Co-digestion of microalgae and primary sludge: effect on biogas production and microcontaminants removal

Microalgal-based wastewater treatment plants are conceived as low cost and low energy consuming systems. The operation of these plants involves the management of primary sludge and microalgal biomass. The aim of this study is to analyse the anaerobic co-digestion of both by-products in terms of biog...

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Detalles Bibliográficos
Autores: Solé Bundó, Maria, Garfi, Marianna|||0000-0001-9234-5580, Matamoros Mercadal, Víctor, Ferrer Martí, Ivet|||0000-0002-4568-4843
Tipo de recurso: artículo
Fecha de publicación:2019
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:2117/130070
Acceso en línea:https://hdl.handle.net/2117/130070
https://dx.doi.org/10.1016/j.scitotenv.2019.01.011
Access Level:acceso abierto
Palabra clave:Biogas
Microalgae--Biotechnology
Microalgae -- Biotechnology
Algae Anaerobic digestion Bioenergy Contaminants of emerging concern Sewage sludge
Biogàs
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:Microalgal-based wastewater treatment plants are conceived as low cost and low energy consuming systems. The operation of these plants involves the management of primary sludge and microalgal biomass. The aim of this study is to analyse the anaerobic co-digestion of both by-products in terms of biogas production and contaminants of emerging concern removal. The co-digestion of microalgae and primary sludge (25/75% on a volatile solids basis) was investigated in continuous reactors and compared to microalgae mono-digestion at a hydraulic retention time of 20 days. Results showed how the co-digestion enhanced the anaerobic digestion of microalgal biomass, since primary sludge is a more readily biodegradable substrate, which increased the methane production by 65% and reduced the risk of ammonia toxicity. Regarding the contaminants, musk fragrances (galaxolide and tonalide) and triclosan showed the highest abundance on primary sludge (0.5–25 µg/g TS), whereas caffeine, methyl dihydrojasmonate and triphenyl phosphate were barely detected in both substrates (<0.1 µg/g TS). The removal of these contaminants was compound-depending and ranged from no removal to up to 90%. On the whole, microalgae mono-digestion resulted in a higher removal of selected contaminants than the co-digestion with primary sludge.