The influence of total solids content and initial pH on batch biohydrogen production by solid substrate fermentation of agroindustrial wastes

• Published in: Journal of environmental management 2013-10, Vol.128, p.126-137
• Main Authors: Robledo-Narváez, Paula N., Muñoz-Páez, Karla M., Poggi-Varaldo, Hector M., Ríos-Leal, Elvira, Calva-Calva, Graciano, Ortega-Clemente, L. Alfredo, Rinderknecht-Seijas, Noemí, Estrada-Vázquez, Carlos, Ponce-Noyola, M. Teresa, Salazar-Montoya, J. Alfredo
• Format: Article
• Language: English
• Subjects: Acidity; activated sludge; Agricultural wastes; Agriculture; Alternative fuels. Production and utilization; Animal, plant and microbial ecology; Applied ecology; Applied sciences; Batch dark fermentation; batch fermentation; Beverages; Biofuels; biohydrogen; Biological; Biological and medical sciences; biological production; biorefining; Conservation, protection and management of environment and wildlife; Energy; Environment management; Exact sciences and technology; Fermentation; Flushing; Fruit; fruit juices; fruit peels; Fruits; Fuels; Fundamental and applied biological sciences. Psychology; General aspects; Hydrogen; Hydrogen - metabolism; hydrogen production; Hydrogen-Ion Concentration; Industrial Waste - analysis; Industrial wastes; juice industry; Mexico; Municipal solid waste; nitrogen; organic matter; organic wastes; pineapples; Refuse Disposal - methods; renewable energy sources; Response surfaces; solid state fermentation; sugarcane bagasse; Total solids; Waste disposal; Wastes
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2013.04.042

Hydrogen is a valuable clean energy source, and its production by biological processes is attractive and environmentally sound and friendly. In México 5 million tons/yr of agroindustrial wastes are generated; these residues are rich in fermentable organic matter that can be used for hydrogen production. On the other hand, batch, intermittently vented, solid substrate fermentation of organic waste has attracted interest in the last 10 years. Thus the objective of our work was to determine the effect of initial total solids content and initial pH on H2 production in batch fermentation of a substrate that consisted of a mixture of sugarcane bagasse, pineapple peelings, and waste activated sludge. The experiment was a response surface based on 22 factorial with central and axial points with initial TS (15–35%) and initial pH (6.5–7.5) as factors. Fermentation was carried out at 35 °C, with intermittent venting of minireactors and periodic flushing with inert N2 gas. Up to 5 cycles of H2 production were observed; the best treatment in our work showed cumulative H2 productions (ca. 3 mmol H2/gds) with 18% and 6.65 initial TS and pH, respectively. There was a significant effect of TS on production of hydrogen, the latter decreased with initial TS increase from 18% onwards. Cumulative H2 productions achieved in this work were higher than those reported for organic fraction of municipal solid waste (OFMSW) and mixtures of OFMSW and fruit peels waste from fruit juice industry, using the same process. Specific energetic potential due to H2 in our work was attractive and fell in the high side of the range of reported results in the open literature. Batch dark fermentation of agrowastes as practiced in our work could be useful for future biorefineries that generate biohydrogen as a first step and could influence the management of this type of agricultural wastes in México and other countries and regions as well. •A mixture of agricultural wastes was batch fermented for bioH2 production.•We evaluated the effect of initial total solids and pH on bioH2 generation.•Response surface analysis revealed an optimum of 3 mmol H2/gds at 18% TS and pH 6.65.•H2 energetic potential was in the high side of the range reported in the literature.•Our results could change agro waste management in terms of H2 and biorefinery.