title: Coupling digestion in a pilot-scale UASB reactor and electrochemical oxidation over BDD anode to treat diluted cheese whey.
abstract: The efficiency of the anaerobic treatment of cheese whey (CW) at mesophilic conditions was investigated. In addition, the applicability of electrochemical oxidation as an advanced post-treatment for the complete removal of chemical oxygen demand (COD) from the anaerobically treated cheese whey was evaluated. The diluted cheese whey, having a pH of 6.5 and a total COD of 6 g/L, was first treated in a 600-L, pilot-scale up-flow anaerobic sludge blanket (UASB) reactor. The UASB process, which was operated for 87 days at mesophilic conditions (32 ± 2 °C) at a hydraulic retention time (HRT) of 3 days, led to a COD removal efficiency between 66 and 97 %, while the particulate matter of the wastewater was effectively removed by entrapment in the sludge blanket of the reactor. When the anaerobic reactor effluent was post-treated over a boron-doped diamond (BDD) anode at 9 and 18 A and in the presence of NaCl as the supporting electrolyte, complete removal of COD was attained after 3-4 h of reaction. During electrochemical experiments, three groups of organochlorinated compounds, namely trihalomethanes (THMs), haloacetonitriles (HANs), and haloketons (HKs), as well as 1,2-dichloroethane (DCA) and chloropicrin were identified as by-products of the process; these, alongside free chlorine, are thought to increase the matrix ecotoxicity to Artemia salina.
authors.affiliation: Department of Environmental Engineering, Technical University of Crete, Polytechneioupolis, 73100, Chania, Greece.
authors.forename: Alphathanasia
authors.initials: A
authors.lastname: Katsoni
authors.forename: Dionissios
authors.initials: D
authors.lastname: Mantzavinos
authors.forename: Evan
authors.initials: E
authors.lastname: Diamadopoulos
mesh_terms: D000693:Anaerobiosis; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D055664:Electrochemical Techniques; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste / Q000032:analysis; D008894:Milk Proteins / Q000737:chemistry* / Q000378:metabolism; D010084:Oxidation-Reduction; D012722:Sewage / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods*; D000067816:Whey Proteins
chemical_list: D007220:Industrial Waste; D008894:Milk Proteins; D012722:Sewage; D000067816:Whey Proteins