Mayes W M, Batty L C, Younger P L, Jarvis A P, Kõiv M, Vohla C, Mander U
Hydrogeochemical Engineering Research and Outreach group, Sir Joseph Swan Institute for Energy Research, Newcastle University, Newcastle upon Tyne, UK.
Sci Total Environ. 2009 Jun 15;407(13):3944-57. doi: 10.1016/j.scitotenv.2008.06.045. Epub 2008 Aug 15.
Constructed wetlands are an established treatment technology for a diverse range of polluted effluents. There is a long history of using wetlands as a unit process in treating acid mine drainage, while recent research has highlighted the potential for wetlands to buffer highly alkaline (pH>12) drainage. This paper reviews recent evidence on this topic, looking at wetlands treating acidic mine drainage, and highly alkaline leachates associated with drainage from lime-rich industrial by-products or where such residues are used as filter media in constructed wetlands for wastewater treatment. The limiting factors to the success of wetlands treating highly acidic waters are discussed with regard to design practice for the emerging application of wetlands to treat highly alkaline industrial discharges. While empirically derived guidelines (with area-adjusted contaminant removal rates typically quoted at 10 g Fe m(2)/day for influent waters pH>5.5; and 3.5-7 g acidity/m(2)/day for pH>4 to <5.5) for informing sizing of mine drainage treatment wetlands have generally been proved robust (probably due to conservatism), such data exhibit large variability within and between sites. Key areas highlighted for future research efforts include: (1) wider collation of mine drainage wetland performance data in regionalised datasets to improve empirically-derived design guidelines and (2) obtaining an improved understanding of nature of the extremophile microbial communities, microbially-mediated pollutant attenuation and rhizospheral processes in wetlands at extremes of pH. An enhanced knowledge of these (through multi-scale laboratory and field studies), will inform engineering design of treatment wetlands and assist in the move from the empirically-derived conservative sizing estimates that currently prevail to process-based optimal design guidance that could reduce costs and enhance the performance and longevity of wetlands for treating acidic and highly alkaline drainage waters.
人工湿地是一种成熟的处理技术，可用于处理各种污染废水。将湿地用作处理酸性矿山排水的单元工艺已有很长的历史，而最近的研究突出了湿地缓冲高碱性（pH>12）排水的潜力。本文综述了关于这一主题的最新证据，探讨了处理酸性矿山排水以及与富含石灰的工业副产品排水或在人工湿地中用作废水处理过滤介质的此类残渣相关的高碱性渗滤液的湿地。针对人工湿地处理高碱性工业排放这一新兴应用的设计实践，讨论了湿地处理高酸性水体成功的限制因素。虽然用于指导矿山排水处理湿地规模确定的经验性指导方针（对于进水pH>5.5，通常引用面积调整后的污染物去除率为10 g Fe m²/天；对于pH>4至<5.5，为3.5 - 7 g酸度/m²/天）总体上已被证明是可靠的（可能是由于保守性），但此类数据在不同地点之间和内部存在很大差异。未来研究工作重点突出的关键领域包括：（1）在区域化数据集中更广泛地整理矿山排水湿地性能数据，以改进基于经验的设计指导方针；（2）更好地理解极端pH值湿地中嗜极微生物群落的性质、微生物介导的污染物衰减和根际过程。对这些方面（通过多尺度实验室和现场研究）有更深入的了解，将为处理湿地的工程设计提供依据，并有助于从目前普遍采用的基于经验的保守规模估计转向基于过程的优化设计指导，从而降低成本，提高处理酸性和高碱性排水湿地的性能和使用寿命。
