含气化剂煤气深度气化研究

FIXDE-BED STUDY ON COAL CHAR GASIFICATION WITH GASIFIER OUTLET GASES

利用自制小型加压固定床气化炉研究气化剂为混合气的煤焦气化。混合气为含CO2 、CO、H2 和水蒸气的气体 ,它是模拟水煤浆气化炉出炉煤气成分在实验室制得的。实验考察气化温度、气化剂流速、混合气气体成分对煤焦气化的影响。实验发现 ,煤焦气化温度越高 ,气化剂流速越大 ,煤焦气化反应速度越快 ;H2 、CO对煤焦气化有阻滞作用。

Gasification behavior of coal char with synthesis gas mixtures was investigated in detail by using pressurized fixed-bed gasifier. Schematic diagram of coal char gasification was introduced. Char was prepared from Shenfu coal by devolatilization in nitrogen at 930?℃. The synthesis gas mixtures composition was similar to gasifier outlet gas which consisted of H 2, CO, CO 2 and steam. Results indicated that gasifier outlet gases could react with coal char rather rapid when the gasification temperature was above 1?000?℃. The total carbon conversion and reaction rate increase with raising temperature or gas folw velocity. The influence of reactive gases on coal char gasification was also studied. The gaseous media used was steam, steam-hydrogen, carbon dioxide and synthesis gas mixtures. The lower gasification rate in the steam-hydrogen and synthesis gas mixtures could be explained on the basis of retardation of the steam-carbon reaction by hydrogen in the case of gasification with the steam-hydrogen mixtures and by both hydrogen and carbon monoxide in the case of gasification with synthesis gas mixtures.