Thermodynamic Analysis of Low Temperature Methane Wet-Air Reforming in a Microcombustor

We studied the effects of reaction pressure, molar ratios of air to methane and steam to methane on the reforming process at temperatures below 973 K theoretically. Their reasonable ranges were also studied. We also compared the performance of a methane autothermal reforming system and a non-oxygen system. Results show that methane autothermal reforming occurs much more easily at temperatures above 633 K, reaction pressures below 0.10 MPa, a molar ratio of air to methane of 2.0, and a molar ratio of steam to methane between 1.0 and 2.5. At a definite methane mass flow, a higher methane conversion rate and hydrogen yield can be obtained at lower temperatures and in lesser steam to methane ratio in an autothermal reforming system compared with a non-oxygen system.