Effects of H2:CO2 ratio and H2 supply fluctuation on methane content and microbial community composition during in-situ biological biogas upgrading

Abstract

Our research demonstrates that the H₂:CO₂ ratio has a significant effect on reactor performance during in situ biological methanation. Consequently, the H₂:CO₂ molar ratio should be kept at 4:1 to avoid process instability. A shift toward hydrogenotrophic methanogenesis was indicated by an increase in the abundance of the obligate hydrogenotrophic methanogen <i>Methanobacterium</i>.