Document Type: Research Paper
Centro de Investigación y Transferencia en Ingeniería Química Ambiental (CIQA), Facultad Regional Córdoba, Universidad Tecnológica Nacional, Maestro López esq. Cruz Roja Argentina, 5016 Córdoba, Argentina.
Centro de Investigación en Nanociencia y Nanotecnología (NANOTEC), Facultad Regional Córdoba, Universidad Tecnológica Nacional, Maestro López esq. Cruz Roja Argentina, 5016 Córdoba, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, C1425FQB Buenos Aires, Argentina.
This study reports for the ﬁrst time on biohydrogen production by dark fermentation using a novel combination of mild heat-pretreated fruit and vegetable waste (FVW) as raw material and vermicompost as an economical source of hydrogen-producing bacteria. A suspension rich in reducing sugars obtained from FVW was used at different initial concentrations (5 to 25 g reducing sugars/L) during the bioprocess conducted in batch reactors at mesophilic temperature of 35 °C. The use of a mild heat-pretreated substrate and the consequent elimination of the natural microbiota present in the FVW led to higher hydrogen production than the control. Clostridium species, hydrogen-producing bacteria via butyric acid fermentation pathway, were the dominant microorganisms in the bioprocess. Hydrogen production, volumetric hydrogen production rate, and pretreated substrate degradation efficiency (63.0 mL/g VS, 372.6 mL/L/d, and 50% BOD5, respectively) obtained in the experiments performed with the highest substrate concentration demonstrated that the developed bioprocess was promising simultaneously leading to high hydrogen contents in biogas and high substrate removal efficiencies.
- Fruit and vegetable waste can be used as low-cost substrate for biohydrogen production.
- Vermicompost was used as novel source of hydrogen-producing bacteria.
- Use of mild heat-pretreated FVW substrate markedly enhanced biohydrogen yield.
- Clostridium species were the dominant microorganisms in the bioprocess.
- Biohydrogen production through FVW valorization using the developed process was found promising.