Hydrogen enrichment

At the exit of the WGS reactor, the reacted CaC03 particles are captured by a high-temperature cyclone and the spent solids are then sent to a rotary calciner to thermally decompose the CaC03 back to CaO at temperatures between 660°C and 900°C with pure C02 formed in the outlet gas stream. The pure C02 gas can be economically compressed, cooled, liquefied, and transported for its safe sequestration. Hydrogen can be used for various energy conversion systems or hydrogen-enriched fuel production without any further low-temperature cleanup requirement. 

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. 

Hydrogen-enriched natural gas buses are expected to meet the California Air Resources Board s transit emissions requirements. They also pave the way for a hydrogen infrastructure that can support fuel cells for transportation. The use of hydrogen powered buses and infrastructure facilities conforms with the goals of the California Fuel Cell Partnership, the U.S. Department of Energy, the U.S. Department of Transportation, and the U.S. Environmental Protection Agency. 

Conversion of hunters and other design aspects of heating systems and appliances to pure hydrogen, or to a hydrogen-enriched natural or substitute natural gas supply, while costly and inconvenient, is certainly not in the economically insurmountable category. Similar alterations over the years were made in Ihe United States when communities switched from manufactured gas (about 5tlr- hydrogettt to natural gas. Such switchovers arc ever) more recent in European communities. 

Thermal power generated by the reactor is converted to chemical power in a thermal conversion unit where, in the MHR-T option with methane reforming, thermochemical reaction is initiated converting initial steam-gas mixture to hydrogen-enriched converted gas (mixture of water steam, CO, H2, C02, and CH4). 

Gas permeation Vapour Non-porous membrane with pressure gradient Hydrogen enrichment... 

The quality of the solvent also affects the conversion levels. With the hydrogen-enriched solvent (-019) conversions approach maximum levels at all reaction severities tried in this work and no retrograde reaction was observed to reform pyridine insolubles, A maximum conversion followed by a decline in conversion was seen with the hydrogen-depleted solvent (-035) with both coals. The maximum conversions are 5 to 10 percent lower with the hydrogen-poor solvent than the best observed conversions obtained with the hydrogen-rich solvent for each coal ... 

A comparison of the effect of the two solvents on the composition of SRCs from Wyodak subbituminous coal is shown in Figure 8. Compared to the hydrogen-enriched solvent, use of the hydrogen-depleted solvent results in a SRC with higher sulfur and oxygen contents and lower carbon and hydrogen contents. 

MAF conversions to pyridine solubles from short contact time coal liquefaction are dependent on the coal type, solvent source, and reaction severity. As reaction severity increases conversions approach a maximum value with a hydrogen-enriched solvent but go through a maximum and decline with a hydrogen-depleted... 

Comparison of analyses of heptane insolubles from the liquefaction of Monterey bituminous and Wyodak subbituminous coals in the hydrogen-enriched solvent shows that carbon, hydrogen and oxygen concentrations converge with increasing reaction severity to form a product with similar elemental analyses. The same convergence is seen when the hydrogen-depleted solvent is used. 

The solvents which have been used to date represent two extremes (Table 1). One is a hydrogen enriched (9.67% H) SRC-1 recycle solvent (92-26-019) while the other is a hydrogen depleted (8.15% H) SRC-1 preheater effluent solvent (92-03-035). Reactions were performed in a 300 cc stainless steel batch autoclave which has been previously described in detail (1). The experimental procedure has also been described (2). Experiments in this paper were performed at 1400 psig of hydrogen at a solvent to coal ratio of three to one. 

There are indications that the formation of these initial hydrogen enriched products and the rate at which the hydrogen content subsequently decreases is dependent upon the solvent donor capacity. 

Methanol is produced from carbon monoxide, carbon dioxide, and hydrogen. The proper feed composition is achieved by combining the hydrogen-enriched syngas from the shift reactor and the hydrogen-carbon monoxide stream from the gas separation unit. The feed stream... 

For the hydrogen enrichment of uents from hydrotreating units, Monsanto s Prism TM process, using gas containing 60 to 75 per cent H2 (=15,006 m /h) available at 3.5 to 5.5.10 Paabsolute,fumishesaproductwithapurityof92to98percentvolume,witha yield of 80 to 90 per cent at 2.10 Pa absolute. 

Hydrogen enrichment of the gas obtained by partial oxidation or steam reforming... 

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