Limited artificial aireation as a strategy for improving the removal of contaminants in constructed wetland treating domestic wastewater

Autor: Diego Paredes, Carlos-Andrés Ramírez-Vargas, Cristhian Galeano León
Přispěvatelé: Arias, Carlos, Ramirez-Vargas, Carlos A., Peñacoba-Antona, Lorena, Brix, Hans
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Paredes, D, Ramirez-Vargas, C A & Galeano León, C 2019, Limited artificial aireation as a strategy for improving the removal of contaminants in constructed wetland treating domestic wastewater . in C Arias, C A Ramirez-Vargas, L Peñacoba-Antona & H Brix (eds), Book of Abstracts 8th International Symposium on Wetland Pollutant Dynamics and Control : 17 – 21 June, 2019, Aarhus University, Denmark . Aarhus University, Aarhus, pp. 417, WETPOL2019: 8th International Symposium on Wetland Pollutants Dynamics and Control, Aarhus, Denmark, 17/06/2019 . < http://wetpol.com/wp-content/uploads/2019/06/Book_of_Abstracts_WETPOL2019.pdf >
Aarhus University
Popis: Due to its simple operation and maintenance, constructed wetlands are considered a low cost wastewater treatment alternative, being especially suitable for developing countries. Constructed wetlands have been successfully implemented for the control and removal of pollutants in various types of wastewater worldwide, however, their capacity and efficiency for the removal of nutrients continues to be low. In typical wetland configurations, for example, subsurface horizontal flow constructed wetlands (SSHFCW), the removal of total nitrogen is quite variable reaching values around 50% in most cases. Nitrification- denitrification pathway has been identified as the main mechanism for Nitrogen removal, however, limited natural oxygen transfer in affects the process. This is why the purpose of this research is to evaluate the effect of limited artificial aeration as a strategy to improve the nitrogen and organic matter removal SSHFCW.For the research six (6) laboratory scale experimental units (0.8 m * 0.30m * 0.50m) with gravel as support medium and planted with Phragmites australis has been used. The air supply is made through diffuser stones distributed longitudinally in the bottom of the units and 8 pulses of 30 minutes are applied along the day. The effect of limited aeration applied in different lengths has been compared with units without aeration with a hydraulic retention time of two (2) days during three (3) months of monitoring.According to the obtained results (Table 1), the units with aeration have achieved higher BOD5 removal efficiencies in comparison with the obtained values in the control units (without additional aeration). For total nitrogen, the units with aeration have achieved removal efficiencies of 73%, while the control units reached 58%. On the other hand, the removal efficiency of NH3-N in the units with controlled aeration was around 75%, while the units without aeration 50% removal was obtained. The removal of TSS reached in the units with aeration was 78%, while in the control units were found 54% values. It is evident that the application of limited artificial aeration constitutes a valuable tool for improving total nitrogen removal in subsurface horizontal flow constructed wetlands.
Databáze: OpenAIRE