煤及煤焦微观结构特征与气化反应性

THE RELATIONSHIP BETWEEN GASIFICATION REACTIVITY AND NIICROSTRUCTURE CHARACTERISTICS OF COAL/COAL CHAR

研究了不同煤化度煤及煤焦的微观结构及其对气化反应性的影响。结果表明,褐煤焦具有丰富的分支孔系统和较大的比表面积,并含有较多对气化有催化作用的可交换阳离子。无烟煤焦分支孔贫乏,比表面积很小。煤焦的总孔容、比表面积和芳核大小之间有很好的对应关系。不同煤化度煤焦气化反应性差异很大,脱矿物质后煤焦反应性差异显著减小,但是脱矿物质前后煤焦的反应性随煤化程度的变化趋势相似。

The effect of microstructure characteristics of coal and coal char on gasification reactivity was investigated. Results that lignite char has abundant pore structure large specific surface area and many exchangeable positive ions which show catalytic influence on gasification reaction. Anthracite char has poor pore structure and small specific surface area. Good relationship exists among total pore volume, specific surface area and aromatic microcrystallite size in coal char. Large difference in gasification reactivity has been found for chars from different rank coals. This difference became small for demineralized coal chars of different rank. Nevertheless the variation tendency of gasification reactivity with coal rank is similar in either case.