A new side-looking at the dark fermentation of sugarcane vinasse: Improving the carboxylates production in mesophilic EGSB by selection of the hydraulic retention time and substrate concentration

Author(s)

Bernal, Andressa Picionieri ^[1] ; de Menezes, Camila Aparecida ^[1] ; Silva, Edson Luiz ^[2]

Affiliation

^[1] Univ Sao Paulo, Dept Hydraul & Sanitat, Av Trabalhador Saocarlense 400, BR-400 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Chem Engn, Rod Washington Luis, Km 235, BR-13565905 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: INTERNATIONAL JOURNAL OF HYDROGEN ENERGY; v. 46, n. 24, p. 12758-12770, APR 6 2021.
• Web of Science Citations: 0

Abstract

In recent years, a lot of scientific effort has been put into reusing the energy potential of sugarcane vinasse by dark fermentation. However, the findings so far indicate that new pathways need to be followed. In this context, this study assessed the effect of hydraulic retention time (HRT, from 24 to 1 h) on vinasse fermentation (10, 20, and 30 g COD L-1) in three mesophilic expanded granular sludge bed reactors (EGSB). The carbohydrate conversion remained above 60% at all organic loading rates applied. The maximum hydrogen production rate (8.77 L day(-1) L-1) was obtained for 720 kg COD m(-3) day(-1) and associated to the lactate-acetate pathway. The highest productivities of propionic, acetic, and butyric acids were 3.11, 1.68, and 2.45 g L-1 h(-1), respectively, at a HRT of 1 h. At this HRT, the degrees of acidification remained between 54% and 76% in all EGSB reactors. This research provides insights for carboxylate production from sugarcane vinasse and suggests applying the EGSB setup in the acidogenic stage of two-stage processes. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved. (AU)

• 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