title: Submersible microbial desalination cell for simultaneous ammonia recovery and electricity production from anaerobic reactors containing high levels of ammonia.
abstract: High ammonia concentration in anaerobic reactors can seriously inhibit the anaerobic digestion process. In this study, a submersible microbial desalination cell (SMDC) was developed as an innovative method to lower the ammonia level in a continuous stirred tank reactor (CSTR) by in situ ammonia recovery and electricity production. In batch experiment, the ammonia concentration in the CSTR decreased from 6 to 0.7 g-N/L during 30 days, resulting in an average recovery rate of 80 g-N/m(2)/d. Meanwhile, a maximum power density of 0.71±0.5 W/m(2) was generated at 2.85 A/m(2). Both current driven NH4(+) migration and free NH3 diffusion were identified as the mechanisms responsible for the ammonia transportation. With an increase in initial ammonia concentration and a decrease in external resistance, the SMDC performance was enhanced. In addition, the coexistence of other cations in CSTR or cathode had no negative effect on the ammonia transportation.
authors.affiliation: Department of Environmental Engineering, Building 113, Technical University of Denmark, DK-2800 Lyngby, Denmark. Electronic address: yifz@env.dtu.dk.
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Environmental Engineering, Building 113, Technical University of Denmark, DK-2800 Lyngby, Denmark.
authors.forename: Irini
authors.initials: I
authors.lastname: Angelidaki
mesh_terms: D000641:Ammonia / Q000302:isolation & purification* / Q000494:pharmacology; D000693:Anaerobiosis / Q000187:drug effects; D001673:Biodegradation, Environmental / Q000187:drug effects; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D019149:Bioreactors / Q000382:microbiology*; D002412:Cations / Q000494:pharmacology; D004560:Electricity; D012965:Sodium Chloride / Q000302:isolation & purification*; D013816:Thermodynamics; D013997:Time Factors; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
chemical_list: D002412:Cations; D012965:Sodium Chloride; D000641:Ammonia
keywords: Ammonia recovery; Anaerobic digestion; CSTR reactor; Power generation; Submersible microbial desalination cell