Syngas production from CO₂/CH₄ rich combustion in a porous media burner: Experimental characterization and elementary reaction model

Methane and carbon dioxide are two major components in many biomass-derived gases such as landfill gas and biogas, which are renewable and have potential fuel cell applications. Syngas production from non-catalytic and fuel-rich combustion using a two-layer porous media burner was studied experimentally and numerically with a range of CO₂ content in the CH₄ fuel. With an air flow rate of 5 L/min, an equivalence ratio of 1.5 and a mole ratio of CO₂/CH₄ of 1, the reforming efficiency was found to be 45.3%, larger than that (39.1%) without CO₂ in the feed at the same air flow rate and equivalence ratio. A two-dimensional model with an elementary reaction mechanism was developed to study the influence of carbon dioxide on the reforming characteristics. The model is validated by the experimental results with good agreement. The simulation results clearly showed that the reaction process along the burner could be divided into a preheating zone, a CO₂-consuming zone and a CO₂-generating zone according to the net reaction rate of CO₂.