U.S. Environmental Protection Agency, ORD/CEMM Atlantic Coastal Environmental Sciences Division, 27 Tarzwell Drive, Narragansett, RI 02882, USA; University of Rhode Island, Department of Geosciences, 9 E Alumni Avenue, Kingston, RI 02881, USA.
Enchem Engineering, 151 California Street, Newton, MA 02458, USA.
J Contam Hydrol. 2022 Feb;245:103937. doi: 10.1016/j.jconhyd.2021.103937. Epub 2021 Dec 7.
The research presented herein investigates a peroxone activated persulfate (PAP) oxidant, commercialized under the trade name OxyZone®, and its effects on 1,4-Dioxane (dioxane) contaminated water under column scale conditions in the presence of porous material. There is a limited understanding of the underlying processes that govern PAP oxidation, including the oxidation rates in the presence of aquifer material, and how these reactions proceed once the oxidant is injected into a contaminant plume. Initial batch experiments with porous material (e.g. sand) provided data on the reaction rates of dioxane oxidation as a function of the oxidant: contaminant ratio. The observed degradation rates were approximately 4 times lower than those reported for aqueous solutions containing no porous media. Subsequent column experiments simulated two PAP injections schemes along the flowpath of a dioxane plume to study if the injection of one oxidant slug may yield different results than injecting the same oxidant volume at two separate locations. The injection of one oxidant slug was found more effective, resulting in near complete destruction of dioxane over a prolonged time at a rate more than an order of magnitude greater than in the two-slug injection scenario. Tracer test results suggest that the prolonged oxidant reactivity was in part caused by the high density of the injected oxidant solution. Overall, the results underline the importance of accounting for the properties of both the oxidant solution and the porous material when considering the injection of PAP oxidant into an impacted aquifer.
本文研究了一种过一硫酸氢盐（PAP）氧化剂，以商品名 OxyZone®销售，并在多孔材料存在的情况下，在柱规模条件下研究其对 1,4-二恶烷（二恶烷）污染水的影响。对于控制 PAP 氧化的基本过程，包括含水层材料存在时的氧化速率以及一旦氧化剂注入污染物羽流时这些反应如何进行，人们的了解有限。初步的多孔材料（例如砂）批处理实验提供了氧化剂量与污染物比作为函数的二恶烷氧化反应速率的数据。观察到的降解速率比不含多孔介质的水溶液中报道的降解速率低约 4 倍。随后的柱实验模拟了沿二恶烷羽流的两条 PAP 注入方案，以研究在两个不同位置注入相同氧化剂体积与注入一个氧化剂弹丸是否会产生不同的结果。结果发现，注入一个氧化剂弹丸更有效，在长时间内以比两弹丸注入方案高一个数量级的速度几乎完全破坏了二恶烷。示踪剂测试结果表明，延长的氧化剂反应性部分是由于注入氧化剂溶液的高密度所致。总体而言，这些结果强调了在考虑将 PAP 氧化剂注入受影响的含水层时，必须考虑氧化剂溶液和多孔材料特性的重要性。
