Evaluation of leachate treatment by trickling filter and sequencing batch reactor processes in Ibadan, Nigeria
Waste Management and Research
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
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