Oxidation of natural gas, natural gas/syngas mixtures, and effect of burnt gas recirculation: Experimental and detailed kinetic modeling

The oxidation of methane-based fuels was studied experimentally in a fused-silica jet-stirred reactor (JSR) operating at 1-10 atm, over the temperature range of 900-1450 K, from fuel-lean to fuel-rich conditions. Similar experiments were performed in the presence of carbon dioxide or syngas (CO/H(2)). A previously proposed kinetic reaction mechanism updated for modeling the oxidation of hydrogen, CO, methane, methanol, formaldehyde, and natural gas over a wide range of conditions including JSR, flame, shock tube, and plug flow reactor was used. A detailed chemical kinetic modeling of the present experiments was performed yielding a good agreement between the modeling, the present data and literature burning velocities, and ignition data. Reaction path analyses were used to delineate the important reactions influencing the kinetic of oxidation of the fuels in the presence of variable amounts of CO(2). The kinetic reaction scheme proposed helps understand the effect of the additives on the oxidation of methane.