Environment and Water Resources by the Federal University of Minas Gerais, Brazil.
Water Sci Technol. 2013;67(6):1345-52. doi: 10.2166/wst.2013.008.
This study aimed to evaluate the behaviour of two horizontal subsurface flow constructed wetland units regarding solids build up and clogging of the filter medium. In order to analyse the causes of this process, which is considered the major operational problem of constructed wetlands, studies were carried out to characterize accumulated solids and hydraulic conductivity at specific points of the beds of two wetlands (planted with Typha latifolia and unplanted units) receiving effluent from an upflow anaerobic sludge blanket reactor treating sanitary sewage (population equivalent of 50 inhabitants each unit). The experiments were performed after the units were operating for 2 years and 4 months. This study presents comparative results related to the quantification and characterization of accumulated solids and hydraulic conductivity along the length and width of the filter beds. Approximately 80% of the solids found were inorganic (fixed). Near the inlet end, the rate interstitial solids/attached solids was 5.0, while in the outlet end it was reduced to 1.5. Hydraulic conductivity was lower near the inlet of the units (as expected) and, by comparing the planted wetland with the unplanted, the hydraulic conductivity was lower in the former, resulting in larger undesired surface flow.
本研究旨在评估两个水平潜流人工湿地单元的行为，以了解固体物质的积累和过滤介质的堵塞情况。为了分析这一过程的原因，这被认为是人工湿地的主要运行问题，本研究对从处理生活污水的上流式厌氧污泥床反应器（每个单元的人口当量为 50 人）中流出的废水进行处理的两个湿地（种植了芦苇和未种植的单元）的床层中特定点的累积固体和水力传导率进行了研究。这些实验是在单元运行了 2 年零 4 个月后进行的。本研究提供了与沿过滤床长度和宽度量化和表征累积固体和水力传导率相关的比较结果。发现的固体物质中约有 80%是无机的（固定的）。在进口端附近，间隙固体/附着固体的速率为 5.0，而在出口端则降低到 1.5。正如预期的那样，单元的进口附近的水力传导率较低，并且通过比较种植湿地和未种植湿地，前者的水力传导率较低，导致更大的不期望的表面流。
