Valhondo Cristina, Carrera Jesús, Ayora Carlos, Barbieri Manuela, Nödler Karsten, Licha Tobias, Huerta Maria
GHS Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18-26, 08034, Barcelona, Spain,
Environ Sci Pollut Res Int. 2014 Oct;21(20):11832-43. doi: 10.1007/s11356-014-2834-7. Epub 2014 May 6.
Artificial recharge improves several water quality parameters, but has only minor effects on recalcitrant pollutants. To improve the removal of these pollutants, we added a reactive barrier at the bottom of an infiltration basin. This barrier contained aquifer sand, vegetable compost, and clay and was covered with iron oxide dust. The goal of the compost was to sorb neutral compounds and release dissolved organic carbon. The release of dissolved organic carbon should generate a broad range of redox conditions to promote the transformation of emerging trace organic contaminants (EOCs). Iron oxides and clay increase the range of sorption site types. In the present study, we examined the effectiveness of this barrier by analyzing the fate of nine EOCs. Water quality was monitored before and after constructing the reactive barrier. Installation of the reactive barrier led to nitrate-, iron-, and manganese-reducing conditions in the unsaturated zone below the basin and within the first few meters of the saturated zone. Thus, the behavior of most EOCs changed after installing the reactive barrier. The reactive barrier enhanced the removal of some EOCs, either markedly (sulfamethoxazole, caffeine, benzoylecgonine) or slightly (trimethoprim) and decreased the removal rates of compounds that are easily degradable under aerobic conditions (ibuprofen, paracetamol). The barrier had no remarkable effect on 1H-benzotriazole and tolyltriazole.
人工回灌改善了几个水质参数，但对难降解污染物的影响较小。为了提高这些污染物的去除率，我们在渗滤池底部添加了一个反应屏障。该屏障包含含水层砂、蔬菜堆肥和粘土，并覆盖有氧化铁粉尘。堆肥的目的是吸附中性化合物并释放溶解有机碳。溶解有机碳的释放应产生广泛的氧化还原条件，以促进新兴微量有机污染物（EOCs）的转化。氧化铁和粘土增加了吸附位点类型的范围。在本研究中，我们通过分析9种EOCs的归宿来检验该屏障的有效性。在建造反应屏障前后对水质进行了监测。反应屏障的安装导致渗滤池下方非饱和带以及饱和带最初几米内出现硝酸盐、铁和锰还原条件。因此，安装反应屏障后，大多数EOCs的行为发生了变化。反应屏障提高了一些EOCs的去除率，要么显著提高（磺胺甲恶唑、咖啡因、苯甲酰芽子碱），要么略有提高（甲氧苄啶），并降低了在有氧条件下易降解化合物（布洛芬、对乙酰氨基酚）的去除率。该屏障对1H-苯并三唑和甲苯基三唑没有显著影响。
