Hydrogen rich gases

In the two-stage operation, the feed is hydrodesulfurized in the first reactor with partial hydrocracking. Reactor effluent goes to a high-pressure separator to separate the hydrogen-rich gas, which is recycled and mixed with the fresh feed. The liquid portion from the separator is fractionated, and the bottoms of the fractionator are sent to the second stage reactor. 

As a constituent of synthesis gas, hydrogen is a precursor for ammonia, methanol, Oxo alcohols, and hydrocarbons from Fischer Tropsch processes. The direct use of hydrogen as a clean fuel for automobiles and buses is currently being evaluated compared to fuel cell vehicles that use hydrocarbon fuels which are converted through on-board reformers to a hydrogen-rich gas. Direct use of H2 provides greater efficiency and environmental benefits. ... 

Several types of nonthermal plasma systems have been reported in the literature for reforming of hydrocarbons to hydrogen-rich gas ... 

The authors concluded that for the production of hydrogen-rich gas, diesel fuel could be reformed by exhaust gas at temperatures typical of exhaust gas temperatures (from 200 to 700°C). 

There are different process configuration concepts where FBs form the heart of the technology for the hydrogen-rich gas production. The following recently developed gasification reactor technology can be especially mentioned in this respect 44... 

Features of Different Gasifiers for Large-Scale Hydrogen-Rich Gas Production from Biomass... 

Hofbauer, H. Rauch, R. Foscolo, P. Matera, D., Hydrogen rich gas from biomass steam gasification. 1st World Conference on Biomass for Energy and Industry, Sevilla, 2001, pp. 1997-2001. 

Because the synthesis gas produced from coal is generally relatively poor in hydrogen, a typical CO H2 ratio being ca. 1 1, and because, as can be seen from Eqs. (14) and (15), a hydrogen-rich gas is required for the production of hydrocarbons and chemicals, a hydrogen enrichment step is usually necessary for the Fischer-Tropsch process. 

Koppers-Totzek A coal gasification process using an entrained bed. The coal is finely ground and injected in a jet of steam and oxygen into a circular vessel maintained at 1,500°C. Reaction is complete within one second. The ash is removed as a molten slag. The process was invented by F. Totzek at Heinrich Koppers, Essen, and further developed by Koppers Company in Louisiana, MO, under contract with the U.S. Bureau of Mines. The first commercial operation was at Oulu, Finland, in 1952 by 1979, 53 units had been built. Most of the plants are operated to produce a hydrogen-rich gas for use in ammonia synthesis. Developed by Lurgi. See also PRENFLO. 

Garcia, L., Sanchez, J.L., Salvador, M.L., Bilbao, R., and Arauzo J. (1996). Hydrogen-rich Gas from Steam Gasification of Biomass Using Coprecipitated Nickel-alumina Catalysts, Bioenergy 96. The Seventh National Bioenergy Conference, pp. 859-865. 

Gary Jacobs and Burt Davis (University of Kentucky) review catalysts used for low-temperature water gas shift, one of the key steps in fuel processors designed to convert liquid fuels into hydrogen-rich gas streams for fuel cells. These catalysts must closely approach the favorable equilibrium associated with low temperatures, but be active enough to minimize reactor volume. The authors discuss both heterogeneous and homogeneous catalysts for this reaction, with the latter including bases and metal carbonyls. 

Ideal stoichiometric reaction equations for, respectively, synthesis gas, hydrogen-rich gas and methane-rich gas production by gasification are given by reactions (1) to (3) ... 

Raw Fuel Conversion - Converting a hydrocarbon fuel to a hydrogen-rich gas reformate. 

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