Department of Earth Sciences, University of Tabriz, 29 Bahman Blvd., Tabriz, Iran.
Department of Earth Sciences, University of Tabriz, 29 Bahman Blvd., Tabriz, Iran.
J Contam Hydrol. 2020 Mar;230:103604. doi: 10.1016/j.jconhyd.2020.103604. Epub 2020 Jan 21.
Adsorption is a well-known phenomenon that causes the remediation of BTEX (Benzene, Toluene, Ethylbenzene, and Xylene). Zeolite is typically useful for the removal of BTEX from groundwater. In this study, the migration of the BTEX plume was investigated in a bench-scale tank model as a shallow aquifer. The objective of this research was to analyze the performance of a natural zeolite in-situ PRB remediation technique. Natural zeolite was applied as a physical permeable reactive barrier. In the first part of the experiment, 40 ml of BTEX as a contaminant was injected at the injection point (BI) into the sand tank. Samples were taken periodically via 14 boreholes for BTEX test for 23 days and analyzed using a GC-FID instrument. The results indicated high removal rates of BTEX by passing through the zeolite barrier. Zeolite barrier reduced the BTEX concentration up to 90% of the initial value. However, the barrier efficiency started to decrease after 132 h since pollution injection reached a minimum amount (%53 of the initial value) due to occupying the free space and grain pore where BTEX was adsorbed onto the surface of zeolite, thereby decreasing the barrier efficiency.
吸附是一种众所周知的现象，会导致 BTEX（苯、甲苯、乙苯和二甲苯）的修复。沸石通常可用于去除地下水中的 BTEX。在这项研究中，作为浅层含水层，在台架规模的水箱模型中研究了 BTEX 羽流的迁移。本研究的目的是分析天然沸石原位 PRB 修复技术的性能。天然沸石被用作物理可渗透的反应性屏障。在实验的第一部分，将 40ml 的 BTEX 作为污染物注入到注水点（BI）的砂箱中。在 23 天内，通过 14 个钻孔定期取样进行 BTEX 测试，并使用 GC-FID 仪器进行分析。结果表明，BTEX 通过沸石屏障的去除率很高。沸石屏障将 BTEX 的浓度降低到初始值的 90%。然而，由于污染注入达到最小量（初始值的 53%），占据了自由空间和颗粒孔隙，BTEX 被吸附到沸石表面，从而降低了屏障效率，因此，在 132 小时后，屏障效率开始下降。
