Critical factors affecting the integration of biomass gasification and syngas fermentation technology

Karthikeyan D. Ramachandriya; Dimple K. Kundiyana; Ashokkumar M. Sharma; Ajay Kumar; Hasan K. Atiyeh; Raymond L. Huhnke; Mark R. Wilkins; Karthikeyan D. Ramachandriya; Dimple K. Kundiyana; Ashokkumar M. Sharma; Ajay Kumar; Hasan K. Atiyeh; Raymond L. Huhnke; Mark R. Wilkins

doi:10.3934/bioeng.2016.2.188

AIMS Bioengineering

2016, Volume 3, Issue 2: 188-210. doi: 10.3934/bioeng.2016.2.188

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Review

Critical factors affecting the integration of biomass gasification and syngas fermentation technology

1.
Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK, USA
2.
E&J Gallo, Modesto, CA, USA
3.
Bioeconomy Institute, Iowa State University, Ames, IA, USA

Received: 05 April 2016 Accepted: 15 May 2016 Published: 17 May 2016

Gasification-fermentation is a thermochemical-biological platform for the production of fuels and chemicals. Biomass is gasified at high temperatures to make syngas, a gas composed of CO, CO₂, H₂, N₂ and other minor components. Syngas is then fed to anaerobic microorganisms that convert CO, CO₂and H₂ to alcohols by fermentation. This platform offers numerous advantages such as flexibility of feedstock and syngas composition and lower operating temperature and pressure compared to other catalytic syngas conversion processes. In comparison to hydrolysis-fermentation, gasification-fermentation has a major advantage of utilizing all organic components of biomass, including lignin, to yield higher fuel production. Furthermore, syngas fermentation microorganisms do not require strict CO:H₂:CO₂ratios, hence gas reforming is not required. However, several issues must be addressed for successful deployment of gasification-fermentation, particularly those that involve the integration of gasification and fermentation. Most previous reviews have focused only on either biomass gasification or syngas fermentation. In this review, the critical factors that affect the integration of biomass gasification with syngas fermentation, such as carbon conversion efficiency, effect of trace gaseous species, H₂ to CO ratio requirements, and microbial preference of carbon substrate, are thoroughly discussed.
- bioenergy,
- alcohol fuels,
- lignocellulosic biomass,
- acetogens,
- acetyl-CoA pathway
Citation: Karthikeyan D. Ramachandriya, Dimple K. Kundiyana, Ashokkumar M. Sharma, Ajay Kumar, Hasan K. Atiyeh, Raymond L. Huhnke, Mark R. Wilkins. Critical factors affecting the integration of biomass gasification and syngas fermentation technology[J]. AIMS Bioengineering, 2016, 3(2): 188-210. doi: 10.3934/bioeng.2016.2.188

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Abstract

Gasification-fermentation is a thermochemical-biological platform for the production of fuels and chemicals. Biomass is gasified at high temperatures to make syngas, a gas composed of CO, CO₂, H₂, N₂ and other minor components. Syngas is then fed to anaerobic microorganisms that convert CO, CO₂and H₂ to alcohols by fermentation. This platform offers numerous advantages such as flexibility of feedstock and syngas composition and lower operating temperature and pressure compared to other catalytic syngas conversion processes. In comparison to hydrolysis-fermentation, gasification-fermentation has a major advantage of utilizing all organic components of biomass, including lignin, to yield higher fuel production. Furthermore, syngas fermentation microorganisms do not require strict CO:H₂:CO₂ratios, hence gas reforming is not required. However, several issues must be addressed for successful deployment of gasification-fermentation, particularly those that involve the integration of gasification and fermentation. Most previous reviews have focused only on either biomass gasification or syngas fermentation. In this review, the critical factors that affect the integration of biomass gasification with syngas fermentation, such as carbon conversion efficiency, effect of trace gaseous species, H₂ to CO ratio requirements, and microbial preference of carbon substrate, are thoroughly discussed.

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