Advanced oxidation and disinfection using ultraviolet light

该提案将分为两部分：(1)开发在线影响（紫外线剂量）测量系统-我们发现氯类（次氯酸和次氯酸盐离子）在水中254 nm处的紫外线光解具有高量子产率（接近1.0）。事实上，在某些情况下，在溶解有机物存在的情况下，量子产率会大得多。这种光化学反应的一些方面仍需要确定，例如对产物和中间体的详细检查，以及使用中压紫外线灯（多色紫外线输出）与低压灯（254 nm单色）的效果。我们建议在下一个拨款期内研究这些方面。本资助期的研究表明，水溶液中氯的光解作用发生在紫外线消毒范围内的影响（紫外线剂量）。拟议的工作将推动这一实际方案，可用于提供紫外线消毒反应器的在线监测。我们还将探索使用氯光解系统作为一种“高级氧化”过程来减少污染。(2)紫外线空气处理-事实证明，利用紫外线对气流进行消毒，对建筑物空气系统、医院手术室和康复室以及家庭空气循环系统中的空气进行处理非常有吸引力。遗憾的是，目前没有有关紫外线空气消毒系统认证的规定，也没有任何确定紫外线空气消毒系统所产生的影响（紫外线剂量）的方案。我们与加拿大埃德蒙顿Seacor Environmental公司的W. B. Kindzierski博士合作，建议制定一项生物剂量学实验方案，旨在确定紫外线空气消毒系统所产生的影响（紫外线剂量）。我们将设置一个装有UV灯的实验风道，可以仔细控制和测量空气流速和UV灯功率。

The Proposal will be in two parts: (1) Development of an online fluence (UV dose) measurement system - We have found that the ultraviolet (UV) photolysis of chlorine species (hypochlorous acid and hypochlorite ion) at 254 nm in water has a high quantum yield (near 1.0). Indeed, under certain circumstances, the quantum yield can be much larger in the presence of dissolved organic matter. There are some aspects of this photochemical reaction that still need to be determined, such as a detailed examination of the products and intermediates and the effect of using a medium pressure UV lamp (polychromatic UV output) as opposed to a low pressure lamp (monochromatic at 254 nm). We propose to examine these aspects in the next grant period. Research in the current grant period has shown that the photolysis of chlorine species in aqueous solution occurs at fluences (UV doses) in the range of UV disinfection. The proposed work will carry this forward to a practical protocol that can be used to provide online monitoring of UV disinfection reactors. We will also explore the use of the chlorine photolysis system as an "Advanced Oxidation" process for pollution abatement. (2) UV Air Treatment - The disinfection of air streams using ultraviolet (UV) light is proving to be very attractive for the treatment of air in building air systems, hospital operation and recovery rooms and home air circulation systems. Unfortunately, there are at present no regulations concerning the certification of UV air disinfection systems nor any protocols for the determination of the fluence (UV dose) delivered by a UV air disinfection system. In collaboration with Dr. W. B. Kindzierski at Seacor Environmental in Edmonton AB, we propose to develop a protocol for biodosimetry experiments aimed at determining the fluence (UV dose) delivered by a UV air disinfection system. We will set up an experimental air duct containing UV lamp(s), where the air flow rate and UV lamp power can be carefully controlled and measured.