IMDEA Water Institute, Avda Punto Com, 2, 28805, Alcalá de Henares, Madrid, Spain.
IMDEA Water Institute, Avda Punto Com, 2, 28805, Alcalá de Henares, Madrid, Spain.
J Environ Manage. 2020 May 1;261:110255. doi: 10.1016/j.jenvman.2020.110255. Epub 2020 Mar 2.
Vegetation Filters (VFs) can be a sustainable solution to treat wastewater and to recover resources such as nutrients, water and biomass from small municipalities and isolated dwellings. However, under certain conditions, the leakage of nutrients, especially of nitrate, can represent a limitation. The addition of two sustainable soil amendments, woodchips and biochar, has been tested as a strategy to improve nutrient attenuation in VFs increasing sorption sites and microbial activity. To this end, unsaturated infiltration and batch experiments have been carried out at laboratory scale. The systems for infiltration experiments contain natural soil, natural soil amended with woodchips and natural soil amended with biochar. To determine the sorption capacity of NH, batch tests were performed using an amendment/SWW ratio of 1:20 and an NH initial concentration ranging from 30 to 600 mg L. Results from the infiltration experiments show a high attenuation (~95%) of total phosphorous (TP) independently of the amendments. Different behaviour is observed for total nitrogen (TN). The removal of this species is obtained only in the soil amended with woodchips (>85%) whereas the natural soil alone and the soil with biochar have no impact on TN attenuation. In these two porous media, all the NH input concentration is transformed to NO that infiltrates without further reactions. According to batch experiment results, the potential role of biochar in the nutrient attenuation is limited to sorption processes (K (NH) = 21.37-193.18 L kg). Woodchips act primarily as a labile source of carbon promoting biodegradation, being more effective for nutrient attenuation than the sorption capacity of biochar.
植被过滤器 (VF) 可以成为处理废水和从小型市政和孤立住宅中回收营养物质、水和生物质等资源的可持续解决方案。然而，在某些条件下，营养物质（尤其是硝酸盐）的泄漏可能会受到限制。已经测试了添加两种可持续的土壤改良剂——木屑和生物炭——作为提高 VF 中营养物质衰减的策略，增加吸附位点和微生物活性。为此，在实验室规模上进行了非饱和渗滤和批量实验。渗滤实验系统包含天然土壤、添加木屑的天然土壤和添加生物炭的天然土壤。为了确定 NH 的吸附能力，使用 1:20 的改良剂/SWW 比和 30 至 600 mg L 的初始 NH 浓度进行了批量测试。渗滤实验结果表明，总磷 (TP) 的衰减率很高（~95%），与改良剂无关。总氮 (TN) 的行为则不同。只有在添加木屑的土壤中才能去除这种物质（>85%），而单独的天然土壤和添加生物炭的土壤对 TN 衰减没有影响。在这两种多孔介质中，所有输入的 NH 浓度都转化为 NO，没有进一步的反应就渗透下去了。根据批量实验结果，生物炭在营养物质衰减中的潜在作用仅限于吸附过程（K(NH) = 21.37-193.18 L kg）。木屑主要作为一种易生物降解的碳源起作用，对营养物质衰减的效果比生物炭的吸附能力更有效。
