Enhancing hydrogen production for fuel cell vehicles by superposition of acoustic fields on the reformer: a preliminary study

Because of recent interest in energy efficiency and environmental issues, fuel cell vehicles are seen by many to be the way of the future. As near term fuel cell vehicles will likely use the existing liquid fuel infrastructure, the efficient reformation of hydrocarbon fuels is one technological hurdle that must addressed. An investigation has been made into the possibility of enhancing reformation processes through superposition of an acoustic field on the catalyst bed of a methanol steam reformer. As part of this study, background is given outlining the difficulties and liabilities of steam-reformation for transportation applications. Proven acoustic enhancement of various processes is reviewed and theory of acoustic enhancement of the steam-reforming process is developed. The facility studied includes a steam-reforming reactor that has been modified to accept an acoustic field. Relevant parameters of the acoustic field are quantified and discussed. The effect of the acoustic field has been investigated with relation to the reactor output parameters. Although the facility used has not been optimized for utilizing acoustic waves, significant acoustic enhancement of the steam-reformation process is demonstrated by the study and such enhancement has shown a positive effect on the reformation process. Potential benefits insulting from acoustic enhancement of steam reforming as shown by this study are: an increased reactor capacity for a given size and mass, smoothing of the temperature profile and better control of the temperatures in the catalyst bed. It is expected that for different fuels and/or reforming methods, similar results would be obtained for comparable process constraints.