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Fuel cells require hydrogen in order to operate. Primarily, there are three different ways to provide the hydrogen supply; direct-feed pure hydrogen, renewables and reforming another fuel such as renewable fuel to create hydrogen. Reforming enables the flexibility to use a wide range of fuels such as methanol and ethanol, and hydrocarbon fuels such as natural gas, propane and diesel to produce hydrogen. In the long run, this flexibility is extremely important due to the variety of fuels found locally throughout the world.
IdaTech's fuel processing technology is attractive to industries such as telecommunications and utilities needing on-site hydrogen production for remote sites.
IdaTech's fuel processors are capable of reforming alcohols and hydrocarbons. Though different chemical processes are required for extracting hydrogen, the overall concept behind our fuel processors is similar and straightforward - each including IdaTech's patented purification technology, compact catalytic steam reformer, and fully integrated burner and vaporizer.
Alcohol feedstocks, such as methanol combined with water, are vaporized and fed into a reaction zone. The methanol and water molecules in the vapor catalytically react to form hydrogen, and carbon oxides. This is the steam reformation process.
Hydrocarbon feedstocks require some additional steps in the hydrogen extraction process. Gaseous hydrocarbons such as natural gas and propane include de-sulfurization. First, the fuel is de-sulfurized over an absorbent bed. The de-sulfurized fuel is reformed at design temperature where the hydrogen is then extracted. Conditions are optimized to minimize coking (carbon deposition).
Once produced in the reformation process, the hydrogen gas then enters the purification chamber. There, the hydrogen molecules pass through a palladium-membrane module – IdaTech's Hypurium™ membrane. The membrane rejects unwanted impurities from the product hydrogen stream. The hydrogen is further purified in a catalytic bed and sent to the fuel cell.
The rejected molecules, including CO and CO2 as well as some H2 and unconverted feedstock, are sent back into the combustion chamber, where they are cleanly burned to provide heat to the steam reforming process.
The hydrogen that exits the reformer typically is greater than 99.9% pure with less than one part per million (ppm) carbon monoxide and less than three ppm carbon dioxide, regardless of the choice of feedstock. IdaTech's fuel processors are compact and designed for simple integration. Fuel processing technology is continually improving and the reformers are getting smaller and more efficient. |
