title: Effects of pre-fermentation and pulsed-electric-field treatment of primary sludge in microbial electrochemical cells.
abstract: The aim of this study was to investigate the combination of two technologies - pulsed electric field (PEF) pre-treatment and semi-continuous pre-fermentation of primary sludge (PS) - to produce volatile fatty acids (VFAs) as the electron donor for microbial electrolysis cells (MECs). Pre-fermentation with a 3-day solids retention time (SRT) led to the maximum generation of VFAs, with or without pretreatment of the PS through pulsed-electric-fields (PEF). PEF treatment before fermentation enhanced the accumulation of the preferred VFA, acetate, by 2.6-fold. Correspondingly, MEC anodes fed with centrate from 3-day pre-fermentation of PEF-treated PS had a maximum current density ∼3.1 A/m(2), which was 2.4-fold greater than the control pre-fermented centrate. Over the full duration of batch MEC experiments, using pre-fermented centrate led to successful performance in terms of Coulombic efficiency (95%), Coulombic recovery (80%), and COD-removal efficiency (85%).
authors.affiliation: Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA; School of Sustainable Engineering and the Built Environment, Arizona State University, P.O. Box 875306, Tempe, AZ 85287-5306, USA.
authors.forename: Dongwon
authors.initials: D
authors.lastname: Ki
authors.affiliation: Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA.
authors.forename: Prathap
authors.initials: P
authors.lastname: Parameswaran
authors.affiliation: Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA.
authors.forename: Sudeep C
authors.initials: SC
authors.lastname: Popat
authors.affiliation: Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA; School of Sustainable Engineering and the Built Environment, Arizona State University, P.O. Box 875306, Tempe, AZ 85287-5306, USA.
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Rittmann
authors.affiliation: Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA; School for Engineering of Matter Transport and Energy, Arizona State University, 501 E. Tyler Mall ECG 301, Tempe, AZ 85287, USA. Electronic address: cit@asu.edu.
authors.forename: César I
authors.initials: CI
authors.lastname: Torres
mesh_terms: D001674:Bioelectric Energy Sources / Q000382:microbiology*; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D004560:Electricity; D055664:Electrochemical Techniques; D005232:Fatty Acids, Volatile / Q000032:analysis; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D008697:Methane / Q000032:analysis; D012722:Sewage / Q000382:microbiology*
chemical_list: D005232:Fatty Acids, Volatile; D012722:Sewage; D008697:Methane
keywords: Microbial electrolysis cell; Pre-fermentation; Pre-treatment; Two-stage anaerobic treatment