a Department of Environmental Engineering and Water Technology , UNESCO-IHE, Institute for Water Education , Delft , The Netherlands.
b Department of Agricultural and Bio-resources Engineering , Federal University of Technology , Minna , Nigeria.
Int J Phytoremediation. 2018 Jan 2;20(1):44-53. doi: 10.1080/15226514.2017.1337062.
This study examined the performance of pilot-scale vertical subsurface flow constructed wetlands (VSF-CWs) planted with three indigenous plants, i.e. Typha latifolia, Cyperus alternifolius, and Cynodon dactylon, in removing heavy metals from secondary treated refinery wastewater under tropical conditions. The T. latifolia-planted VSF-CW had the best heavy metal removal performance, followed by the Cyperus alternifolius-planted VSF-CW and then the Cynodon dactylon-planted VSF-CW. The data indicated that Cu, Cr, Zn, Pb, Cd, and Fe were accumulated in the plants at all the three VSF-CWs. However, the accumulation of the heavy metals in the plants accounted for only a rather small fraction (0.09-16%) of the overall heavy metal removal by the wetlands. The plant roots accumulated the highest amount of heavy metals, followed by the leaves, and then the stem. Cr and Fe were mainly retained in the roots of T. latifolia, Cyperus alternifolius, and Cynodon dactylon (TF < 1), meaning that Cr and Fe were only partially transported to the leaves of these plants. This study showed that VSF-CWs planted with T. latifolia, Cyperus Alternifolius, and Cynodon dactylon can be used for the large-scale removal of heavy metals from secondary refinery wastewater.
本研究考察了在热带条件下，三种本土植物（香蒲、水葱和狗牙根）种植于中试规模的垂直潜流人工湿地（VSF-CWs）中去除二级处理炼油废水中重金属的性能。种植香蒲的 VSF-CW 对重金属的去除效果最好，其次是种植水葱的 VSF-CW，然后是种植狗牙根的 VSF-CW。数据表明，Cu、Cr、Zn、Pb、Cd 和 Fe 都在所有三种 VSF-CWs 的植物中积累。然而，重金属在植物中的积累仅占湿地整体重金属去除量的一小部分（0.09-16%）。植物根系积累的重金属最多，其次是叶片，然后是茎。Cr 和 Fe 主要保留在香蒲、水葱和狗牙根的根系中（TF < 1），这意味着 Cr 和 Fe 仅部分被运输到这些植物的叶片中。本研究表明，种植香蒲、水葱和狗牙根的 VSF-CWs 可用于大规模去除二级炼油废水中的重金属。
