Photolysis of free chlorine to hydroxyl radical by sunlight and ultraviolet irradiation for enhanced disinfection of chlorine-resistant waterborne pathogens

阳光和紫外线照射将游离氯光解为羟基自由基，增强耐氯水生病原体的消毒

• 批准号: 1236303
• 负责人: Michael Dodd
• 金额: $ 35.41万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1236303&HistoricalAwards=false
• 关键词: Photolysis; free; chlorine; hydroxyl; radical

1236303DoddFree available chlorine (FAC) remains the most widely used disinfectant in drinking water practice worldwide. It is cheap, easily utilized as a disinfectant, portable, and in general highly effective for achieving the inactivation of a wide variety of waterborne microbial pathogens. However, it is known to be relatively ineffective as a primary disinfectant of such important pathogenic agents as Cryptosporidium parvum, Mycobacterium avium, and Giardia lamblia, This has led to widespread adoption of more effective, but often substantially more capital-, equipment-, and energy-intensive alternative disinfectants such as UV light and ozone. Recent findings suggest that inactivation of chlorine-recalcitrant microbial pathogens may actually be achievable at considerably lower expense by utilizing sunlight or monochromatic UV light to photolyze FAC to such highly-reactive oxidant species as hydroxyl radical, atomic oxygen, and ozone during conventional chlorination. In such an approach, FAC and photochemically-generated oxidants may act in tandem to yield substantially greater inactivation of various waterborne pathogens than would be achievable using chlorine alone. This investigation will utilize a combination of chemical and microbiological tools to quantify inactivation of chlorine-resistant viral, bacterial, and protozoan pathogens during conventional chlorination processes enhanced by FAC photolysis. The primary objective of this work will be to evaluate the use of sunlight for photochemical enhancement of chlorination processes. However, the investigation will also focus on potential applications of monochromatic and polychromatic UV light sources, on account of their growing frequency of application in drinking water treatment. The project team will develop and optimize experimental and analytical procedures for quantifying pathogen inactivation during photochemically-enhanced chlorination by first utilizing two common surrogates for waterborne pathogens B. subtilis spores and MS2 bacteriophage, followed by the chlorine-resistant human pathogens M. avium, Coxsackievirus B5 (CVB5), and C. parvum. These procedures will subsequently be utilized to examine the influence of such critical parameters as pH, water temperature, alkalinity, and matrix oxidant demand on inactivation efficiency for each pathogen under simulated sunlight, natural sunlight, and various artificial UV light sources in buffered laboratory reagent water systems, as well as in real water matrixes acquired from municipal water utilities in the Puget Sound region. Particular emphasis will be placed on development of kinetic models for pathogen inactivation that take into account measured water quality parameters and spectral irradiance data. Finally, formation potentials of organic and inorganic DBPs likely to be generated during application of photochemically-enhanced chlorination (e.g., trihalomethanes, haloacetic acids, ClO3-, ClO4-, and BrO3-) will be quantified under a variety of scenarios relevant to full-scale application. In addition to establishing a theoretical framework for modeling chlorine-resistant pathogen inactivation during photochemically-enhanced chlorination, this project will provide an extensive dataset for M. avium, CVB5, and C. parvum inactivation under a wide variety of conditions applicable to full-scale water treatment (including variable irradiation wavelength, intensity, temperature, pH, and alkalinity). This research could support the photochemical augmentation of conventional drinking water chlorination processes at full-scale, with minimal equipment and process retrofit. Application of such an approach could have substantial benefits over existing alternatives to chlorine-based disinfection processes. First, chlorination is used in the vast majority of water treatment facilities. Second, utilization of solar radiation in particular as a light source could net significant cost and energy savings in comparison to processes utilizing ozone or artificial UV light. In addition, if a UV process is already in place at a facility, that process could quite easily be adapted for photochemically-enhanced chlorination simply by dosing FAC upstream of the UV reactor(s). Furthermore, sunlight-enhanced chlorination could prove exceptionally useful for ensuring disinfection of chlorine-resistant pathogens during point-of-use applications in developed and developing societies, on account of its expected low costs and ease of implementation.

1236303Doddfree可用的氯（FAC）仍然是全球饮用水实践中使用最广泛的消毒剂。它很便宜，很容易用作消毒剂，便携式，并且通常可以非常有效地实现多种水性微生物病原体的失活。然而，众所周知，它是对重要的致病剂的主要消毒剂，例如隐孢子虫，矮杆菌和贾迪亚·兰布利亚（Giardia lamblia），这导致广泛采用更有效的，但通常更有效的，但通常更有效的资本，设备，设备，能量，替代性的消毒剂和诸如uv light和oz sight和oz。最近的发现表明，通过利用阳光或单色紫外线光将氧化氧化物质（如羟基自由基，原子质氧气和常规氯化过程中的臭氧）等高度反应性氧化物种，可以通过使用阳光或单色紫外线将其灭活以大大降低费用来实现。在这种方法中，FAC和光化学生成的氧化剂可以同时起作用，从而比单独使用氯可以实现各种水传播病原体的灭活量要大得多。这项研究将利用化学和微生物工具的组合来量化耐氯，细菌和原生动物病原体在传统的氯化过程中通过FAC光溶解增强的过程。这项工作的主要目的是评估阳光用于光化学增强氯化过程的使用。但是，由于它们在饮用水处理中的应用频率不断增长，该研究还将集中于单色和多色紫外线光源的潜在应用。该项目团队将通过首先利用两种常见的替代物来制定并优化实验和分析程序，以量化光化性增强氯化过程中的病原体失活。 These procedures will subsequently be utilized to examine the influence of such critical parameters as pH, water temperature, alkalinity, and matrix oxidant demand on inactivation efficiency for each pathogen under simulated sunlight, natural sunlight, and various artificial UV light sources in buffered laboratory reagent water systems, as well as in real water matrixes acquired from municipal water utilities in the Puget Sound region.将特别重点放在病原体失活的动力学模型上，这些模型考虑了测得的水质参数和光谱辐照度数据。最后，在施用光化学增强氯化过程中可能产生的有机和无机DBP的形成电位（例如，在与全尺度应用相关的各种场景下，将对各种风景进行量化，将在各种风景中进行量化。除了建立一个理论框架，用于在光化学增强的氯化过程中建模耐氯的病原体灭活外，该项目还将为M. avium，CVB5和C. parvum C. parvum灭活提供广泛的数据集。这项研究可以支持全面的传统饮用水氯化过程的光化学增强，并具有最少的设备和过程改造。这种方法的应用可能比现有的基于氯的消毒过程的替代方案具有重大好处。首先，在绝大多数水处理设施中使用氯化。其次，与利用臭氧或人造紫外线的过程相比，与太阳辐射的利用尤其是光源可以净化大量成本和节能。此外，如果设施中的紫外线工艺已经存在，那么仅通过紫外反应堆上游的给药fac（S），即可很容易地适应光化学增强的氯化。此外，由于其预期的低成本和易于实施，阳光增强的氯化可能对确保在发达和发展中的使用点应用中对耐氯的病原体进行消毒非常有用。

项目成果

Characterization of disinfection byproduct formation and associated changes to dissolved organic matter during solar photolysis of free available chlorine

游离有效氯的太阳光解过程中消毒副产物形成和溶解有机物相关变化的表征

• DOI: 10.1016/j.watres.2018.09.022
• 发表时间: 2018
• 期刊: Water Research
• 影响因子: 12.8
• 作者: Tessora R Young;Wentao Li;Alan Guo;Gregory V Korshin;Michael C Dodd
• 通讯作者: Michael C Dodd

Enhanced Inactivation of Bacillus subtilis Spores during Solar Photolysis of Free Available Chlorine

• DOI: 10.1021/es401906x
• 发表时间: 2013-11-19
• 期刊: ENVIRONMENTAL SCIENCE & TECHNOLOGY
• 影响因子: 11.4
• 作者: Forsyth, Jenna E.;Zhou, Peiran;Dodd, Michael C.
• 通讯作者: Dodd, Michael C.

Enhanced Inactivation of Cryptosporidium parvum Oocysts during Solar Photolysis of Free Available Chlorine

• DOI: 10.1021/ez500270u
• 发表时间: 2014-10
• 期刊: Environmental Science and Technology Letters
• 影响因子: 10.9
• 作者: Peiran Zhou;G. Giovanni;J. Meschke;Michael C. Dodd

Rapid determination of trace haloacetic acids in water and wastewater using non-suppressed ion chromatography with electrospray ionization-tandem mass spectrometry

使用非抑制离子色谱电喷雾电离串联质谱快速测定水和废水中的痕量卤乙酸

• DOI: 10.1016/j.scitotenv.2020.142297
• 发表时间: 2021-02-01
• 期刊: SCIENCE OF THE TOTAL ENVIRONMENT
• 影响因子: 9.8
• 作者: Cheng, Shi;Wu, Ya-Ping;Li, Ai-Min
• 通讯作者: Li, Ai-Min