Methane reformer

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A methane refomer is a device used in chemical engineering, which can produce pure hydrogen gas from natural gas using a catalyst. There are two natural gas reformer technologies — autothermal reforming (ATR) and steam methane reforming (SMR). Both methods work by exposing natural gas to a catalyst (usually nickel) at high temperature and pressure.

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[edit] Steam reforming

SMR uses an external source of hot gas to heat tubes in which a catalytic reaction takes place that converts steam and lighter hydrocarbons such as natural gas (methane) or refinery feedstock into hydrogen and carbon monoxide (syngas). Syngas reacts further to give more hydrogen and carbon dioxide in the reactor. The carbon oxides are removed before use by means of pressure swing absorption (PSA) with molecular sieves for the final purification. The PSA works by absorbing all impurities from the syngas stream to leave a pure hydrogen gas.

[edit] Autothermal reforming

ATR burns a portion of the natural gas within the reforming vessel to provide heat for the reaction, which takes place in a single large vessel.

[edit] Advantages and disadvantages

The capital cost of steam reforming plants is prohibitive for small to medium size applications because the technology does not scale down well. Conventional steam reforming plants operate at pressures between 200 and 600 psi with outlet temperatures in the range of 815 to 925 C. However, analyses have shown that even though it is more costly to construct, a well-designed SMR can produce hydrogen more cost-effectively than an ATR.[1]

[edit] See also

[edit] References

  1. ^ http://www.assemblymag.com/CDA/Archives/edabe122ce5c9010VgnVCM100000f932a8c0____

[edit] External links