Influence of hydrothermal pretreatment on microalgal biomass anaerobic digestion and bioenergy production

Microalgal biomass grown in wastewater treatment raceway ponds may be valorised producing bioenergy through anaerobic digestion. However, pretreatment techniques seem to be necessary for enhancing microalgae methane yield. In this study, hydrothermal pretreatment was studied prior to batch and conti...

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Detalles Bibliográficos
Autores: Passos, Fabiana Lopes del Rei|||0000-0001-7501-988X, Ferrer Martí, Ivet|||0000-0002-4568-4843
Tipo de recurso: artículo
Fecha de publicación:2015
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:2117/26439
Acceso en línea:https://hdl.handle.net/2117/26439
https://dx.doi.org/10.1016/j.watres.2014.10.015
Access Level:acceso abierto
Palabra clave:Biogas
Biomass energy
Algae
Bioenergy
Methane
Microalgae
Wastewater
SCENEDESMUS SP BIOMASS
METHANE PRODUCTION
MICROWAVE PRETREATMENT
THERMAL PRETREATMENT
BIOGAS PRODUCTION
Biogàs
Energia de la biomassa
Algues -- Biotecnologia
Àrees temàtiques de la UPC::Energies
Àrees temàtiques de la UPC::Energies::Recursos energètics renovables::Biogàs
Descripción
Sumario:Microalgal biomass grown in wastewater treatment raceway ponds may be valorised producing bioenergy through anaerobic digestion. However, pretreatment techniques seem to be necessary for enhancing microalgae methane yield. In this study, hydrothermal pretreatment was studied prior to batch and continuous reactors. The pretreatment increased organic matter solubilisation (8-13%), anaerobic digestion rate (30-90%) and final methane yield (17-39%) in batch tests. The highest increase was attained with the pretreatment at 130 degrees C for 15 min, which was attested in a laboratory-scale continuous reactor operated at a hydraulic retention time of 20 days with an average organic loading rate of 0.7 g VS/L center dot day. The methane yield increased from 0.12 to 0.17 L CH4/g VS (41%) in the pretreated digester as compared to the control. Microscopic images of microalgal biomass showed that pretreated cells had unstructured organelles and disrupted cell wall external layer, which may enhance the hydrolysis. Indeed, images of the pretreated reactor digestate showed how cells were more degraded than in the control reactor. (C) 2014 Elsevier Ltd. All rights reserved.