| Περίληψη: | This investigation comprises a contribution on the production of a new generation biofuel using the
industrial liquid waste of bioethanol distilleries, known as vinasse. This study focuses on the exploitation of vinasse
as an acidogenesis substrate for volatile fatty acids and simultaneous ethanol production. These products can be
used for ester production, which is the new generation biofuel. Therefore, the aims of the present study are (i) to
examine any promotional effect of γ-alumina on acidogenesis of a sucrose-raffinose mixture simulating vinasse,
(ii) to study the operational stability of the continuous acidogenesis of sucrose and raffinose and subsequently of
vinasse, and (iii) to determine the volatile fatty acid chemical composition and ethanol formation.
Results: Batch acidogenesis of sucrose and raffinose mixtures showed that γ-alumina promoted fermentation leading to
an increase in the volatile fatty acid yield factor from 40% to 95% compared to free cells. The application of the system in
continuous mode for more than 3 months showed that the continuous volatile fatty acid productivity obtained was
higher than 7 g/L/day. Lactic acid was the predominant acid when sucrose and raffinose were used while butyric acid in
the case of vinasse. The highest volatile fatty acid concentration reached was 19 g/L for vinasse.
Conclusions: A promoting effect of γ-alumina in acidogenic fermentation of sucrose-raffinose and vinasse is reported.
Continuous acidogenesis of sucrose-raffinose mixtures and vinasse using γ-alumina with immobilized cells showed high
operational stability (more than 3 months). These findings result in easy scale up of the process that will produce a high
annual added value of $11,000,000 in a daily bioethanol production plant of 50,000 L.
|
|---|
