Wünsch Robin, Mayer Carina, Plattner Julia, Eugster Fabienne, Wülser Richard, Gebhardt Jens, Hübner Uwe, Canonica Silvio, Wintgens Thomas, von Gunten Urs
FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Institute for Ecopreneurship, Hofackerstr. 30, 4132, Muttenz, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Institute for Ecopreneurship, Hofackerstr. 30, 4132, Muttenz, Switzerland; RWTH Aachen University, Aachener Verfahrenstechnik, Chemical Process Engineering, Forckenbeckstrasse 51, 52074, Aachen, Germany.
Water Res. 2021 May 1;195:116940. doi: 10.1016/j.watres.2021.116940. Epub 2021 Feb 18.
Organic micropollutants (MPs) are increasingly detected in water resources, which can be a concern for human health and the aquatic environment. Ultraviolet (UV) radiation based advanced oxidation processes (AOP) such as low-pressure mercury vapor arc lamp UV/HO can be applied to abate these MPs. During UV/HO treatment, MPs are abated primarily by photolysis and reactions with hydroxyl radicals (OH), which are produced in situ from HO photolysis. Here, a model is presented that calculates the applied UV fluence (H) and the OH exposure (CT) from the abatement of two selected MPs, which act as internal probe compounds. Quantification of the UV fluence and hydroxyl radical exposure was generally accurate when a UV susceptible and a UV resistant probe compound were selected, and both were abated at least by 50 %, e.g., iopamidol and 5-methyl-1H-benzotriazole. Based on these key parameters a model was developed to predict the abatement of other MPs. The prediction of abatement was verified in various waters (sand filtrates of rivers Rhine and Wiese, and a tertiary wastewater effluent) and at different scales (laboratory experiments, pilot plant). The accuracy to predict the abatement of other MPs was typically within ±20 % of the respective measured abatement. The model was further assessed for its ability to estimate unknown rate constants for direct photolysis (k) and reactions with OH (k). In most cases, the estimated rate constants agreed well with published values, considering the uncertainty of kinetic data determined in laboratory experiments. A sensitivity analysis revealed that in typical water treatment applications, the precision of kinetic parameters (k for UV susceptible and k for UV resistant probe compounds) have the strongest impact on the model's accuracy.
有机微污染物（MPs）在水资源中被越来越频繁地检测到，这可能会对人类健康和水生环境造成影响。基于紫外线（UV）辐射的高级氧化工艺（AOP），如低压汞蒸气弧光灯UV/HO，可用于去除这些微污染物。在UV/HO处理过程中，微污染物主要通过光解以及与羟基自由基（OH）反应而被去除，羟基自由基由HO光解原位产生。在此，提出了一个模型，该模型根据两种选定的用作内部探针化合物的微污染物的去除情况来计算施加的紫外线通量（H）和羟基自由基暴露量（CT）。当选择一种对紫外线敏感和一种对紫外线抗性的探针化合物，且两者的去除率至少达到50%时，例如碘帕醇和5-甲基-1H-苯并三唑，紫外线通量和羟基自由基暴露量的量化通常是准确的。基于这些关键参数，开发了一个模型来预测其他微污染物的去除情况。在各种水体（莱茵河和维泽河的砂滤水以及三级废水排放水）和不同规模（实验室实验、中试装置）下对去除情况的预测进行了验证。预测其他微污染物去除情况的准确性通常在各自测量去除率的±20%范围内。该模型还进一步评估了其估计直接光解（k）和与OH反应（k）的未知速率常数的能力。在大多数情况下，考虑到实验室实验中确定的动力学数据的不确定性，估计的速率常数与已发表的值吻合良好。敏感性分析表明，在典型的水处理应用中，动力学参数（对紫外线敏感的探针化合物的k和对紫外线抗性的探针化合物的k）的精度对模型的准确性影响最大。
