Process considerations and economic evaluation of two-step steam pretreatment for production of fuel ethanol from softwood
(2004) In Biotechnology Progress 20(5). p.1421-1429- Abstract
- To increase the overall ethanol yield from softwood, the steam pretreatment stage can be carried out in two steps. The two-step pretreatment process was evaluated from a techno-economic standpoint and compared with the one-step pretreatment process. The production plants considered were designed to utilize spruce as raw material and have a capacity of 200 000 tons/year. The two-step process resulted in a higher ethanol yield and a lower requirement for enzymes. However, the two-step process is more capital-intensive and has a higher energy requirement. The estimated ethanol production cost was the same, 4.13 SEK/L (55.1 cent/L) for both alternatives. For the two-step process different energy-saving options were considered, such as a higher... (More)
- To increase the overall ethanol yield from softwood, the steam pretreatment stage can be carried out in two steps. The two-step pretreatment process was evaluated from a techno-economic standpoint and compared with the one-step pretreatment process. The production plants considered were designed to utilize spruce as raw material and have a capacity of 200 000 tons/year. The two-step process resulted in a higher ethanol yield and a lower requirement for enzymes. However, the two-step process is more capital-intensive and has a higher energy requirement. The estimated ethanol production cost was the same, 4.13 SEK/L (55.1 cent/L) for both alternatives. For the two-step process different energy-saving options were considered, such as a higher concentration of water-insoluble solids in the filter cake before the second step, and the possibility of excluding the pressure reduction between the steps. The most optimistic configuration, with 50% water-insoluble solids in the filter cake in the feed to the second pretreatment step, no pressure reduction between the pretreatment steps, and 77% overall ethanol yield (0.25 kg EtOH/kg dry wood), resulted in a production cost of 3.90 SEK/L (52.0 cent/L). This shows the potential for the two-step pretreatment process, which, however, remains to be verified in pilot trials. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/138775
- author
- Wingren, Anders LU ; Söderström, Johanna LU ; Galbe, Mats LU and Zacchi, Guido LU
- organization
- publishing date
- 2004
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Biotechnology Progress
- volume
- 20
- issue
- 5
- pages
- 1421 - 1429
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000224377700016
- scopus:5544244645
- ISSN
- 1520-6033
- DOI
- 10.1021/bp049931v
- language
- English
- LU publication?
- yes
- id
- a3f0aec0-bde1-4903-a304-6f0c82f463f6 (old id 138775)
- date added to LUP
- 2016-04-01 16:21:36
- date last changed
- 2023-11-14 09:57:11
@article{a3f0aec0-bde1-4903-a304-6f0c82f463f6, abstract = {{To increase the overall ethanol yield from softwood, the steam pretreatment stage can be carried out in two steps. The two-step pretreatment process was evaluated from a techno-economic standpoint and compared with the one-step pretreatment process. The production plants considered were designed to utilize spruce as raw material and have a capacity of 200 000 tons/year. The two-step process resulted in a higher ethanol yield and a lower requirement for enzymes. However, the two-step process is more capital-intensive and has a higher energy requirement. The estimated ethanol production cost was the same, 4.13 SEK/L (55.1 cent/L) for both alternatives. For the two-step process different energy-saving options were considered, such as a higher concentration of water-insoluble solids in the filter cake before the second step, and the possibility of excluding the pressure reduction between the steps. The most optimistic configuration, with 50% water-insoluble solids in the filter cake in the feed to the second pretreatment step, no pressure reduction between the pretreatment steps, and 77% overall ethanol yield (0.25 kg EtOH/kg dry wood), resulted in a production cost of 3.90 SEK/L (52.0 cent/L). This shows the potential for the two-step pretreatment process, which, however, remains to be verified in pilot trials.}}, author = {{Wingren, Anders and Söderström, Johanna and Galbe, Mats and Zacchi, Guido}}, issn = {{1520-6033}}, language = {{eng}}, number = {{5}}, pages = {{1421--1429}}, publisher = {{The American Chemical Society (ACS)}}, series = {{Biotechnology Progress}}, title = {{Process considerations and economic evaluation of two-step steam pretreatment for production of fuel ethanol from softwood}}, url = {{http://dx.doi.org/10.1021/bp049931v}}, doi = {{10.1021/bp049931v}}, volume = {{20}}, year = {{2004}}, }