Pure hydrogen for fuel cells: A novel design of compact endothermic catalytic steam reformer

The design and the development of a new concept steam reformer for the production of hydrogen from light hydrocarbon gas feedstock with high efficiency and improved life service are presented. Design incorporates a radiant section and a convection section within a single cylindrical furnace vessel. Thank of this new geometry, the flue gas exits from the steam reformer furnace at about 560 degrees C instead of the 980 degrees C released through a conventional design. The reformer consists of a tube regenerative heat exchanger design, so that the final process gas temperature exiting from the reformer tube is only at 530 degrees C instead of 825 degrees C. Moreover, in the new conception, the steam reformer doesn't produce excess steam, with an improved efficiency. A radiant burner is used instead of a burner flame; the distance between the burner and the reformer tubes is less than the one used in a conventional steam reformer, allowing a more compact design. Consequently, the maximum reformer tube wall temperature is low, as the reforming pressure. This system is well adapted with the small-scale generation of gases for fuel-cells applications in the range of 1 to 50 kW. Comparing the characteristics of conventional steam reforming technologies, the experimental results obtained with the described system show a low cost and highly energy efficiency.