Decezaro Samara Terezinha, Wolff Delmira B, Araújo Ronaldo K, Faccenda Henrique B, Perondi Taíse, Sezerino Pablo H
a Department of Sanitary and Environmental Engineering , Federal University of Santa Maria , Santa Maria , Brazil.
b Postgraduate Program in Civil and Environmental Engineering , University of Passo Fundo , Passo Fundo , Brazil.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2018;53(13):1131-1138. doi: 10.1080/10934529.2018.1530106. Epub 2018 Dec 30.
In order to investigate the potential of vertical flow constructed wetlands (VFCWs), a 24.5 m surface area filled with gravel and planted with Heliconia psittacorum, was implemented as an experimental system for domestic wastewater treatment in southern Brazil. The aims of the study were to (i) evaluate the performance of a full scale system septic tank (ST) and VFCW for decentralized domestic wastewater treatment, and (ii) identify the influence of Heliconia for hydraulic characteristics and consequent performance of the VFCW. The applied load rates in the VFCW were, on average, 10 g biochemical oxygen demand (BOD) m day, 4 g NH-N m day and a hydraulic loading rate (HLR) of 60 mm day. Physicochemical analyses of wastewater treatment were carried out through grab sample methodology, for 5 months. Additionally, hydrodynamic tests were performed during plant development using rhodamine. The study demonstrated the viability of the system for decentralized wastewater treatment in Brazil, with average removal efficiencies of 78% for chemical oxygen demand (COD) and 84% for total suspended solids (TSS), according to national effluent discharge regulations. In spite of media's large size, the VFCW achieved good average removal efficiencies. The tracer test results showed that the VFCW average hydraulic detention time increased as plants grew. This may have occurred due to interception of wastewater applied on the macrophyte's leaves as well as a reduction in filter media permeability caused by the spread of roots and rhizomes. These results indicate that the plants played an important role in increasing wastewater contact time in wetlands with high hydraulic conductivity such as a gravel VFCW.
为了研究垂直流人工湿地（VFCW）的潜力，在巴西南部建造了一个表面积为24.5平方米、填充砾石并种植了红鹤芋的实验系统，用于处理生活污水。该研究的目的是：（i）评估用于分散式生活污水处理的全尺寸化粪池（ST）和VFCW系统的性能；（ii）确定红鹤芋对VFCW水力特性及后续性能的影响。VFCW的平均应用负荷率为：生化需氧量（BOD）10克/（平方米·天）、氨氮4克/（平方米·天），水力负荷率（HLR）为60毫米/天。通过抓取采样法对污水处理进行了5个月的理化分析。此外，在植物生长期间使用罗丹明进行了水动力测试。根据国家污水排放规定，该研究证明了该系统在巴西用于分散式污水处理的可行性，化学需氧量（COD）的平均去除效率为78%，总悬浮固体（TSS）的平均去除效率为84%。尽管介质尺寸较大，但VFCW仍取得了良好的平均去除效率。示踪剂测试结果表明，随着植物生长，VFCW的平均水力停留时间增加。这可能是由于施加在大型植物叶片上的废水被截留，以及根系和根茎的蔓延导致过滤介质渗透性降低所致。这些结果表明，在具有高水力传导性的湿地（如砾石VFCW）中，植物在增加废水接触时间方面发挥了重要作用。
