Buffle Marc-Olivier, Schumacher Jochen, Salhi Elisabeth, Jekel Martin, von Gunten Urs
Department of Water Resources and Drinking Water, Swiss Federal Institute for Environmental Science and Technology (eawag), Switzerland.
Water Res. 2006 May;40(9):1884-94. doi: 10.1016/j.watres.2006.02.026. Epub 2006 Apr 19.
Due to a lack of adequate experimental techniques, the kinetics of the first 20s of ozone decomposition in natural water and wastewater is still poorly understood. Introducing a continuous quench-flow system (CQFS), measurements starting 350 ms after ozone addition are presented for the first time. Very high HO. to O3 exposures ratios (Rct=integralHO.dt/integralO3dt) reveal that the first 20s of ozonation present oxidation conditions that are similar to ozone-based advanced oxidation processes (AOP). The oxidation of carbamazepine could be accurately modeled using O3 and HO. exposures measured with CQFS during wastewater ozonation. These results demonstrate the applicability of bench scale determined second-order rate constants for wastewater ozonation. Important degrees of pharmaceutical oxidation and microbial inactivation are predicted, indicating that a significant oxidation potential is available during wastewater ozonation, even when ozone is entirely decomposed in the first 20s.
由于缺乏足够的实验技术，天然水和废水中臭氧分解最初20秒的动力学仍未得到充分理解。引入连续淬灭流动系统（CQFS）后，首次给出了添加臭氧350毫秒后开始的测量结果。非常高的羟基自由基与臭氧暴露比（Rct = ∫[羟基自由基]dt / ∫[臭氧]dt）表明，臭氧化最初的20秒呈现出与基于臭氧的高级氧化过程（AOP）相似的氧化条件。在废水臭氧化过程中，使用CQFS测量的臭氧和羟基自由基暴露量，可以准确模拟卡马西平的氧化过程。这些结果证明了实验室规模测定的二级反应速率常数在废水臭氧化中的适用性。预测了药物氧化和微生物失活的重要程度，表明即使臭氧在最初20秒内完全分解，废水臭氧化过程中仍具有显著的氧化潜力。
