanced treatment processes on Peaks T and C fluorescence is largely unknown and requires investigation. This review has highlighted that further work is also required to determine (a) the stability and distinctiveness of recycled water fluorescence in relation to the treatment processes utilised, (b) the impact of matrix effects, particularly the impact of oxidation, (c) calibration issues for online monitoring, and (d) the advanced data analytical techniques required, if any, to improve detection of contamination events.
迫切需要一种快速、高灵敏度和高选择性的探测器来检测再生水系统中的污染事件——例如，回收深度处理污水的双管网中的交叉连接事件——因为包括总有机碳和电导率监测在内的现有技术并不总能提供所需的灵敏度。鉴于荧光光谱法具有高灵敏度和高选择性，已被建议作为一种潜在的监测工具。对近期文献的综述表明，通过监测溶解有机物（DOM）的荧光，类腐殖质（峰C）和类蛋白质（峰T）荧光峰的比率可用于识别河水和河口的微量污水污染，这与再生水系统中的污染检测情况类似。此外，河流中峰T与生化需氧量（BOD）之间已显示出强相关性，这表明水受到微生物活动的影响，因此也受到污水影响系统的影响。因此，本综述得出结论，通过监测峰T和/或峰C荧光，可以实现对再生水系统中污染事件的灵敏检测。然而，在这样的系统中，出水经过高标准处理，导致DOM浓度低得多，而这些深度处理工艺对峰T和峰C荧光的影响在很大程度上未知，需要进行研究。本综述强调，还需要进一步开展工作，以确定：（a）再生水荧光相对于所采用处理工艺的稳定性和独特性；（b）基质效应的影响，特别是氧化的影响；（c）在线监测的校准问题；以及（d）若需要，为改进污染事件检测所需的先进数据分析技术。
