Carbonaceous material and methods for making hydrogen and light hydrocarbons from such materials

Claim 1

A continuous steam gasification process for producing a high heating value gas stream containing methane and hydrogen from a low heating value fuel gas containing carbon monoxide and hydrogen comprising the steps of: (a) reacting in a steam gasification zone a fibrous carbon-enriched carbonaceous material with steam at a temperature of from about 500° C. to about 750° C. and a pressure of from about 1 to about 100 atmospheres to gasify at least about 40% of the carbon in the fibrous carbon-enriched carbonaceous material to produce (i) a high heating value gas stream containing methane and hydrogen and (ii) a fibrous carbon-lean carbonaceous material, the fibrous carbon-enriched carbonaceous material comprising from about 55% to about 98% by weight carbon, from about 1% to about 44% by weight ferrous group metal component, and from about 0.1% to about 1% by weight hydrogen, the ferrous group metal component containing at least 70% by weight nickel, cobalt, and combinations thereof and not more than 30% by weight iron, the fibrous carbon-enriched carbonaceous material including a major phase and a minor phase, the major phase comprising from about 95% to about 99.9% by weight carbon, from about 0.1% to about 1% by weight hydrogen, and the balance, if any, being the ferrous group metal component, the minor component being nodules which are dispersed throughout the major phase and are intimately associated with and at least partly bonded to the carbon in the major phase, the minor phase comprising carbon and at least 50% by weight ferrous group metal component; (b) withdrawing from the steam gasification zone (i) the high heating value gas stream and (ii) a solid phase consisting essentially of the fibrous carbon-lean carbonaceous material; (c) reacting in a carbon deposition zone the withdrawn fibrous carbon-lean carbonaceous material with the low heating value fuel gas at a temperature of from about 300° to about 700° C. to deposit carbon on the fibrous carbon-lean carbonaceous material to form (i) the fibrous carbon-enriched carbonaceous material and (ii) depleted low heating value fuel gas; (d) withdrawing from the carbon deposition zone a solid phase consisting essentially of the fibrous carbon-enriched carbonaceous material; (e) recycling carbon-enriched carbonaceous material withdrawn from the carbon deposition zone to the steam gasification zone; and (f) lowering the temperature of the withdrawn high heating value gas stream and contacting it with the fibrous carbon-enriched carbonaceous material at a temperature of 300° to 500° C. for increasing the heating value of the high heating value gas stream.