RT info:eu-repo/semantics/article
T1 Development of a control strategy to cope with biogas flowrate variations during photosynthetic biogas upgrading
A1 Rodero Raya, María del Rosario
A1 Carvajal, Andrea
A1 Castro, Víctor
A1 Navia, Daniel
A1 Prada Moraga, César de
A1 Lebrero Fernández, Raquel
A1 Muñoz Torre, Raúl
AB The design and evaluation of a control system for a photosynthetic biogas upgrading unit was successfully carried out in this study. This control system ensured a specific biomethane quality under any disturbance in the biogas flowrate. The recycling liquid flowrate, and indirectly the liquid to biogas (L/G) ratio, was selected as the manipulated variable in order to maintain the CO2 and O2 content of biomethane, and therefore comply with the requirements for its use as natural gas substitute (<2.5% and <1.0%, respectively). The control system was able to maintain the biomethane CO2 content below the set point value under a stepwise increase in the biogas flowrate from 60 to 150 ml/min, together with negligible H2S concentrations and an O2 stripping from the recycling liquid to the biomethane lower than 1%, thus obtaining a consistent biomethane quality over time. On the contrary, the biomethane CO2 content increased up to 13.2% under this stepwise increase in the biogas flowrate without control system. Successful results were also obtained when the control system was challenged with stepwise surges in the biogas flowrate between 60 and 120 ml/min under different temperatures (15 and 35 ºC) and inorganic carbon concentrations (1500, 500 and 100 mg/L) when the recycling liquid entering the absorption column presented a pH 10. However, the high liquid flowrates required at a cultivation broth pH of 8.5 as a result of the low CO2 mass transfer led to an excessive O2 desorption to the biomethane, resulting in biomethane O2 contents >1%.
PB Elsevier
SN 0961-9534
YR 2019
FD 2019
LK https://uvadoc.uva.es/handle/10324/83068
UL https://uvadoc.uva.es/handle/10324/83068
LA spa
NO Biomass and Bioenergy,  December 2019, Volume 131,105414
NO Producción Científica
DS UVaDOC
RD 23-mar-2026