A methodology for optimising feed composition for anaerobic co-digestion of agro-industrial wastes

• Published in: Bioresource technology Vol. 101; no. 4; pp. 1153 - 1158
• Main Authors: Álvarez, J.A., Otero, L., Lema, J.M.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.02.2010; [New York, NY]: Elsevier Ltd; Elsevier
• Subjects: agricultural industry; Agriculture; Agronomy. Soil science and plant productions; Anaerobic co-digestion; anaerobic digestion; Anaerobiosis; Animals; Applied sciences; Batch assay; biodegradation; Biodegradation, Environmental; Biodiesel; Biofuels - analysis; biogas; Biological and medical sciences; Biological treatment of sewage sludges and wastes; biomass; Bioreactors; Biotechnology; Blends; Environment and pollution; Exact sciences and technology; Fish; fish waste; Fishes; food processing wastes; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Industrial applications and implications. Economical aspects; Industrial Waste - analysis; industrial wastes; Kinetics; Linear programming; Manure; Manure - analysis; Methane; Methane - analysis; methane production; Optimization; Organic waste; pig manure; Pollution; Refuse Disposal - methods; renewable energy sources; Sus scrofa; Thunnus; tuna; Use of agricultural and forest wastes. Biomass use, bioconversion; Wastes; Anaerobic co-digestion; Organic waste; Linear programming; Batch assay; Industrial waste; Agricultural industry; Agricultural waste; Anaerobic digestion; Optimization
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2009.09.061

An optimisation protocol for maximising methane production by anaerobic co-digestion of several wastes was carried out. A linear programming method was utilised to set up different blends aimed at maximising the total substrate biodegradation potential (L CH 4/kg substrate) or the biokinetic potential (L CH 4/kg substrate d). In order to validate the process, three agro-industrial wastes were considered: pig manure, tuna fish waste and biodiesel waste, and the results obtained were validated by experimental studies in discontinuous assays. The highest biodegradation potential (321 L CH 4/kg COD) was reached with a mixture composed of 84% pig manure, 5% fish waste and 11% biodiesel waste, while the highest methane production rate (16.4 L CH 4/kg COD d) was obtained by a mixture containing 88% pig manure, 4% fish waste and 8% biodiesel waste. Linear programming was proved to be a powerful, useful and easy-to-use tool to estimate methane production in co-digestion units where different substrates can be fed.