High-temperature steam reforming

Options HDS or Steam reforming High temperature Selective oxidation... 

Conventional processes for the production of syngas involve partial oxidation or steam reforming. In the process with oxygen, an expensive air-separation plant is required, whereas in the case of steam reforming high-temperature heat additions are necessary. 

Steam, at high temperatures (975-1375 K) is mixed with methane gas in a reactor with a Ni-based catalyst at pressures of 3-25 bar to yield carbon monoxide (CO) and hydrogen (H ). Steam reforming is the process by which methane and other hydrocarbons in natural gas are converted into hydrogen and carbon monoxide by reaction with steam over a nickel catalyst on a ceramic support. The hydrogen and carbon monoxide are used as initial material for other industrial processes. 

Thermal power for hydrogen production by steam methane reforming/ high-temperature water electrolysis, MW 4 x 160/4x211... 

Hydrogen production efficiency, t/h (m3/h), minimum - steam methane reforming - high-temperature water electrolysis 4 x 12.5 (138.75-103) 4x6.76 (75-103)... 

Example 4.10 One method for the manufacture of synthesis gas (primarily a mixture of CO and H2) is the catalytic reforming of CH4 with steam at high temperature and atmospheric pressure ... 

In steam reforming, natural gas (consisting chiefly of methane) is mixed with steam at high temperatures and pressures over a heterogeneous catalyst to generate carbon monoxide and hydrogen ... 

Nuclear-heated steam-methane reforming (High temperature reforming, S. Shiozawa - JAERI, Ref. 9. Medium temperature reforming, M. Tashimo - ARTEC, Ref 10. Low temperature reforming of DME, Fukushima - Toshiba, Ref. 11)... 

The commercial production of hydrogen is carried out by treating natural gas with steam at high temperatures and in the presence of a catalyst ( steam reforming of methane ) ... 

The eight kinds of catalysts may be roughly classified as protective catalysts and economic catalysts . Co-Mo hydrogenation catalyst and zinc oxide desulfurizer are the protective catalysts for the primary steam reforming catalysts. The high-temperature shift catalyst protects the low-temperature shift catalyst, and the methanation catalyst are the protective catalyst for ammonia synthesis catalyst. The catalysts for primary- and secondary-steam reforming, low-temperature shift and ammonia synthesis are responsible for the conversions of raw materials and the yield of products, and have direct effect on economic benefits of the whole plant, and are thus called as economic catalysts. The amount of catalysts used depends on the process and raw material. Table 1.2 represents the amount of the eight kinds of catalysts used in the different processes. The total volume of the catalysts is about 330 m in every plant, while there are only two kinds of catalysts with the volume of about 100-140 m when heavy oil or coal is used as raw material. Both shift... 

Steam reforming process used in ammonia plants. Natural gas feed. Sulfur absorption on activated carbon secondary reforming high temperature shift catalysts used. Reformer-pressure increasing from atmospheric to 9bar. Plant capacity increasing from 150 tpy to 300 tpy. 

Phosphoric Acid Fuel Cell. Concentrated phosphoric acid is used for the electrolyte ia PAFC, which operates at 150 to 220°C. At lower temperatures, phosphoric acid is a poor ionic conductor (see Phosphoric acid and the phosphates), and CO poisoning of the Pt electrocatalyst ia the anode becomes more severe when steam-reformed hydrocarbons (qv) are used as the hydrogen-rich fuel. The relative stabiUty of concentrated phosphoric acid is high compared to other common inorganic acids consequentiy, the PAFC is capable of operating at elevated temperatures. In addition, the use of concentrated (- 100%) acid minimizes the water-vapor pressure so water management ia the cell is not difficult. The porous matrix used to retain the acid is usually sihcon carbide SiC, and the electrocatalyst ia both the anode and cathode is mainly Pt. 

Steam reforming of CH is commonly carried out at 750 to 900°C, thus at the lower operating temperature of MCFCs a high activity catalyst is required. The internal reforming of methane in IRMCFCs, where the steam-reforming reaction... 

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