title: Scaling-up of membraneless microbial electrolysis cells (MECs) for domestic wastewater treatment: Bottlenecks and limitations.
abstract: Microbial electrolysis cells (MECs) have the potential to become a sustainable domestic wastewater (dWW) treatment system. However, new scale-up experiences are required to gain knowledge of critical issues in MEC designs. In this study we assess the ability of two twin membraneless MEC units (that are part of a modular pilot-scale MEC) to treat dWW. Batch tests yielded COD removal efficiencies as high as 92%, with most of the hydrogen (>80% of the total production) being produced during the first 48h. During the continuous tests, MECs performance deteriorated significantly (energy consumption was relatively high and COD removal efficiencies fell below 10% in many cases), which was attributed to an inadequate configuration of the anodic chamber, insufficient mixing inside this chamber, inefficient hydrogen management on the cathode side and finally to dWW in itself. Some alternatives to the current design are suggested.
authors.affiliation: Chemical and Environmental Bioprocess Engineering Department, Natural Resources Institute (IRENA), Universidad de León, Av. de Portugal 41, 24071 León, Spain. Electronic address: adrian.escapa@unileon.es.
authors.forename: A
authors.initials: A
authors.lastname: Escapa
authors.affiliation: Chemical and Environmental Bioprocess Engineering Department, Natural Resources Institute (IRENA), Universidad de León, Av. de Portugal 41, 24071 León, Spain.
authors.forename: M I
authors.initials: MI
authors.lastname: San-Martín
authors.affiliation: Chemical and Environmental Bioprocess Engineering Department, Natural Resources Institute (IRENA), Universidad de León, Av. de Portugal 41, 24071 León, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Mateos
authors.affiliation: Chemical and Environmental Bioprocess Engineering Department, Natural Resources Institute (IRENA), Universidad de León, Av. de Portugal 41, 24071 León, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Morán
mesh_terms: D001674:Bioelectric Energy Sources; D057919:Biological Oxygen Demand Analysis; D004572:Electrolysis; D004867:Equipment Design; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater; D018508:Water Purification / Q000379:methods
chemical_list: D062065:Wastewater
keywords: Domestic wastewater; Hydrogen; Microbial electrochemical technologies; Microbial electrolysis cell; Scale up