TY - JOUR
T1 - In-situ biogas upgrading with pulse H2 additions
T2 - The relevance of methanogen adaption and inorganic carbon level
AU - Agneessens, Laura Mia
AU - Ottosen, Lars Ditlev Mørck
AU - Voigt, Niels Vinther
AU - Nielsen, Jeppe Lund
AU - de Jonge, Nadieh
AU - Fischer, Christian Holst
AU - Kofoed, Michael Vedel Wegener
N1 - Copyright © 2017 Elsevier Ltd. All rights reserved.
PY - 2017/6
Y1 - 2017/6
N2 - Surplus electricity from fluctuating renewable power sources may be converted to CH4 via biomethanisation in anaerobic digesters. The reactor performance and response of methanogen population of mixed-culture reactors was assessed during pulsed H2 injections. Initial H2 uptake rates increased immediately and linearly during consecutive pulse H2 injections for all tested injection rates (0.3 to 1.7LH2/Lsludge/d), while novel high throughput mcrA sequencing revealed an increased abundance of specific hydrogenotrophic methanogens. These findings illustrate the adaptability of the methanogen population to H2 injections and positively affects the implementation of biomethanisation. Acetate accumulated by a 10-fold following injections exceeding a 4:1 H2:CO2 ratio and may act as temporary storage prior to biomethanisation. Daily methane production decreased for headspace CO2 concentrations below 12% and may indicate a high sensitivity of hydrogenotrophic methanogens to CO2 limitation. This may ultimately decide the biogas upgrading potential which can be achieved by biomethanisation.
AB - Surplus electricity from fluctuating renewable power sources may be converted to CH4 via biomethanisation in anaerobic digesters. The reactor performance and response of methanogen population of mixed-culture reactors was assessed during pulsed H2 injections. Initial H2 uptake rates increased immediately and linearly during consecutive pulse H2 injections for all tested injection rates (0.3 to 1.7LH2/Lsludge/d), while novel high throughput mcrA sequencing revealed an increased abundance of specific hydrogenotrophic methanogens. These findings illustrate the adaptability of the methanogen population to H2 injections and positively affects the implementation of biomethanisation. Acetate accumulated by a 10-fold following injections exceeding a 4:1 H2:CO2 ratio and may act as temporary storage prior to biomethanisation. Daily methane production decreased for headspace CO2 concentrations below 12% and may indicate a high sensitivity of hydrogenotrophic methanogens to CO2 limitation. This may ultimately decide the biogas upgrading potential which can be achieved by biomethanisation.
KW - Journal Article
U2 - 10.1016/j.biortech.2017.02.016
DO - 10.1016/j.biortech.2017.02.016
M3 - Journal article
C2 - 28285216
SN - 0960-8524
VL - 233
SP - 256
EP - 263
JO - Bioresource Technology
JF - Bioresource Technology
ER -