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Intensification of lignocellulosic bioethanol production process using continuous double-staged immersed membrane
A Mahboubi1, C Uwineza2, W Doyen3
1Swedish Centre for Resource Recovery, University of Borås, 501 90 Borås, Sweden; Flemish Institute for Technological Research, VITO NV, Boeretang 200, B-2400 Mol, Belgium.
Bioresource Technology
|November 1, 2019
Summary
Immersed membrane bioreactors (iMBRs) improve lignocellulosic bioethanol production by overcoming hydrolysis and fermentation challenges. This technology enables stable, continuous processing and efficient separation of solids and cells, enhancing overall efficiency.
Area of Science:
- Biotechnology
- Chemical Engineering
- Renewable Energy
Background:
- Lignocellulosic bioethanol production faces challenges in hydrolysis and fermentation stages, limiting commercial viability.
- Current processes often struggle with efficient solid-liquid separation and byproduct removal.
Purpose of the Study:
- To integrate immersed membrane bioreactors (iMBRs) into lignocellulosic bioethanol production to address processing complexities.
- To evaluate the performance of iMBRs in continuous saccharification-filtration and co-fermentation-filtration of wheat straw.
Main Methods:
- Utilized a double-staged continuous system employing iMBRs for wheat straw slurry.
- Operated at filtration fluxes up to 51.0 LMH, monitoring hydrolysis-filtration and fermentation-filtration stability.
- Investigated the impact of filtration flux, medium quality, and backwashing on membrane fouling and cake formation.
Main Results:
- Achieved stable, long-term continuous operation for 264 hours.
- Demonstrated effective separation of lignin-rich solids (up to 70% lignin) and yeast cells.
- Observed exceptional filtration performance at 21.9 LMH with minimal fouling issues.
Conclusions:
- iMBRs offer significant process intensification potential for lignocellulosic bioethanol production.
- The integrated system effectively tackles technical obstacles in hydrolysis and fermentation.
- This approach enhances the efficiency and commercial feasibility of bioethanol production from lignocellulosic biomass.
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