|Generic hydrogen flow within the system, with different embodiments.|
Nanomix, a nanotechnology company specializing in nanoelectronic sensors for industrial and biomedical applications, has added a sixth patent in its portfolio of cryosorptive hydrogen storage technologies. (Earlier post.)
Nanomix is developing new nanostructured materials that permit the non-chemically-bound low-pressure storage of hydrogen in a medium consisting of solid boron oxide and compounds closely related to it. Its system employs a combination of thermal insulation and an enclosure for the storage and controlled distribution of hydrogen.
Cryogenic storage can be done at 80 K (-193º C, or -316º F), a temperature higher than that required for liquid hydrogen storage (about 23 K, or -250º C). Hydrogen can sorb to surfaces in the activated carbon and can be released by increasing the temperature.
The latest patent pertains specifically to the apparatus and method for operating the storage system that contains the porous storage medium.
Nanomix envisions that, in receiving hydrogen from the distribution chain, its cryosorptive storage tank will be taking in hydrogen from an intermediary, or first tank. The system is flexible as to whether the hydrogen arrives to the first tank via a liquid, gas, or chemical or metal hydride.
Some embodiments of the system may compress and cool the hydrogen prior to entering the first tank, others may do on exiting the first tank, still others may do both. The common requirement is that the hydrogen is cold and pressurized upon entry into the cryosorptive storage tank.
The cryosorptive tank itself contains an insulated pressure chamber with a cold enclosure (Dewar flask); the Dewar flask contains the porous hydrogen storage medium, and is fitted with all connections and equipment necessary to enable its operation.
The operating pressure range of the vessel is typically about 10 to about 30 bar, but can include a larger pressure range of between about 1 bar and up to 50 bar or higher.
At the outset of a fuel release, the cryosorptive hydrogen storage apparatus contains cold, pressurized hydrogen. Release of hydrogen from the storage apparatus is a process that consumes heat, thereby drawing down both the temperature and pressure. Heat can be provided to the cryosorptive storage apparatus by various direct approaches, or through the influx of warm, recycled hydrogen.
The hydrogen storage and release apparatus contains a recycle loop, which warms a portion of the effluxing hydrogen, and returns it to the storage apparatus, thereby maintaining pressure and temperature conditions that support continued hydrogen desorption from the storage medium.
Nanomix is currently seeking industrial partners for the continued development of its hydrogen systems, according to David Macdonald, President and CEO of Nanomix.
US Patent #7,036,324: Hydrogen storage and supply system