Optimization of the anaerobic co-digestion of pasteurized slaughterhouse waste, pig slurry and glycerine

The feasibility of co-digestion of blends of two different animal by-products (pig manure and pasteurized slaughterhouse waste) and recovered glycerine was studied in mesophilic conditions. Experiments were performed in a lab-scale CSTR along 490 days, with a hydraulic retention time of 21–33 days a...

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Detalles Bibliográficos
Autores: Rodríguez-Abalde, Ángela, Flotats Ripoll, Xavier|||0000-0002-8721-0996, Fernández García, Belén
Tipo de recurso: artículo
Fecha de publicación:2016
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:2117/102611
Acceso en línea:https://hdl.handle.net/2117/102611
https://dx.doi.org/10.1016/j.wasman.2016.12.022
Access Level:acceso abierto
Palabra clave:Waste management
Co-digestion
Slaughterhouse waste
Pig slurry
Glycerin
C/N ratio
Residus -- Planificació
Àrees temàtiques de la UPC::Desenvolupament humà i sostenible::Enginyeria ambiental::Tractament dels residus
Descripción
Sumario:The feasibility of co-digestion of blends of two different animal by-products (pig manure and pasteurized slaughterhouse waste) and recovered glycerine was studied in mesophilic conditions. Experiments were performed in a lab-scale CSTR along 490 days, with a hydraulic retention time of 21–33 days and with a step-wise increased organic loading rate, by adding and/or changing the wastes ratio, from 0.8 to 3.2 kgCOD m-3 d-1. The best methane production rate (0.64 Nm3CH4 m-3 d-1) represented an increment of 2.9-fold the initial one (0.22 Nm3CH4 m-3 d-1 with pig manure solely). It was attained with a ternary mixture composed, in terms of inlet volatile solids, by 35% pig slurry, 47% pasteurized slaughterhouse waste and 18% glycerine. This blend was obtained through a stepwise C/N adjustment: this strategy led to a more balanced biodegradation due to unstressed bacterial populations through the performance, showed by the VFA-related indicators. Besides this, an improved methane yield (+153%) and an organic matter removal efficiency (+83%), regarding the digestion of solely pig slurry, were attained when the C/N ratio was adjusted to 10.3.