RT info:eu-repo/semantics/article
T1 Biogas valorization via continuous polyhydroxybutyrate production by Methylocystis hirsuta in a bubble column bioreactor
A1 Rodríguez Muñoz, Yadira
A1 Firmino, Paulo Igor Milen
A1 Pérez, Víctor
A1 Lebrero Fernández, Raquel
A1 Muñoz Torre, Raúl
K1 Bioplásticos
K1 Biorrefinería
K1 Bioplastics
K1 Biorefinery
K1 23 Química
K1 33 Ciencias Tecnológicas
AB Creating additional value out of biogas during waste treatment has become a priority in past years. Biogas bioconversion into valuable bioproducts such as biopolymers has emerged as a promising strategy. This work assessed the operational feasibility of a bubble column bioreactor (BCB) implemented with gas recirculation and inoculated with a polyhydroxybutyrate (PHB)-producing strain using biogas as substrate. The BCB was initially operated at empty bed residence times (EBRTs) ranging from 30 to 120 min and gas recirculation ratios (R) from 0 to 30 to assess the gas-to-liquid mass transfer and bioconversion of CH4. Subsequently, the BCB was continuously operated at a R of 30 and an EBRT of 60 min under excess of nitrogen and nitrogen feast-famine cycles of 24 h:24 h to trigger PHB synthesis. Gas recirculation played a major role in CH4 gas–liquid transfer, providing almost fourfold higher CH4 elimination capacities (~41 g CH4 m−3 h−1) at the highest R and EBRT of 60 min. The long-term operation under N excess conditions entailed nitrite accumulation (induced by O2 limiting conditions) and concurrent methanotrophic activity inhibition above ~60 mg N-NO2− L−1. Adjusting the N-NO3− supply to match microbial N demand successfully prevented nitrite accumulation. Finally, the N feast-famine 24 h:24 h strategy supported a stable CH4 conversion with a removal efficiency of 70% along with a continuous PHB production, which yielded PHB accumulations of 14.5 ± 2.9% (mg PHB mg−1 total suspended solids × 100). These outcomes represent the first step towards the integration of biogas biorefineries into conventional anaerobic digestion plants.
PB Elsevier
SN 0956-053X
YR 2020
FD 2020
LK https://uvadoc.uva.es/handle/10324/46752
UL https://uvadoc.uva.es/handle/10324/46752
LA eng
NO Waste Management, 2020, vol. 113, p. 395-403
NO Producción Científica
DS UVaDOC
RD 28-nov-2024