Anaerobic co-digestion of the process water from waste activated sludge hydrothermally treated with primary sewage sludge. A new approach for sewage sludge management

Hydrothermal carbonization (HTC) is a suitable technology for managing wastes with a high moisture content, providing a carbon-rich and high energy density material called hydrochar and a process water (PW) with significant organic matter content. The aim of this work was to develop a new approach t...

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Detalles Bibliográficos
Autores: Villamil, J. A., Fernández Mohedano, Ángel, San Martín, J., Rodríguez Jiménez, Juan José, Rubia Romero, María de los Ángeles de la
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/696919
Acceso en línea:http://hdl.handle.net/10486/696919
https://dx.doi.org/10.1016/j.renene.2019.06.138
Access Level:acceso abierto
Palabra clave:Anaerobic digestion
HTC process water
Hydrothermal carbonization
Mesophilic and thermophilic operation
Semi-continuous operation
Sewage sludge valorization
Química
Descripción
Sumario:Hydrothermal carbonization (HTC) is a suitable technology for managing wastes with a high moisture content, providing a carbon-rich and high energy density material called hydrochar and a process water (PW) with significant organic matter content. The aim of this work was to develop a new approach to sewage sludge management involving anaerobic digestion (AD) of the PW of dewatered waste activated sludge (DWAS) with primary sewage sludge (PSS). The process was optimized by performing semi-continuous experiments with different feed mixture compositions (10% PW/90% PSS and 5% PW/95% PSS, on a COD basis), organic loading rates (OLR; 1.5 and 2.5 g COD L−1 d−1), and temperature regimes (mesophilic and thermophilic). The combination of mesophilic conditions, a 10% PW/90% PSS feed mixture and OLR of 1.5 g COD L−1 d−1 provided concentrations of volatile fatty acids <400 mg COD L−1 in addition to a methane yield (172 ± 11 mL CH4 g−1 CODadded), 1.15 times the value for the control test (100% PSS). Therefore, the energy content of hydrochar from HTC of DWAS followed by AD of the process water with primary sewage sludge enhances the valorization of this renewable residue