State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Faculty of Agronomy, University of Lubumbashi, Democratic Republic of Congo.
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
Chemosphere. 2023 Jul;330:138703. doi: 10.1016/j.chemosphere.2023.138703. Epub 2023 Apr 24.
The use of natural agro-industrial materials as suspended fillers (SFs) in floating treatment wetlands (FTWs) to enhance nutrient removal performance has recently been gaining significant attention. However, the knowledge concerning the nutrient removal performance enhancement by different SFs (alone and in mixtures) and the major removal pathways is so far inadequate. The current research, for the first time, carried out a critical analysis using five different natural agro-industrial materials (biochar, zeolite, alum sludge, woodchip, flexible solid packing) as SFs in various FTWs of 20 L microcosm tanks, 450 L outdoor mesocosms, and a field-scale urban pond treating real wastewater over 180 d. The findings demonstrated that the incorporation of SFs in FTWs enhanced the removal performance of total nitrogen (TN) by 20-57% and total phosphorus (TP) by 23-63%. SFs further enhanced macrophyte growth and biomass production, leading to considerable increases in nutrient standing stocks. Although all the hybrid FTWs showed acceptable treatment performances, FTWs set up with mixtures of all five SFs significantly enhanced biofilm formation and enriched the abundances of the microbial community related to nitrification and denitrification processes, supporting the detected excellent N retention. N mass balance assessment demonstrated that nitrification-denitrification was the major N removal pathway in reinforced FTWs, and the high removal efficiency of TP was attributable to the incorporation of SFs into the FTWs. Nutrient removal efficiencies ranked in the following order among the various trials: microcosm scale (TN: 99.3% and TP: 98.4%) > mesocosm scale (TN: 84.0% and TP: 95.0%) > field scale (TN: -15.0-73.7% and TP: -31.5-77.1%). These findings demonstrate that hybrid FTWs could be easily scaled up for the removal of pollutants from eutrophic freshwater systems over the medium term in an environmentally-friendly way in regions with similar environmental conditions. Moreover, it demonstrates hybrid FTW as a novel way of disposing of significant quantities of wastes, showing a win-win means with a huge potential for large-scale application.
利用天然农业工业材料作为悬浮填料（SFs）在浮式处理湿地（FTWs）中增强养分去除性能，近来受到了广泛关注。然而，目前对于不同 SFs（单独和混合）增强养分去除性能的知识以及主要去除途径还不够充分。本研究首次使用五种不同的天然农业工业材料（生物炭、沸石、铝污泥、木屑、柔性固体填料）作为 SFs，在 20 L 微宇宙罐、450 L 户外中观模型和野外规模城市池塘的各种 FTWs 中进行了关键分析，处理实际废水超过 180 天。研究结果表明，在 FTWs 中添加 SFs 可将总氮（TN）去除率提高 20-57%，总磷（TP）去除率提高 23-63%。SFs 进一步促进了水生植物的生长和生物量的产生，导致养分储存量的显著增加。尽管所有混合 FTWs 都表现出可接受的处理性能，但使用所有五种 SFs 混合物建立的 FTWs 显著增强了生物膜的形成，并丰富了与硝化和反硝化过程相关的微生物群落的丰度，支持了检测到的优异的氮保留。氮质量平衡评估表明，硝化-反硝化是强化 FTWs 中主要的氮去除途径，而高的 TP 去除效率归因于 SFs 被纳入 FTWs。在各种试验中，养分去除效率的顺序如下：微宇宙规模（TN：99.3%和 TP：98.4%）>中观模型规模（TN：84.0%和 TP：95.0%）>野外规模（TN：-15.0-73.7%和 TP：-31.5-77.1%）。这些发现表明，混合 FTWs 可以很容易地从中短期在具有类似环境条件的地区以环保的方式从富营养化淡水中去除污染物。此外，它还展示了混合 FTW 是一种处理大量废物的新方法，是一种具有巨大应用潜力的双赢手段。
