title: A novel anaerobic electrochemical membrane bioreactor (AnEMBR) with conductive hollow-fiber membrane for treatment of low-organic strength solutions.
abstract: A new anaerobic treatment system that combined a microbial electrolysis cell (MEC) with membrane filtration using electrically conductive, porous, nickel-based hollow-fiber membranes (Ni-HFMs) was developed to treat low organic strength solution and recover energy in the form of biogas. This new system is called an anaerobic electrochemical membrane bioreactor (AnEMBR). The Ni-HFM served the dual function as the cathode for hydrogen evolution reaction (HER) and the membrane for filtration of the effluent. The AnEMBR system was operated for 70 days with synthetic acetate solution having a chemical oxygen demand (COD) of 320 mg/L. Removal of COD was >95% at all applied voltages tested. Up to 71% of the substrate energy was recovered at an applied voltage of 0.7 V as methane rich biogas (83% CH4; <1% H2) due to biological conversion of the hydrogen evolved at the cathode to methane. A combination of factors (hydrogen bubble formation, low cathode potential and localized high pH at the cathode surface) contributed to reduced membrane fouling in the AnEMBR compared to the control reactor (open circuit voltage). The net energy required to operate the AnEMBR system at an applied voltage of 0.7 V was significantly less (0.27 kWh/m3) than that typically needed for wastewater treatment using aerobic membrane bioreactors (1-2 kWh/m3).
authors.affiliation: King Abdullah University of Science and Technology, Biological and Environmental Sciences and Engineering Division, Water Desalination and Reuse Center , Thuwal 23955-6900, Saudi Arabia.
authors.forename: Krishna P
authors.initials: KP
authors.lastname: Katuri
authors.forename: Craig M
authors.initials: CM
authors.lastname: Werner
authors.forename: Rodrigo J
authors.initials: RJ
authors.lastname: Jimenez-Sandoval
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Sungil
authors.initials: S
authors.lastname: Jeon
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Logan
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Lai
authors.forename: Gary L
authors.initials: GL
authors.lastname: Amy
authors.forename: Pascal E
authors.initials: PE
authors.lastname: Saikaly
mesh_terms: D000693:Anaerobiosis; D057219:Biofouling; D019149:Bioreactors; D004560:Electricity; D004563:Electrochemistry / Q000295:instrumentation*; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D009930:Organic Chemicals / Q000302:isolation & purification*; D010539:Permeability; D011312:Pressure; D012996:Solutions; D018508:Water Purification / Q000295:instrumentation* / Q000379:methods*; D060753:Water Quality
chemical_list: D008567:Membranes, Artificial; D009930:Organic Chemicals; D012996:Solutions