title: Vertical-flow constructed wetlands treating domestic wastewater contaminated by hydrocarbons.
abstract: The aim was to compare the impact of different design (aggregate size) and operational (contact time, empty time and chemical oxygen demand (COD) loading) variables on the long-term and seasonal performance of vertical-flow constructed wetland filters operated in tidal flow mode before and after a one-off spill of diesel. Ten different vertical-flow wetland systems were planted with Phragmites australis (Cav.) Trin. ex Steud. (common reed). Approximately 130 g of diesel fuel was poured into four wetland filters. Before the spill, compliance with secondary wastewater treatment standards was achieved by all wetlands regarding ammonia-nitrogen (NH4-N), nitrate-nitrogen (NO₃-N) and suspended solids (SS), and non-compliance was recorded for biochemical oxygen demand and ortho-phosphate-phosphorus (PO₄-P). Higher COD inflow concentrations had a significantly positive impact on the treatment performance for COD, PO₄-P and SS. The wetland with the largest aggregate size had the lowest mean NO₃-N outflow concentration. However, the results were similar regardless of aggregate size and resting time for most variables. Clear seasonal outflow concentration trends were recorded for COD, NH4-N and NO₃-N. No filter clogging was observed. The removal efficiencies dropped for those filters impacted by the diesel spill. The wetlands system shows a good performance regarding total petroleum hydrocarbon (TPH) removal.
authors: Civil Engineering Research Group, The University of Salford, School of Computing, Science and Engineering, Newton Building, Salford, Greater Manchester M5 4WT, UK E-mail: r.h.al-isawi@edu.salford.ac.uk.
authors: R H K
authors: RH
authors: Al-Isawi
authors: Civil Engineering Research Group, The University of Salford, School of Computing, Science and Engineering, Newton Building, Salford, Greater Manchester M5 4WT, UK E-mail: r.h.al-isawi@edu.salford.ac.uk.
authors: A
authors: A
authors: Sani
authors: Civil Engineering Research Group, The University of Salford, School of Computing, Science and Engineering, Newton Building, Salford, Greater Manchester M5 4WT, UK E-mail: r.h.al-isawi@edu.salford.ac.uk.
authors: S A A A N
authors: SA
authors: Almuktar
authors: Civil Engineering Research Group, The University of Salford, School of Computing, Science and Engineering, Newton Building, Salford, Greater Manchester M5 4WT, UK E-mail: r.h.al-isawi@edu.salford.ac.uk.
authors: M
authors: M
authors: Scholz
mesh_terms: D064751:Ammonium Compounds / Q000032:analysis; D005374:Filtration; D005742:Gasoline / Q000032:analysis; D009566:Nitrates / Q000032:analysis; D059392:Petroleum Pollution / Q000032:analysis; D010710:Phosphates / Q000032:analysis; D012621:Seasons; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*; D060753:Water Quality; D053833:Wetlands
chemical_list: D064751:Ammonium Compounds; D005742:Gasoline; D009566:Nitrates; D010710:Phosphates; D062065:Wastewater; D014874:Water Pollutants, Chemical