Novel insights on the versatility of biohydrogen production from sugarcane vinasse via thermophilic dark fermentation: Impacts of pH-driven operating strategies on acidogenesis metabolite profiles

Author(s)

Fuess, Lucas Tadeu ^{[1, 2]} ; Zaiat, Marcelo ^[1] ; Oller do Nascimento, Claudio Augusto ^[2]

Affiliation

^[1] Univ Sao Paulo LPB EESC USP, Sao Carlos Sch Engn, Biol Proc Lab, Ave Joao Dagnone 1100, BR-13563120 Sao Carlos, SP - Brazil

^[2] Univ Sao Paulo DEQ EP USP, Polytech Sch, Dept Chem Engn, Ave Prof Lineu Prestes 580, Bloco 18 Conjunto Quim, BR-05508000 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: Bioresource Technology; v. 286, AUG 2019.
• Web of Science Citations: 3

Abstract

An innovative application of the anaerobic structured-bed reactor (AnSTBR) in thermophilic dark fermentation of sugarcane vinasse targeting biohydrogen (bioH(2)) production was assessed. A detailed metabolite monitoring program identified the major substrates and primary metabolic pathways within the system. Increasing the applied organic loading rate positively affected bioH(2) production, reaching 2074 N mL-H-2 L-1 d(-1) and indicating an optimal load of approximately 70 kg-COD m(-3) d(-1). Controlling the fermentation pH (5.0-5.5) was the primary strategy to maintain bioH(2)-producing conditions, offsetting negative impacts associated with the compositional variability of vinasse. Metabolic correlations pointed out lactate as the primary substrate for bioH(2) production, indicating its accumulation as evidence of impaired reactors. The versatility of the acidogenic system was confirmed by identifying three major metabolic pathways according to the pH, i.e., lactate-producing (pH < 5.0), bioH(2)-/butyrate-producing (pH = 5.0-5.5) and bioH(2)-producing/sulfate-reducing (pH > 6.0) systems, which enables managing the operation of the reactors for diversified purposes in practical aspects. (AU)

• FAPESP's process: 15/50684-9 - Sustainable gas pathways for Brazil: from microcosm to macrocosm
• Grantee: Reinaldo Giudici
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/00080-5 - Enhancement of energy production from sugarcane in first generation biorefineries: biodigestion as the core conversion step
• Grantee: Lucas Tadeu Fuess
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/06246-7 - Biorefinery concept applied to biological wastewater treatment plants: environmental pollution control coupled with material and energy recovery
• Grantee: Marcelo Zaiat
• Support Opportunities: Research Projects - Thematic Grants