Ingeniería y Universidad
Print version ISSN 0123-2126
SILVA-VINASCO, Juan Pablo and VALVERDE-SOLIS, Arlyn. Assessment of Greenhouse Effect Gases in Sub-Superficial Flow Constructed Wetlands. Ing. Univ. [online]. 2011, vol.15, n.2, pp. 519-533. ISSN 0123-2126.
In developing countries, constructed wetlands are attractive systems with low operational and maintenance costs in terms of wastewater treatment. However, by reducing the pollution load of wastewater they might contribute to produce some greenhouse gases such as methane, carbon dioxide and nitrous oxide. This research compared two ornamental species and assessed the emissions of these gases through the use of static cameras in three full-scale constructed wetlands of which two were planted: one with Heliconia psittacorum, one with Phragmites australis, and the third one, which was not planted, was the control wetland. Each one of them received a hydraulic load of 3.5 m3d-1, which is equivalent to a nominal hydraulic retention time of 1.8 days. In addition, physicochemical characterizations were performed. Efficiency was between 66.2% and 87.8% for COD; on average, the temperature was between 29 and 31 °C, and the pH was between 6.3 and 7, in both planted and unplanted systems. Additionally, no significant differences in the vegetation studied were found. We conclude that the ornamental species used do not affect the emission of greenhouse gases in the systems analyzed.
Keywords : Constructed wetlands; wastewater; Greenhouse gases; methane.