Browse Topic: Coal gasification

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Chemical Kinetics and Computational Fluid-Dynamics Analysis of H 2 /CO/CO 2 /CH 4 Syngas Combustion and NOx Formation in a Micro-Pilot-Ignited Supercharged Dual Fuel Engine2017-24-00279/4/2017
A chemical kinetics and computational fluid-dynamics (CFD) analysis was performed to evaluate the combustion of syngas derived from biomass and coke-oven solid feedstock in a micro-pilot ignited supercharged dual-fuel engine under lean conditions. For this analysis, a reduced syngas chemical kinetics mechanism was constructed and validated by comparing the ignition delay and laminar flame speed data with those obtained from experiments and other detail chemical kinetics mechanisms available in the literature. The reaction sensitivity analysis was conducted for ignition delay at elevated pressures in order to identify important chemical reactions that govern the combustion process. We have confirmed the statements of other authors that HO2+OH=H2O+O2, H2O2+M=OH+OH+M and H2O2+H=H2+HO2 reactions showed very high sensitivity during high-pressure ignition delay times and had considerable uncertainty. The chemical kinetics of NOx formation was analyzed for H2/CO/CO2/CH4 syngas mixtures by using counter flow burner and premixed laminar flame speed reactor. The new mechanism showed a very good agreement with experimental measurements and accurately reproduced the effect of pressure, temperature and equivalence ratio on NOx formation. In order to identify the species important for NOx formation, a sensitivity analysis was conducted for pressures 4 bar, 10 bar and 16 bar and preheat temperature 300 K. The results show that the NOx formation is driven mostly by hydrogen based species while other species, such as N2, CO2 and CH4, have also important effects on combustion. Finally, the new mechanism was used in a multidimensional CFD simulation to predict the combustion of syngas in a micro-pilot-ignited supercharged dual-fuel engine and results were compared with experiments. The mechanism showed the closest prediction of the in-cylinder pressure and the rate of heat release (ROHR).
Stylianidis, NearchosAzimov, UlugbekKawahara, NobuyukiTomita, Eiji
During the Ten-Year War 1935-1945, the Japanese Navy played a leading role in the R&D and production of domestic aviation fuels and high-grade lubricants, by means of technological imports from abroad (mainly from the U.S.A.) at the beginning and of self-development in the latter part of the period. One of the features is a hydrogenation process, which was started with catalyst development and successfully achieved production in large-scale plants. The efforts also achieved certain self-sufficiency in high-grade lubricants that had been dependent on imports.
Katoh, Fusanosuke
A Review and Comparison of Reciprocating Engine Operation Using Solid Fuels8313629/12/1983
Future fuels for internal-combustion engines will be derived increasingly from solids such as coal. An alternative to processing coal into liquid fuels is the direct use of solid coal by reciprocating, internal -combustion engines. Specific applications which would be especially suitable for solid fueled engines consist of stationary power plants, marine propulsion systems, and railroad locomotives. Agricultural, construction and mining equipment are examples of other possible applications. The objectives of this study were to review past research on the development of solid coal fueled engines and, from this review, to identify major technical problems and current research needs. The objectives also included comparing the energy usage of several fuels. This comparison indicated a possible 25% energy advantage by directly using solid coal fuels as opposed to using synfuels. The literature review indicated that operation of solid reciprocating engine has been attempted for nearly a hundred years. Problems which have been encountered continuously have involved the fuel delivery system, solid-particle combustion, and engine component wear. Recent investigations (1979-1982) using coal/oil, carbon-black/oil, and coal/water slurries in a variety of reciprocating engines have yielded encouraging results. The use of coal/water slurries is an attractive approach to using solid coal in engines, since fuel handling problems are simpler than using dry-powder fuels, and the slurry is petroleum independent.
Caton, J. A.Rosegay, K. H.
Another Look at Alternative Fuel Options7707592/1/1977
Alternatives to petroleum-derived transportation fuels can be produced from oil shale, coal, and from a variety of carbonaceous materials including both cultivated biomass and waste materials. In the long-term, hydrogen, often mentioned as an alternative fuel, may be used as an energy carrier or transfer agent; it should not, however, be considered as an energy resource. Among the alternatives, coal-derived or shale-derived fuels could become significant in the national supply within the century. The other alternatives are long-term (post-2000), or, at least without extensive resource development, they are resource-limited. Any identifiable shale-derived fuel probably will appear as conventional finished fuel--either gasoline or distillate. More likely, however, the shale-derived component of fuels will not be identifiable because any shale oil available for the manufacture of transportation fuels within the foreseeable future will be blended with natural crude and used as refinery feedstock. Coal-derived fuels may be methanol, gasoline from methanol, or conventional gasolines or distillate-type fuels either synthesized from coal or refined from coal syncrude, i.e., a “liquefied” coal. Methanol or a methanol derivative would be produced using coal gasification as the primary conversion process. The technology for coal gasification is well established whereas that for coal liquefaction is not fully developed. For this reason methanol or methanol-derived gasoline are the alternative fuels most likely of production if non-petroleum fuels were to be required in the immediate future. The next most likely would be conventional fuels from coal synthesis by the SASOL process. The evidence available to date indicates that should gasoline or distillate be made from either coal or shale oil those fuels will not differ markedly from traditional fuels.
Hurn, R. W.
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