摘要
选取了2种低阶煤在不同气氛下沉降炉中进行燃烧实验,产生的灰颗收集到粒旋风分离器和低压冲击器中,利用透射电子显微镜和扫描电镜分析亚微米颗粒和超微米颗粒的形态,利用扫描电镜能量色散谱仪联用,透射电子显微镜能量色散谱仪联用和计算机控制的扫描电镜分析灰颗粒的化学元素组成。研究结果表明:O2/CO2燃烧改变超细颗粒物的大小分布和灰中元素的浓度分布,但没有改变细颗粒的生成机制。对于含有更多有机结构矿物质的褐煤,O2/CO2燃烧提高了Fe、Na/K、Al和Si的气化程度,也因此增加了亚微颗粒的浓度,而且褐煤中的Fe元素的气化较为特殊,O2/CO2燃烧氧气浓度的增加提高了Fe气化后在其他粒子上的附着。
Two kinds of typical low-rank coal were burned in a drop tube furnace under different atmosphere. The produced particulate matters（PM） were collected by the cyclone and low pressure impactor（LPI）. Transmission electron microscopy（TEM） and scanning electron microscope （SEM） were used to identify the morphology of the super-micron and submicron PM. SEM with an energy dispersive X-ray（SEM-EDX）, TEM with an energy dispersive X-ray spectroscopy（TEM-EDS） and computer-controlled scanning electron microcopy（CCSEM） were applied to analyze the chemical composition in the ash. It has been confirmed that compared with air atmosphere, O2/CO2 atmosphere changes the generated fine ash particle size distribution and the concentration of the chemical composition, but the formation mechanisms are same for different atmosphere. For the case of the lignite with more amount of organic-associated minerals, O2/CO2 atmosphere increase the vaporization degree of Fe, Na/K sulfates, AI and Si, and thus increase the concentration of sub-micron particles. Also Fe is found to be a key element in the lignite. Oxy-fuel-combustion increases the attachment of vaporized Fe element to other particle.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2012年第29期52-58,I0008,共8页
Proceedings of the CSEE
基金
国家自然科学基金项目(50606035)~~
