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Title: Combined algal processing: A novel integrated biorefinery process to produce algal biofuels and bioproducts

Journal Article · · Algal Research

Here, the development of an integrated biorefinery process capable of producing multiple products is crucial for commercialization of microalgal biofuel production. Dilute acid pretreatment has been demonstrated as an efficient approach to utilize algal biomass more fully, by hydrolyzing microalgal carbohydrates into fermentable sugars, while making the lipids more extractable, and a protein fraction available for other products. Previously, we have shown that sugar-rich liquor could be separated from solid residue by solid-liquid separation (SLS) to produce ethanol via fermentation. However, process modeling has revealed that approximately 37% of the soluble sugars were lost in the solid cake after the SLS. Herein, a Combined Algal Processing (CAP) approach with a simplified configuration has been developed to improve the total energy yield. In CAP, whole algal slurry after acid pretreatment is directly used for ethanol fermentation. The ethanol and microalgal lipids can be sequentially recovered from the fermentation broth by thermal treatment and solvent extraction. Almost all the monomeric fermentable sugars can be utilized for ethanol production without compromising the lipid recovery. The techno-economic analysis (TEA) indicates that the CAP can reduce microalgal biofuel cost by $0.95 per gallon gasoline equivalent (GGE), which is a 9% reduction compared to the previous biorefinery scenario.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Sustainable Transportation Office. Bioenergy Technologies Office
Grant/Contract Number:
AC36-08GO28308
OSTI ID:
1234982
Alternate ID(s):
OSTI ID: 1330940
Report Number(s):
NREL/JA-5100-64979; S2211926415301351; PII: S2211926415301351
Journal Information:
Algal Research, Journal Name: Algal Research Vol. 19 Journal Issue: C; ISSN 2211-9264
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 125 works
Citation information provided by
Web of Science

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