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Pressurized turbulent circulating fluidized-bed (CFB) gasification of bituminous coal is successfully realized in a lab-scale fluidized-bed gasifier, and the effects of the stoichiometric ratio, steam/coal ratio, and preheated temperature of the gasifying agent on coal gasification characteristics are studied in this work. Experimental results prove the feasibility of a high-temperature air/steam-blown gasification process. The lower heater value is increased by 21%, when the preheated temperature of the gasifying agent is increased from 400 to 700 °C. When the stoichiometric ratio and steam/coal ratio increased, the component of syngas has a regular change according to the gasification temperature. With the increase of the stoichiometric ratio, the gasification temperature is increased, the H2 concentration increased first and then decreased, the CH4 concentration decreased, and the CO and CO2 concentrations increased first and vary little in the second stage because of the steady gasification temperature. With the increase of the steam/coal ratio, the gasification temperature shows a decrease tendency, the CH4 concentration in gas remains basically unchanged, the CO concentration decreases appreciably, and the H2 concentration first increases and then decreases, while the CO2 concentration shows the opposite trend of H2. This indicates that the gasification temperature is the most important factor influencing coal gasification. Parameters of the equivalence ratio and steam/coal ratio exist at an optimum operating range, and at this range, the coal gasification shows advantages in lower heating value, cold gas efficiency, and carbon conversion for the bituminous coal CFB gasification process. In comparison to the two other representative types of gasifications using Chinese bituminous coal, pressurized CFB gasification decreases the carbon content of fly ash much better.

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