Hydrogen production coal gasification

O Keefe, L.F., Hydrogen Production, Coal Gasification and FutureGen Initiative, paper presented at Accelerating Deployment of Hydrogen Fuel Cell Vehicles, The Keystone Center, Washington, DC, June 5, 2003. 

Table 7.20. Input and output data for the production of hydrogen via coal gasification without CO 2 capture and storage ...

US activities under the Hydrogen from Eossil Euels Program, provide a good indication of key R D work to improve the production of hydrogen from coal gasification ... 

Table 6.6 summarizes the sensitivity of hydrogen from coal gasification to coal prices and overall process efficiency. The EIA forecasts coal prices of 1.25 /MBtu by 2020. A doubling of these prices would increase hydrogen production costs by 0.21 /kg. The results are not affected particularly by small changes in efficiency (-1-/—10%). 

This example demonstrates the "what if " capabilities of HjSim. Using the default assumptions, the cheapest production option for hydrogen is coal gasification (0.81 /kg), followed by natural gas reformation (1.43 /kg). Hydrogen produced from electrolysis is considerably more expensive (2.80 /kg). This example demonstrates how HjSim can be used to find the electricity price at which the electrolysis option is competitive. 

Chemistry. Coal gasification iavolves the thermal decomposition of coal and the reaction of the carbon ia the coal, and other pyrolysis products with oxygen, water, and hydrogen to produce fuel gases such as methane by internal hydrogen shifts... 

Gasification technologies for the production of high heat-value gas do not all depend entirely on catalytic methanation, that is, the direct addition of hydrogen to coal under pressure to form methane. 

Coal gasification technology dates to the early nineteenth century but has been largely replaced by natural gas and oil. A more hydrogen-rich synthesis gas is produced at a lower capital investment. Steam reforming of natural gas is appHed widely on an iadustrial scale (9,10) and ia particular for the production of hydrogen (qv). 

Hydrocarbons from Synthesis Gas and Methanol. Two very important catalytic processes in which hydrocarbons are formed from synthesis gas are the Sasol Eischer-Tropsch process, in which carbon monoxide and hydrogen obtained from coal gasification are converted to gasoline and other products over an iron catalyst, and the Mobil MTG process, which converts methanol to gasoline range hydrocarbons using ZSM-5-type 2eohte catalysts. 

Goal Processing to Synthetic Fuels and Other Products. The primary approaches to coal processing or coal conversion are thermal decomposition, including pyrolysis or carbonization (5,6), gasification (6), and Hquefaction by hydrogenation (6). The hydrogenation of coal is not currently practiced commercially. 

Hydrogen production by combining coal gasification with CCR process. 

Several new concepts under development for hydrogen production from coal were also described. The HyPr-RING method combines coal gasification, C02 separation, and water-gas shift reaction in a gasifier to produce hydrogen. 

Shiying L., Michiaki H., Yoshizo S. and Hiroyuki H., Hydrogen Production from Coal by Separating Carbon Dioxide during Gasification, Fuel, 81, 2079-2085, 2002. 

Iyer M.V., Gupta FT, Sakadjian B.B. and Fan, L.-S., High Temperature C02 Capture and Hydrogen Production Using Calcium Oxide Process Development and Economics for Combustion and Gasification Systems, The 2005 Clearwater Coal Conference, Apr. 17-21, Clearwater, FL, 2005. 

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