Department of Community Health, Faculty of Clinical Sciences, Obafemi Awolowo University, Ile Ife, 234036, Nigeria; Department of Environmental Health Sciences, University of Ibadan, Ibadan, Nigeria
Aluko, O.O., Department of Community Health, Faculty of Clinical Sciences, Obafemi Awolowo University, Ile Ife, 234036, Nigeria; Sridhar, M.K.C., Department of Environmental Health Sciences, University of Ibadan, Ibadan, Nigeria
Strong and highly polluting leachate is continuously discharged into Omi stream and its tributaries in Ibadan, southwest Nigeria, from a municipal solid waste landfill. Previous studies have targeted physical and chemical treatment methods, which could not be implemented on site as stand-alone treatment systems. This study explored the bench-scale, trickling filter (TF) and sequencing batch reactor (SBR) treatment processes and assessed the quality of effluents produced. Leachate treatment using TF produced effluents with significant reductions (%) in suspended solids (SS) (73.17%), turbidity (71.96%), biochemical oxygen demand (BOD5) (76.69%) and ammonia (NH3) (59.50%), while SBR produced effluents with reductions in SS (62.28%), BOD5 (84.06%) and NH3 (64.83%). The dissolved oxygen of the reactors was 4.7 and 6.1mg/l, respectively, in TF and SBR. Also, NH3 values reduced marginally; however, nitrification took place significantly, but within permissible limits. The effluents produced by biological treatment processes were better in quality though the mean residual concentrations for colour, SS and dissolved solids; BOD5 and iron were above the national regulatory standards for discharge into surface water bodies. SBR gave a better effluent quality and should be combined with other treatment methods in sequence to produce quality effluents. © The Author(s) 2013.
Aerobic treatment; Environmental pollutions; Landfill leachates; Nigeria; Sequencing batch reactors; Trickling filter; Biochemical oxygen demand; Filters (for fluids); Surface waters; Turbidity; Water quality; Leachate treatment; dissolved oxygen; surface water; bioreactor; effluent; filter; landfill; leachate; municipal solid waste; oxic conditions; physicochemical property; standard (regulation); activated sludge; article; biochemical oxygen demand; chemical composition; effluent; evaluation; landfill; leaching; municipal solid waste; Nigeria; pollution; priority journal; sampling; sequencing batch reactor; suspended particulate matter; trickling filter; aerobic treatment; environmental pollution; Landfill leachates; Nigeria; sequencing batch reactor; trickling filter; Hydrogen-Ion Concentration; Nigeria; Temperature; Water Pollutants, Chemical; Ibadan; Nigeria; Oyo