Optimization of Bio‐Methane Synthesis From Biogas Under Wide Operating Loads via Multi‐Steady States

The CO 2 methanation with wide operation loads shows advantages in power‐to‐gas (P2G) technologies using renewable energy. This study establishes a biogas methanation model based on kinetics to study the reactor hotspots and multiple steady states. The results show that heat removal and heat transfer optimization are difficult to avoid the formation of hotspots. Adjusting hydrogen fed into the two reactors and recycling the product gas show the ability to decrease peak temperatures and suppress hotspot formation. Low raw gas pressure makes it difficult to activate the reaction, and a pressure higher than 0.5 MPa is required for methanation activation. When the operation loads of feed biogas and H 2 , namely, the flow compared to baseline condition, range from 5% to 110%, a total conversion higher than 99% and an energy efficiency of approximately 75% are achieved. These results provide a reference for P2G technology with fluctuating renewable energy to meet wide loads.