title: Electrocoagulation treatment of peat bog drainage water containing humic substances.
abstract: Electrocoagulation (EC) treatment of 100 mg/L synthetic wastewater (SWW) containing humic acids was optimized (achieving 90% CODMn and 80% DOC removal efficiencies), after which real peat bog drainage waters (PBDWs) from three northern Finnish peat bogs were also treated. High pollutant removal efficiencies were achieved: Ptot, TS, and color could be removed completely, while Ntot, CODMn, and DOC/TOC removal efficiencies were in the range of 33-41%, 75-90%, and 62-75%, respectively. Al and Fe performed similarly as the anode material. Large scale experiments (1 m(3)) using cold (T = 10-11 °C) PBDWs were also conducted successfully, with optimal treatment times of 60-120 min (applying current densities of 60-75 A/m(2)). Residual values of Al and Fe (complete removal) were lower than their initial values in the EC-treated PBDWs. Electricity consumption and operational costs in optimum conditions were found to be low and similar for all the waters studied: 0.94 kWh/m(3) and 0.15 €/m(3) for SWW and 0.35-0.70 kWh/m(3) and 0.06-0.12 €/m(3) for the PBDWs (large-scale). Thus, e.g. solar cells could be considered as a power source for this EC application. In conclusion, EC treatment of PBDW containing humic substances was shown to be feasible.
authors.affiliation: University of Oulu, Research Unit of Sustainable Chemistry, P.O. Box 3000, 90014 Oulu, Finland.
authors.forename: V
authors.initials: V
authors.lastname: Kuokkanen
authors.affiliation: University of Oulu, Research Unit of Sustainable Chemistry, P.O. Box 3000, 90014 Oulu, Finland. Electronic address: ville.kuokkanen@oulu.fi.
authors.forename: T
authors.initials: T
authors.lastname: Kuokkanen
authors.affiliation: University of Oulu, Thule Institute, Cewic, P.O. Box 4300, 90014 Oulu, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Rämö
authors.affiliation: University of Oulu, Research Unit of Sustainable Chemistry, P.O. Box 3000, 90014 Oulu, Finland; University of Jyvaskyla, Kokkola University Consortium Chydenius, P. O. Box 567, FI-67701 Kokkola, Finland.
authors.forename: U
authors.initials: U
authors.lastname: Lassi
mesh_terms: D057919:Biological Oxygen Demand Analysis; D003116:Color; D004572:Electrolysis; D005387:Finland; D006812:Humic Substances; D007220:Industrial Waste; D012987:Soil; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D006812:Humic Substances; D007220:Industrial Waste; D012987:Soil; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Electrocoagulation (EC); Humic substances; Large-scale experiments; Peat bog drainage water; Techno-economic analysis