title: Co-digestion of cattle manure with food waste and sludge to increase biogas production.
abstract: Anaerobic co-digestion strategies are needed to enhance biogas production, especially when treating certain residues such as cattle/pig manure. This paper presents a study of co-digestion of cattle manure with food waste and sewage sludge. With the aim of maximising biogas yields, a series of experiments were carried out under mesophilic and thermophilic conditions using continuously stirred-tank reactors, operating at different hydraulic residence times. Pretreatment with ultrasound was also applied to compare the results with those obtained with non-pretreated waste. Specific methane production decreases when increasing the OLR and decreasing HRT. The maximum value obtained was 603 LCH(4)/kg VS(feed) for the co-digestion of a mixture of 70% manure, 20% food waste and 10% sewage sludge (total solid concentration around 4%) at 36°C, for an OLR of 1.2g VS/L day. Increasing the OLR to 1.5g VS/L day led to a decrease of around 20-28% in SMP. Lower methane yields were obtained when operating at 55°C. The increase in methane production when applying ultrasound to the feed mixtures does not compensate for the energy spent in this pretreatment.
authors: Department of Chemical Engineering and Environmental Technology, University Institute of Technology of Asturias, Campus of Gijon, University of Oviedo, 33203 Gijón, Spain. emara@uniovi.es
authors: E
authors: E
authors: Marañón
authors: L
authors: L
authors: Castrillón
authors: G
authors: G
authors: Quiroga
authors: Y
authors: Y
authors: Fernández-Nava
authors: L
authors: L
authors: Gómez
authors: M M
authors: MM
authors: García
mesh_terms: D000818:Animals; D056804:Biofuels; D002417:Cattle; D005735:Garbage; D008372:Manure; D012722:Sewage; D014465:Ultrasonics
chemical_list: D056804:Biofuels; D008372:Manure; D012722:Sewage