Vermifiltration as a green solution to promote digestate reuse in agriculture in small-scale farms

Digestates from low-tech digesters need to be post-treated to ensure their safe agricultural reuse. This study evaluated, for the first time, vermifiltration as a post-treatment for the digestate from a low-tech digester implemented in a small-scale farm, treating cattle manure and cheese whey under...

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Detalles Bibliográficos
Autores: Cucina, Mirko, Castro, Liliana, Font Pomarol, Jana, Escalante, Humberto, Muñoz Muñoz, Alexander, Ferrer Martí, Ivet|||0000-0002-4568-4843, Garfi, Marianna|||0000-0001-9234-5580
Tipo de recurso: artículo
Fecha de publicación:2024
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:2117/420903
Acceso en línea:https://hdl.handle.net/2117/420903
https://dx.doi.org/10.1016/j.jenvman.2024.122164
Access Level:acceso embargado
Palabra clave:Anaerobic digestion
Biofertilizer
Biogas
Digestate
Low-tech digester
Nutrients recovery
Vermifiltration
Àrees temàtiques de la UPC::Desenvolupament humà i sostenible::Enginyeria ambiental::Tractament dels residus
Descripción
Sumario:Digestates from low-tech digesters need to be post-treated to ensure their safe agricultural reuse. This study evaluated, for the first time, vermifiltration as a post-treatment for the digestate from a low-tech digester implemented in a small-scale farm, treating cattle manure and cheese whey under psychrophilic conditions. Vermifiltration performance was monitored in terms of solids, organic matter, nutrients, and pathogens removal efficiency. In addition, the growth of earthworms (Eisenia foetida) and their role in the process was evaluated. Finally, the vermicompost and the effluent of the vermifilter were characterized in order to assess their potential reuse in agriculture. Vermifilters showed high removal efficiency of chemical oxygen demand (55–90%), total solids (60–80%), ammonium nitrogen (83–97%), and phosphate-P (28–49%). Earthworms effectively grew and reproduced on digestate (i.e. earthworms number increased by 183%), enhancing the vermifiltration performance, while reducing clogging and odour-related issues. Both the vermicompost and effluent produced complied with legislation limits established for soil improvers and wastewater for fertigation, respectively. Indeed, there was an absence of pathogens and non-detectable heavy metals concentrations. Vermifiltration may be thus considered a suitable post-treatment option for the digestate from low-tech digesters, allowing for its safe agricultural reuse and boosting the circular bioeconomy in small-scale farms.