MRT™’s Pure Hydrogen
integrated hydrogen generation system includes all equipment required
to convert as-supplied natural gas to pure, pressurized hydrogen.
Natural gas is conditioned by sulfur removal, compression and
preheating before feeding to the single step membrane reactor. A
combination pre-heater, using reactor off gas as fuel, also raises the
steam needed for the reforming reaction. The heart of the system is the
membrane reactor where the natural gas and steam mix intimately with
catalyst in a fluidized bed, ensuring optimum heat and mass transfer
conditions. Perm-selective membranes within the reactor continuously
withdraw pure hydrogen driving the equilibrium forward and maximizing
the yield of hydrogen from the natural gas feed. Optimized internal
oxidation provides additional energy to drive the reaction. Heat
integration is maximized to recover energy. Compressors within the
system for natural gas, air and hydrogen are selected based on the
available supplies and to meet the needs of the end-user.
The system is designed for automated, unattended operation with key
parameters monitored and controlled and for fail-safe operation by an
on-board controller. The unit is designed for compactness and ease of
access and is delivered on a self-contained, enclosed skid.
Membranes are the key
Membranes are the key to MRT™’s success in developing simple,
cost-effective processes for making pure hydrogen. Whether in
Fluid Bed Membrane Reformers or in HydRec™ hydrogen purifiers
recovery units, MRT™ can draw on a broad range of membrane thicknesses
and compositions to suit a variety of applications.
MRT™ has advanced the science and practical aspects of using metallic
membranes for hydrogen separation. Thin films of
Palladium-containing alloys demonstrate unique properties when it comes
to hydrogen. Hydrogen molecules dissociate on the membrane
surface and, as individual atoms, diffuse through the membrane film
under a pressure and concentration gradient. Pure hydrogen
molecules then re-associate on the inside surface and are drawn
away. Providing the membrane is intact, nothing else passes
through, resulting in extremely high selectivity for hydrogen and the
capability to produce hydrogen of 99.999% purity and beyond.
Membranes are manufactured either as rolled foils or as deposited thin
films. While Palladium-based foils of common compositions are
available commercially, MRT™ has developed its own alloy compositions
for added performance and robustness. In addition, a
patent-pending bonding technique has been developed to permanently
attach membranes to support modules with a perfect, hydrogen-tight seal.
For membranes thinner than 15 microns, MRT™ uses a proprietary coating
technique. Prototype membranes as thin as 8 microns have been
produced and show excellent performance and longevity.