Methane fuel reforming

In a typical PAFC system, methane passes through a reformer with steam from the coolant loop of the water-cooled fuel cell. Heat for the reforming reaction is generated by combusting the depleted fuel. The reformed natural gas contains typically 60 percent H9, 20 percent CO, and 20 percent H9O. Because the platinum catalyst in the PAFC can tolerate only about 0.5 percent CO, this fuel mixture is passed through a water gas shift reactor before being fed to the fuel cell. 

The analysis showed, with various "value adders" (e.g., oxygen sales and carbon-emission-offset credits), the cost of wind-source gaseous hydrogen delivered by pipelines from production point to distant markets (about 200-1000 mi.) at an untaxed wholesale energy unit cost will be competitive with market prices (in 2005) of gasoline and hydrogen fuel made from natural gas by steam methane reforms (SMRs). 

SCO SCPC SD SEC SMR SNG SOFC SPE SRES SULEV SUV Synthetic crude oil Super-critical pulverised coal System dynamics US Securities and Exchange Commission Steam methane reformer Synthetic natural gas Solid-oxide fuel cell Society of Petroleum Engineers IPCC Special Report on Emissions Scenarios Super-ultra-low-emission vehicle Sport utility vehicle... 

Increasing the pressure in a MCFC system can also increase the likelihood of soot formation and decrease the extent of methane reforming. Both are undesirable. Furthermore, the effect of contaminants on the cell and their removal from a pressurized MCFC system have not been quantified. The increased pressure also will challenge the fuel cell seals (37). 

Methane reforming units receive methane-rich gas from a cryogenic product recovery facility and subject the gas to partial oxidation. Some of the carbon dioxide content is removed and the gas recycled to the reactors. Once liquids are recovered, the stream goes to essentially conventional refining units. The plant s production is primarily transport fuels. Most of the gasoline production is currently sold to other refineries for blending with their stocks, but a portion of the product is marketed directly to consumers. 

Beil, A. and Seume, J. (2006) Unsteady performance of a PEMFC system including autothermal methane reforming, in Proceedings of the 4th International ASME Conference on Fuel Cell Science, Engineering and Technology, June 19-21, Irvine, CA. 

The application of this method is shown in Figure 5, where hydrogen is produced by the nuclear-heated steam methane reforming (using a sodium-cooled reactor and natural gas), and then this hydrogen is converted into electricity in the alkaline-type fuel cell. 

The oil industry has to enrich crude oil with hydrogen to produce lighter petroleum products. Today, the vast majority of hydrogen in refineries is produced by steam methane reforming, this production accounts for approximately 1% ( 0.3 Gt) of the C02 world emissions. For comparison, it is approximately equal to 15% of avoided C02 emissions thanks to the world nuclear reactors fleet. Besides, the tradition Fischer-Tropsch process to produce synfuels has a poor conversion yield and is a large C02 emitter one-third of the resource is used to produce the hydrogen required for the process, when another third is used to produce the energy required for the process. Two-thirds of the carbon resource is therefore converted directly into C02, and not into fuel. 

Natural gas can also be used to make hydrogen fuel. About 95 percent of the hydrogen produced today in the United States is made through a process called steam-methane reforming. During this process, the methane that is in natural gas reacts... 

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