TY - JOUR
T1 - Resilience towards organic load and activated sludge variations in co-fermentation for carboxylic acid production
AU - Perez-Esteban, N.
AU - Vives-Egea, J.
AU - Dosta, J.
AU - Astals, S.
AU - Peces, M.
N1 - Publisher Copyright:
© 2024 The Authors
PY - 2024/8
Y1 - 2024/8
N2 - Two perturbations were investigated in acidogenic co-fermentation of waste activated sludge (WAS) and food waste in continuous mesophilic fermenters: increasing the organic loading rate (OLR) and changing the WAS. A control reactor maintained an OLR of 11 gVS/(L·d), while a test reactor had a prolonged OLR change to 18 gVS/(L·d). For each OLR, two WAS were studied. The change in OLR led to differentiated fermentation product profile without compromising the fermentation yields (∼300 mgCOD/gVS). At 11 gVS/(L·d), the product profile was dominated by acetic, butyric, and propionic acids while at 18 gVS/(L·d) it shifted to acetic acid, ethanol, and caproic acid. Reverting the OLR also reverted the fermentation profile. The biomass immigration with the WAS changed the fermentation microbial structure and introduced acetic acid-consuming methanogens, which growth was only delayed by the OLR increase. Microbial monitoring and post-fermentation tests can be used for early detection of acetic acid-consuming events.
AB - Two perturbations were investigated in acidogenic co-fermentation of waste activated sludge (WAS) and food waste in continuous mesophilic fermenters: increasing the organic loading rate (OLR) and changing the WAS. A control reactor maintained an OLR of 11 gVS/(L·d), while a test reactor had a prolonged OLR change to 18 gVS/(L·d). For each OLR, two WAS were studied. The change in OLR led to differentiated fermentation product profile without compromising the fermentation yields (∼300 mgCOD/gVS). At 11 gVS/(L·d), the product profile was dominated by acetic, butyric, and propionic acids while at 18 gVS/(L·d) it shifted to acetic acid, ethanol, and caproic acid. Reverting the OLR also reverted the fermentation profile. The biomass immigration with the WAS changed the fermentation microbial structure and introduced acetic acid-consuming methanogens, which growth was only delayed by the OLR increase. Microbial monitoring and post-fermentation tests can be used for early detection of acetic acid-consuming events.
KW - Excess sludge
KW - Microbial community
KW - Mixed-culture fermentation
KW - Organic fraction of municipal solid waste
KW - Volatile fatty acids
UR - http://www.scopus.com/inward/record.url?scp=85197054281&partnerID=8YFLogxK
U2 - 10.1016/j.biortech.2024.131034
DO - 10.1016/j.biortech.2024.131034
M3 - Journal article
C2 - 38925408
AN - SCOPUS:85197054281
SN - 0960-8524
VL - 406
JO - Bioresource Technology
JF - Bioresource Technology
M1 - 131034
ER -