摘要
为深入理解燃煤颗粒物的形成机理,利用计算机控制扫描电镜技术对煤及其颗粒物中的无机矿物进行了详细表征,研究了煤燃烧过程中主要矿物向颗粒物的转化规律。结果表明煤中粘土矿物由于含有K、Na、Ca、Mg和Fe等杂质元素,容易在较低温度下发生熔融和聚合,从而使颗粒粒径变大.黄铁矿在燃烧中易发生分解、破碎而使颗粒粒径减小,Fe氧化物与硅酸盐发生反应形成富Fe硅酸盐。方解石和铁白云石在高温条件下分解生成对应的氧化物,也可与硅酸盐发生反应形成富Ca或富Fe硅酸盐.石膏在燃烧过程中会经历脱水和分解反应,生成的CaO可与SO3和熔融硅酸盐发生竞争反应.
For a further understanding of particulate matter formation during coal combustion, the mineralogy of a bituminous coal and its combustion-generated particles was characterized in detail by computer controlled scanning electron microscopy （CCSEM）. The transformations of major coal minerals into particulate matter during combustion were carefully investigated. The results show that clay minerals may melt and coalesce at a lower temperature due to the presence of some impurity elements such as K, Na, Ca, Mg or Fe, which leads to an increase in particle size. Pyrite tends to undergo decomposition and fragmentation, resulting in a decrease in particle size. Iron oxides can react with silicates and form Fe-rich silicates. Calcite and ankerite decompose into their corresponding oxides at high temperatures, which can also react with silicates and form Ca- or Fe-rich silicates. Gypsum experiences dehydration and decomposition during combustion. There is a competition reaction between SO3 and silicates with the produced CaO.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2008年第3期507-510,共4页
Journal of Engineering Thermophysics
基金
国家重点基础研究发展计划(No.2002CB211602)
国家自然科学基金(No.50721005
No.50706013)
关键词
煤燃烧
矿物
颗粒物
CCSEM
coal combustion
mineral
particulate matter
CCSEM
