Advanced

Effect of washing on yield in one- and two-step steam pretreatment of softwood for production of ethanol

Söderström, Johanna LU ; Galbe, Mats LU and Zacchi, Guido LU (2004) In Biotechnology Progress 20(3). p.744-749
Abstract
Two-step steam pretreatment of softwood on laboratory scale has previously been shown to result in higher yields than one-step steam pretreatment. In this study, these results are verified on a larger scale. In an industrial process filtration and washing of the material between the two pretreatment steps are difficult without release of pressure. A worst case without filtration or washing was thus investigated to determine the influence of poor washing on the yield of sugars and the formation of byproducts. Steam pretreatment with SO2 impregnation was investigated using three different procedures. One-step steam pretreatment was performed at 215 degreesC for 5 min. Two different kinds of two-step steam pretreatment were performed at 190... (More)
Two-step steam pretreatment of softwood on laboratory scale has previously been shown to result in higher yields than one-step steam pretreatment. In this study, these results are verified on a larger scale. In an industrial process filtration and washing of the material between the two pretreatment steps are difficult without release of pressure. A worst case without filtration or washing was thus investigated to determine the influence of poor washing on the yield of sugars and the formation of byproducts. Steam pretreatment with SO2 impregnation was investigated using three different procedures. One-step steam pretreatment was performed at 215 degreesC for 5 min. Two different kinds of two-step steam pretreatment were performed at 190 degreesC for 2 min in the first step and at 210 degreesC for 5 min in the second step. In one case the slurry obtained after the first pretreatment step was separated into a liquid and a solid phase, where the water-insoluble solid material was washed with water and then used for pretreatment in the second step. In the other case of two-step steam pretreatment, neither separation nor washing was performed. The pretreated material was evaluated using both enzymatic hydrolysis and fed-batch simultaneous saccharification and fermentation. Both two-step steam pretreatment process configurations investigated resulted in higher yields of ethanol (300 L/ton) than one-step steam pretreatment (227 L/ton). Separation and washing of the material between the pretreatment steps in the two-step steam pretreatment process did not improve the overall sugar yield, although the formation of sugar degradation products was reduced. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Biotechnology Progress
volume
20
issue
3
pages
744 - 749
publisher
The American Chemical Society
external identifiers
  • wos:000221841800014
  • scopus:2942700402
ISSN
1520-6033
DOI
10.1021/bp034353o
language
English
LU publication?
yes
id
220bd5bf-ec20-4a8a-93b2-db156819af8a (old id 138826)
date added to LUP
2007-06-25 16:02:06
date last changed
2017-01-01 06:53:06
@article{220bd5bf-ec20-4a8a-93b2-db156819af8a,
  abstract     = {Two-step steam pretreatment of softwood on laboratory scale has previously been shown to result in higher yields than one-step steam pretreatment. In this study, these results are verified on a larger scale. In an industrial process filtration and washing of the material between the two pretreatment steps are difficult without release of pressure. A worst case without filtration or washing was thus investigated to determine the influence of poor washing on the yield of sugars and the formation of byproducts. Steam pretreatment with SO2 impregnation was investigated using three different procedures. One-step steam pretreatment was performed at 215 degreesC for 5 min. Two different kinds of two-step steam pretreatment were performed at 190 degreesC for 2 min in the first step and at 210 degreesC for 5 min in the second step. In one case the slurry obtained after the first pretreatment step was separated into a liquid and a solid phase, where the water-insoluble solid material was washed with water and then used for pretreatment in the second step. In the other case of two-step steam pretreatment, neither separation nor washing was performed. The pretreated material was evaluated using both enzymatic hydrolysis and fed-batch simultaneous saccharification and fermentation. Both two-step steam pretreatment process configurations investigated resulted in higher yields of ethanol (300 L/ton) than one-step steam pretreatment (227 L/ton). Separation and washing of the material between the pretreatment steps in the two-step steam pretreatment process did not improve the overall sugar yield, although the formation of sugar degradation products was reduced.},
  author       = {Söderström, Johanna and Galbe, Mats and Zacchi, Guido},
  issn         = {1520-6033},
  language     = {eng},
  number       = {3},
  pages        = {744--749},
  publisher    = {The American Chemical Society},
  series       = {Biotechnology Progress},
  title        = {Effect of washing on yield in one- and two-step steam pretreatment of softwood for production of ethanol},
  url          = {http://dx.doi.org/10.1021/bp034353o},
  volume       = {20},
  year         = {2004},
}