Syntrophic interactions between H2-scavenging and anode-respiring bacteria can improve current density in microbial electrochemical cells
•High current density (14.6A/m2) can be achieved from the MEC fed with digestate.•COD removal was improved up to 96% in the MEC.•Methane production was as small as ∼3% of removed COD.•Homoacetogens outcompeted methanogens due to the syntrophy with ARB. High current density of 10.0–14.6A/m2 and COD r...
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Published in | Bioresource technology Vol. 153; pp. 245 - 253 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Kidlington
Elsevier Ltd
01.02.2014
Elsevier |
Subjects | |
Online Access | Get full text |
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Summary: | •High current density (14.6A/m2) can be achieved from the MEC fed with digestate.•COD removal was improved up to 96% in the MEC.•Methane production was as small as ∼3% of removed COD.•Homoacetogens outcompeted methanogens due to the syntrophy with ARB.
High current density of 10.0–14.6A/m2 and COD removal up to 96% were obtained in a microbial electrochemical cell (MEC) fed with digestate at hydraulic retention time (HRT) of 4d and 8d. Volatile fatty acids became undetectable in MEC effluent (HRT 8d), except for trivial acetate (4.16±1.86mgCOD/L). Accumulated methane only accounted for 3.42% of ΔCOD. Pyrosequencing analyses showed abundant fermenters (Kosmotoga spp.) and homoacetogens (Treponema spp.) in anolytes. In anode biofilm, propionate fermenters (Kosmotoga, and Syntrophobacter spp.), homoacetogens (Treponema spp.), and anode-respiring bacteria (ARB) (Geobacter spp. and Dysgonomonas spp.) were dominant. These results imply that syntrophic interactions among fermenters, homoacetogens and ARB would allow MECs to maintain high current density and coulombic efficiency. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0960-8524 1873-2976 |
DOI: | 10.1016/j.biortech.2013.11.077 |