Department of Civil Engineering, University of Asia Pacific, Dhaka 1205, Bangladesh.
Department of Civil Engineering, University of Asia Pacific, Dhaka 1205, Bangladesh.
Sci Total Environ. 2022 Sep 10;838(Pt 1):155942. doi: 10.1016/j.scitotenv.2022.155942. Epub 2022 May 14.
This study provides a comparative pollutant removal performance assessment between organic or construction materials-based four hybrid wetland systems that received landfill leachate. The hybrid systems included vertical flow (VF) followed by horizontal flow (HF)-based unplanted and planted systems, and planted electrodes incorporated microbial fuel cell (MFC) integrated hybrid wetlands systems. All the systems were run in free-draining mode. Overall mean chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) removal percentage of the hybrid systems ranged between 81 and 99%, 82 and 96%, 74 and 99%, respectively, under unstable input pollutant loading conditions. Additionally, up to 27% organic and up to 14% nitrogen removal improvement was observed in electrodes integrated free-draining VF wetlands. Free-draining and additional oxygen availability from atmospheric diffusion, rootzone improved the removal performance of MFC-based VF wetlands. Input load increment decreased organic, nutrient removals in second stage HF units due to saturated media. The chemical composition of the employed media supported biotic, abiotic organic, nutrient removal pathways. Nutrient accumulation percentage in plants tissue was very low, i.e., ≤3%. Bioenergy production across the MFC-based VF-HF wetlands decreased with input pollutant load increment. The single anode electrode-based VF wetland achieved maximum power density production, i.e., 294 mW/m.. The electrodes integrated hybrid systems achieved comparatively stable removal performance despite input pollutant/hydraulic load variation.
本研究对四种接收垃圾渗滤液的基于有机或建筑材料的混合湿地系统的污染物去除性能进行了比较评估。混合系统包括垂直流（VF）后接水平流（HF）的无植物和植物系统，以及结合微生物燃料电池（MFC）的植物电极集成混合湿地系统。所有系统均采用自由排水模式运行。在不稳定的输入污染物负荷条件下，混合系统的平均化学需氧量（COD）、总氮（TN）和总磷（TP）去除率分别在 81%至 99%、82%至 96%和 74%至 99%之间。此外，在自由排水的 VF 湿地中，电极集成还可提高 27%的有机物去除率和高达 14%的氮去除率。自由排水和大气扩散提供的额外氧气，根区改善了基于 MFC 的 VF 湿地的去除性能。由于介质饱和，输入负荷增加会降低第二阶段 HF 单元的有机物和养分去除率。所使用的介质的化学成分支持生物、非生物有机物和养分去除途径。植物组织中养分的积累百分比非常低，即≤3%。跨基于 MFC 的 VF-HF 湿地的生物能源产量随输入污染物负荷的增加而减少。基于单阳极电极的 VF 湿地实现了最大的功率密度生产，即 294 mW/m。尽管输入污染物/水力负荷发生变化，电极集成的混合系统仍能实现相对稳定的去除性能。
