Experimental and analytical study of a porous media reformer with passive air entrainment

Abstract

A porous media fuel reformer featuring passive air entrainment and a surface-stabilized flame is demonstrated and utilized for the reformation of methane. Passive air entrainment negates the need for auxiliary resources beyond a source of compressed fuel gas for operation, making a reformer of this design promising for applications such as replacement of hydrocarbon flaring with syngas generation at isolated oil and gas production sites and generation of syngas in other remote locations. The porous media reformer design presented in this study incorporates an eductor to entrain ambient air and a swirl mixing chamber and porous media bed to premix fuel and oxidizer before combustion. A range of methane flow rates was tested in this study, and the effect on air entrainment, and therefore equivalence ratio, was examined. A wide range of stable operating conditions shows a large turndown ratio of the reformer and burning rate ratios greater than unity. Fuel conversion efficiency and syngas production were evaluated and concentrations of methane, hydrogen, carbon monoxide and carbon dioxide are presented for a range of methane flow rates. Product compositions are compared to equilibrium and a high extent of fuel conversion efficiency is shown. An analytical model that accounts for reformer geometry and operating conditions to predict air entrainment and equivalence ratio is presented and compared with the experimental results. The analytical model compares favorably with the experimental results and can guide future reformer development and scaling.