【摘要】 为探索准东煤的煤气化反应特性,采用固定床反应器对准东煤在水蒸气/氢气气氛下进行气化实验研究,得到准东煤在850~950℃下的混合气氛气化反应特性与气体释放规律。结果表明,水蒸气的引入能明显提高气化反应前期的反应速率和碳转化率,同时会抑制CH4的生成。煤的气体释放过程可以分为2个阶段:第1阶段的反应速率较快,而第2阶段的反应速率受气氛影响明显。采用拉曼光谱分析对残焦结构进行了分析,结果表明,水蒸气的引入会更彻底地将反应官能团消耗掉,同时也会加快煤焦的缩聚反应和惰性化,使气化反应性在第2阶段降低的更快。这主要是由于混合气氛导致气化反应平衡和孔内反应界面发生变化。通过调整反应气氛中不同组分的比例,可以在一定范围内调整合成气的成分。更多还原

【Abstract】 The properties of Zhundong coal’s gasification in H2/H₂O atmosphere were studied with a fixed-bed gasification reactor. The gas-releasing rates and compositions of gas production were investigated from 850 ℃ to 950 ℃. The results indicate that hydrogen improves reaction rate and gas production,but the release of methane decreases with the increasing proportion of steam. The gasification of raw coal can be divided into two stages,the gasification rate is high in the first stage,but it depends on the atmosphere in the second stage. The result of Raman spectra analysis on the residual chars indicate that introducing steam into hydrogasification enhances the graphitizing rate of chars and consumed more oxygen functional groups,leading to a faster decrease of char’s activity,and less gas production in the second stage. The influence of mix-atmosphere on the reaction equilibrium and the reaction interface in pores can explain those phenomena. The compositions of gas production can be controlled by changing the reaction atmosphere.更多还原