"Biomethanation of syngas by enriched mixed anaerobic consortium in pressurized agitated column"

J Figueras; H Benbelkacem; C Dumas; P Buffiere

doi:10.1016/j.biortech.2021.125548

"Biomethanation of syngas by enriched mixed anaerobic consortium in pressurized agitated column"

Bioresour Technol. 2021 Oct:338:125548. doi: 10.1016/j.biortech.2021.125548. Epub 2021 Jul 14.

Authors

J Figueras¹, H Benbelkacem¹, C Dumas², P Buffiere³

Affiliations

¹ Univ Lyon, INSA Lyon, DEEP, EA7429, 69621 Villeurbanne, France.
² TBI, University of Toulouse, INSA, INRAE, CNRS, Toulouse, France.
³ Univ Lyon, INSA Lyon, DEEP, EA7429, 69621 Villeurbanne, France. Electronic address: pierre.buffiere@insa-lyon.fr.

PMID: 34284292
DOI: 10.1016/j.biortech.2021.125548

Abstract

In a circular economy approach, heterogeneous wastes can be upgraded to energy in the form of syngas via pyrogasification, and then to methane via biomethanation. Working at high pressure is a promising approach to intensify the process and to reduce gas-liquid transfer limitations. However, raising the pressure could lead to reaching the CO inhibition threshold of the microorganisms involved in syngas-biomethanation. To investigate the impact on pressure on the process, a 10L continuous stirred tank reactor working at 4 bars and 55 °C was implemented. Syngas (40% CO, 40% H₂, 20% CO₂) biomethanation was performed successfully and methane productivity as high as 6.8 mmol_CH4/L_reactor/h with almost full conversion of CO (97%) and H₂ (98%) was achieved. CO inhibition was investigated and carboxydotrophs appeared less resistant to high CO exposition than methanogens.

Keywords: Biological water–gas shift; Biomethanation; Carbon monoxide conversion; Fermentation; Syngas.

MeSH terms

Anaerobiosis
Bioreactors*
Methane
Sewage*

Substances

Sewage
Methane