气化剂预热温度对加压湍动循环流化床煤气化的影响

Effect of gasifying agent preheating temperature on pressurized turbulent CFB coal gasification

在实验室规模加压湍动循环流化床气化炉上,研究了气化剂预热温度对煤气化特性的影响。结果表明:气化介质温度从400℃提高到700℃后,煤气热值增加21%;煤气中可燃组分H2和CO浓度分别从10.55%和9.57%提高到13.62%和13.12%;不可燃组分N2和CO2浓度分别从61.03%和16.14%降低到57.03%和13.7%;甲烷含量变化较小;冷煤气效率由49.3%增加到56%。碳转化率和干煤气产率随气化剂预热温度的不同变化较小。实现了循环流化床提升段下部湍动流化、上部环核流动的特殊流场结构,与已有研究结果相比,煤气热值、煤气产率、冷煤气效率都略有提高,更加适合煤气化。

Pressurized turbulent circulating fluidized bed （CFB） gasification of coal in a lab scale fluidized bed gasifier was successfully realized, and the effect of gasifying agent preheating temperature on coal gasification characteristics was studied. Experimental results indicated that the gas thermal value was increased by 21% when the gasifying agent preheating temperature increased from 400℃ to 700℃. The concentration of combustible components hydrogen and carbon monoxide in the gas were increased from 10.55% and 9.57% to 13.62% and 13.12% respectively, while the concentration of incombustible components nitrogen and carbon dioxide in the gas were decreased from 61.03% and 16.14% to 57.03% and 13.7% respectively, and the concentration of methane changed slightly. Increasing the gasifying agent temperature would increase the gasification efficiency from 49.3% to 56%. The carbon conversion and dry gas yield changed little with the increase of the gasifying agent preheating temperature. A special flow field in the rising section of CFB has been realized with turbulent in the lower part and core-annulus in the upper part, which can not only enhance the fluidized state, but also promote the gas thermal value, gas yield and gasification efficiency, providing a more suitable way for coal gasification as compared with other CFB gasification experiments.