Upflow anaerobic sludge blanket in microalgae-based sewage treatment: co-digestion for improving biogas production

Upflow anaerobic sludge blanket (UASB) reactors are widely used to treat domestic sewage and frequently require post-treatment. Little is known about the use of high rate algal ponds (HRAP) for post-treating UASB reactors’ effluent. This study aimed to evaluate a UASB reactor followed by a HRAP in t...

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Detalles Bibliográficos
Autores: Castro, Lucas Vassalle de, Díez Montero, Rubén|||0000-0001-8435-0195, Machado, Alcino Trindade Rosa, Moreira, Camila, Ferrer Martí, Ivet|||0000-0002-4568-4843, Mota, Cesar R., Passos, Fabiana Lopes del Rei|||0000-0001-7501-988X
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/177990
Acceso en línea:https://hdl.handle.net/2117/177990
https://dx.doi.org/10.1016/j.biortech.2019.122677
Access Level:acceso abierto
Palabra clave:Biogas
Sewage -- Purification
Microalgae -- Biotechnology
Bioenergy recovery
High rate algal pond
UASB reactor
Sewage
Biogàs
Aigües residuals -- Depuració
Microalgues -- Biotecnologia
Àrees temàtiques de la UPC::Energies::Recursos energètics renovables::Biogàs
Àrees temàtiques de la UPC::Desenvolupament humà i sostenible::Enginyeria ambiental::Tractament de l'aigua
Descripción
Sumario:Upflow anaerobic sludge blanket (UASB) reactors are widely used to treat domestic sewage and frequently require post-treatment. Little is known about the use of high rate algal ponds (HRAP) for post-treating UASB reactors’ effluent. This study aimed to evaluate a UASB reactor followed by a HRAP in terms of sewage treatment efficiency and biogas production, during one year at demonstration–scale. The UASB reactor co-treated raw sewage and the harvested microalgal biomass from the HRAP, which was recirculated to the reactor. An identical UASB reactor, treating only raw sewage, was used as control. The results showed an overall removal of 65% COD and 61% N-NH4 in the system. Furthermore, methane yield was increased by 25% after anaerobic co-digestion with microalgae, from 156 to 211 NL CH4 kg-1 VS. An energy assessment was performed and showed a positive energy balance, with a net ratio of 2.11 to the annual average.