Kinetics of Carbon Gasification by Steam. Mechanism of Interaction of Low Temperature Char and Steam-Hydrogen Mixtures at 1600 °F.

Laboratory support for in situ gasification reaction kinetics. Quarterly report, October--December 1976

“…Hence, catalysis of this reaction that was observed in previous runs at temperatures as low as 600*C can be attributed only to the char bed itself--most likely to the mineral matter in the char. Goring et al 2 have postulated the former model but could not describe in detail a mechanism for this direct interaction of steam and carbon to produce methane.…”

Kinetics of Bituminous Coal Char Gasification with Gases Containing Steam and Hydrogen

“…Cv (volatile carbon), grams/gram feed coal = Ct° (total carbon), grams/gram feed coal -Cb° (base carbon), grams/gram feed coal (1) where Ct° represents the total carbon in the feed coal char obtained from an ultimate analysis, and Cb° represents the carbon in the fixed carbon fraction of the feed coal as determined in a proximate analysis. Note that Cb° does not equal the fixed carbon fraction because the fixed carbon fraction includes, in addition to carbon, other organic coal components not evolved during standard devolatilization.…”

“…These limitations have no practical significance in using the simplified model developed to describe coal char gasification kinetics at higher temperatures or for base carbon conversion levels sufficiently greater than 10%. The gasification data of Zielke and Gorin (2,3) and Goring et al (1) for fluid-bed gasification of Disco char as well as the bulk of data obtained in IGT studies with the high pressure thermobalance and pilot-scale fluid beds were used to evaluate parameters in a quantitative model developed to describe coal char gasification kinetics over a wide range of conditions in the low-rate gasification stage. Three basic reactions were assumed to occur in gases containing steam and hydrogen: Reaction I: H20 + C *± CO + H2…”

“…The experimental information used to develop the models came from two main sources. Initial development of the model applied to the gasification of devolatilized coal char in hydrogen and steam-hydrogen mixtures was based both on data from an IGT study with a high pressure thermobalance apparatus and on differential rate data from the Consolidation Coal Co. on the gasification of Disco char in a small-scale fluid bed (1,2,3). The model was extended to the gasification of char containing volatile matter and to gasification with gases containing carbon monoxide, carbon dioxide, and methane as well as steam and hydrogen using data primarily from the thermo balance study.…”

“…Effect of temperature on low-rate gasification in steam-hydrogen mixtures (thermobalance data) Effects of pressure and gas composition on low-rate gasification in steam-hydrogen mixtures(1,3) …”