关键词:

湍动, 循环流化床, 预热温度, 煤气化, 压力

Abstract:

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.

Key words:

湍动, 循环流化床, 预热温度, 煤气化, 压力