Department of Civil and Materials Engineering, University of Illinois at Chicago, 842 West Taylor Street, Chicago, IL, 60607, USA.
Department of Chemical Engineering, BiotecnIA, University of Vigo, Rua Maxwell s/n, Building Funcion, 36310, Vigo, Spain.
Environ Sci Pollut Res Int. 2021 Feb;28(6):7574-7585. doi: 10.1007/s11356-020-11120-4. Epub 2020 Oct 9.
Beach closings are a growing concern in coastal regions because of serious public health and economic ramifications due to the presence of pollutants in stormwater runoff. An underground permeable filter system is proposed to treat such stormwater pollution. Selection of filter media that can treat multiple contaminants in stormwater runoff has been a challenging task. This paper investigates the effectiveness of mixed or layered filter media for the removal of mixed contaminants (nutrient and heavy metal) from synthetic stormwater. Sorption experiments were used to assess the ability of the combination of various materials (calcite, zeolite, sand, and iron filings) to remove nutrients and heavy metals. Based on the results of individual removal efficiency, four sets of combinations of media mixtures were prepared: three mixed media conditions and one layered media condition. Mixed media-1, containing higher ratio of calcite, zeolite, and iron filings, was found to achieve the highest removal efficiency of nitrate (96%), Cr (~ 99%), and Cu (~ 99%). Mixed media-2 removed Zn significantly with a removal efficiency higher than 99% due to the sorption capacity of iron filings and both mixed media-2 and 3 showed efficient removal of Ni (~ 94%) in effluent. Layered media was found to be most efficient in Cd removal (~ 99%). All mixture of materials showed more than 99% removal of total phosphorus and Pb. The sorption efficiency of the different mixtures showed that a combination of traditional (sand) and alternative materials (calcite, zeolite, and iron filings) can be used as an effective medium for the treatment of nutrient and heavy metal contaminants commonly found in stormwater.
由于雨水径流中的污染物对沿海地区的公共健康和经济造成严重影响，海滩关闭的情况日益受到关注。目前提出了一种地下渗透过滤系统来处理这种雨水污染。选择可以处理雨水径流中多种污染物的过滤介质一直是一项具有挑战性的任务。本文研究了混合或分层过滤介质在去除合成雨水中混合污染物（营养物和重金属）方面的有效性。采用吸附实验来评估各种材料（方解石、沸石、沙子和铁粉）的组合去除营养物和重金属的能力。根据个体去除效率的结果，制备了四组介质混合物的组合：三种混合介质条件和一种分层介质条件。混合介质-1 含有更高比例的方解石、沸石和铁粉，对硝酸盐（96%）、Cr（99%）和 Cu（99%）的去除效率最高。由于铁粉的吸附能力，混合介质-2 显著去除了 Zn，去除效率高于 99%，且混合介质-2 和 3 对 Ni（94%）的去除效率也很高。分层介质对 Cd 的去除效率最高（99%）。所有混合物对总磷和 Pb 的去除率均超过 99%。不同混合物的吸附效率表明，传统（沙子）和替代材料（方解石、沸石和铁粉）的组合可作为处理雨水中常见营养物和重金属污染物的有效介质。
