摘要
在固定床反应器上研究了焦炭在CO2 气氛下的气化反应，分析了气化温度和颗粒大小，以及颗粒表面灰的聚集对气化反应的影响。采用两段阶梯式气化方法和扫描电镜（SEM），研究气化反应过程中灰的附着对气化效果的影响。结果表明，温度对气化反应有积极影响，在950 C～1265 C范围内温度越高气化效果越好，在1265 C时，焦炭转化率高达95％。颗粒粒径在小于20mm时，其变化对气化效果的影响不明显，而大于20mm时气化效果有明显的伴随下降趋势．这对于固定床气化焦炭时对焦炭的选取具有指导意义。
Coal char samples were gasified with carbon dioxide in a laboratory-scale fixed-bed gasifier. Some effects on chemical reaction rate were detected, such as temperature, particle size and the congregate of ash during gasification. The temperature and pressure conditions are the same as a real fixed-bed gasifier. SEM and a new two-stage method were used to detect the ash congregate effects on the reaction. Results show that temperature has a positive effect on gasification rate within the temperature range from 950 C to 1 265 C. The carbon conversion rate reached 95% when the temperature is 1 265 C. Ash formed during gasification process, it will prevent the agent diffuse into the inner surface of the particle, thus reduce the reaction rate. Particle size didn＇t have significant effect on reaction rate when it is smaller than 20 mm. But if the particle is bigger than 20 mm,the bigger the particle is the lower the reaction rate will be. This can be a guidance when choosing the right particle size for real fixed-bed gasifier.
出处
《煤炭转化》
CAS
CSCD
北大核心
2008年第2期48-51,共4页
Coal Conversion
关键词
焦炭
CO2
气化
温度
粒径
分段阶梯式气化
coal char, carbon dioxide gasification, temperature, particle size, two-stagegasification
