Recirculation of process streams in fuel ethanol production from softwood based on simultaneous saccharification and fermentation
(2002) 23rd Symposium on Biotechnology for Fuels and Chemical 98. p.849-861- Abstract
- The effect of process stream recirculation on ethanol production from steam- pretreated softwood based on simultaneous saccharification and fermentation (SSF) was investigated for two process configurations. In the first configuration, a part of the stillage stream after distillation was recycled and, in the second configuration, the liquid after SSF was recycled. The aim was to minimize the energy consumption in the distillation of the fermentation broth and in the evaporation of the stillage, as well as the use of fresh water. However, recirculation leads to an increased concentration of nonvolatiles in the first configuration, and of both volatiles and nonvolatiles in the second configuration. These substances might be inhibitory to the... (More)
- The effect of process stream recirculation on ethanol production from steam- pretreated softwood based on simultaneous saccharification and fermentation (SSF) was investigated for two process configurations. In the first configuration, a part of the stillage stream after distillation was recycled and, in the second configuration, the liquid after SSF was recycled. The aim was to minimize the energy consumption in the distillation of the fermentation broth and in the evaporation of the stillage, as well as the use of fresh water. However, recirculation leads to an increased concentration of nonvolatiles in the first configuration, and of both volatiles and nonvolatiles in the second configuration. These substances might be inhibitory to the enzymes and the yeast in SSF. When 60% of the fresh water was replaced by stillage, the ethanol yield and the productivity were the same as for the configuration without recirculation. The ethanol production cost was reduced by 17%. In the second configuration, up to 40% of the fresh water could be replaced without affecting the final ethanol yield, although the initial ethanol productivity decreased. The ethanol production cost was reduced by 12%. At higher degrees of recirculation,fermentation was clearly inhibited, resulting in a decrease in ethanol yield while hydrolysis seemed unaffected. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/339719
- author
- Alkasrawi, Malek LU ; Galbe, Mats LU and Zacchi, Guido LU
- organization
- publishing date
- 2002
- type
- Chapter in Book/Report/Conference proceeding
- publication status
- published
- subject
- keywords
- recirculation, simultaneous saccharification and fermentation, softwood, inhibition, ethanol
- host publication
- Applied Biochemistry and Biotechnology
- volume
- 98
- pages
- 849 - 861
- publisher
- Humana Press
- conference name
- 23rd Symposium on Biotechnology for Fuels and Chemical
- conference location
- Breckenridge, Colorado, United States
- conference dates
- 2001-05-06 - 2001-05-09
- external identifiers
-
- wos:000175257800073
- scopus:0036237212
- ISSN
- 0273-2289
- 1559-0291
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Chemical Engineering (011001014), Analytical Chemistry (S/LTH) (011001004)
- id
- 9690a751-84a7-475d-8d3d-f34a1e829beb (old id 339719)
- date added to LUP
- 2016-04-01 11:41:58
- date last changed
- 2024-01-07 17:07:23
@inproceedings{9690a751-84a7-475d-8d3d-f34a1e829beb, abstract = {{The effect of process stream recirculation on ethanol production from steam- pretreated softwood based on simultaneous saccharification and fermentation (SSF) was investigated for two process configurations. In the first configuration, a part of the stillage stream after distillation was recycled and, in the second configuration, the liquid after SSF was recycled. The aim was to minimize the energy consumption in the distillation of the fermentation broth and in the evaporation of the stillage, as well as the use of fresh water. However, recirculation leads to an increased concentration of nonvolatiles in the first configuration, and of both volatiles and nonvolatiles in the second configuration. These substances might be inhibitory to the enzymes and the yeast in SSF. When 60% of the fresh water was replaced by stillage, the ethanol yield and the productivity were the same as for the configuration without recirculation. The ethanol production cost was reduced by 17%. In the second configuration, up to 40% of the fresh water could be replaced without affecting the final ethanol yield, although the initial ethanol productivity decreased. The ethanol production cost was reduced by 12%. At higher degrees of recirculation,fermentation was clearly inhibited, resulting in a decrease in ethanol yield while hydrolysis seemed unaffected.}}, author = {{Alkasrawi, Malek and Galbe, Mats and Zacchi, Guido}}, booktitle = {{Applied Biochemistry and Biotechnology}}, issn = {{0273-2289}}, keywords = {{recirculation; simultaneous saccharification and fermentation; softwood; inhibition; ethanol}}, language = {{eng}}, pages = {{849--861}}, publisher = {{Humana Press}}, title = {{Recirculation of process streams in fuel ethanol production from softwood based on simultaneous saccharification and fermentation}}, volume = {{98}}, year = {{2002}}, }