A Compact and Efficient Steam Methane Reformer for Hydrogen Production

A small-scale steam-methane reforming system for localized, distributed production of hydrogen offers improved performance and lower cost by integrating the following technologies developed at the University of Houston;
(1) Catalyzed steam-methane reforming on ceramic foam catalyst substrates. (2) Coupling of reformers to remote heat sources via heat pipes instead of heating by direct-fired heaters. (3) Catalytic combustion of methane with air on ceramic foam substrates as the heat source. Each of these three technologies confer benefits improving the efficiency, reliability, or cost of an integrated compact steam-methane reforming system.
A prior 2-D computer model was adapted from existing FORTRAN code for a packed-bed reactor and successfully updated to better reflect heat transfer in the ceramic foam bed and at the reactor wall, then validated with experimental heat transfer and reaction data for use in designing commercial-scale ceramic foam catalytic reactors. Different configurations and sizes of both reformer and combustor reactors were studied to arrive at a best configuration for an integrated system. The radial and axial conversions and temperatures of each reactor were studied to match the heat recovery capability of the reformer to the heat generation characteristics of the combustor.
The vetted computer model was used to size and specify a 500 kg/day hydrogen production unit featuring ceramic foam catalyst beds integrated into heat pipe reactors that can be used for multiple end users, ranging from small edible fats and oils hydrogenators to consumer point of sale hydrogen fueling stations. The estimated investment for this 500 kg/day system is $2,286,069 but is expected to drop to less than $1,048,000 using mass production methods. Economic analysis of the 500 kg/day hydrogen production system shows that it is not presently competitive with gasoline as a transportation fuel, but the system is still economically attractive to stationary fuel cell applications or small chemical users with a delivered hydrogen price as low as $1.49/kg, even with a 10% IRR that includes investment recovery, depreciation, taxes, etc.