RT info:eu-repo/semantics/article T1 Simultaneous biogas upgrading and centrate treatment in an outdoors pilot scale high rate algal pond A1 Posadas Olmos, Esther A1 Marín, David A1 Blanco, Saúl A1 Lebrero Fernández, Raquel A1 Muñoz Torre, Raúl K1 Aguas residuales K1 Microalgas AB The bioconversion of biogas to biomethane coupled to centrate treatment was evaluated in an outdoors pilot scale high rate algal pond interconnected to an external CO2-H2S absorption column (AC) via settled broth recirculation. CO2-removal efficiencies ranged from 50 to 95% depending on the alkalinity of the cultivation broth and environmental conditions, while a complete H2S removal was achieved regardless of the operational conditions. A maximum CH4 concentration of 94% with a limited O2 and N2 stripping was recorded in the upgraded biogas at recycling liquid/biogas ratios in the AC of 1 and 2. Process operation at a constant biomass productivity of 15 g m−2 d−1 and the minimization of effluent generation supported high carbon and nutrient recoveries in the harvested biomass (C = 66 ± 8%, N = 54 ± 18%, P ≈ 100% and S = 16 ± 3%). Finally, a low diversity in the structure of the microalgae population was promoted by the environmental and operational conditions imposed. PB Elsevier YR 2017 FD 2017 LK http://uvadoc.uva.es/handle/10324/23531 UL http://uvadoc.uva.es/handle/10324/23531 LA eng NO Bioresource Technology , 2017, Volume 232, Pages 133–141 NO Producción Científica DS UVaDOC RD 25-abr-2024