褐煤SHELL气化飞灰黏附影响因素的研究

Influencing factors on fly ash adhesion features in Shell lignite gasifier

通过激光粒度仪、X射线荧光光谱仪、扫描电子显微镜等现代化分析测试技术对褐煤样、飞灰样以及换热废锅中的积灰样进行了粒度分布、化学组成、晶体矿物组成、微观形貌、微区化学组成等特征的分析,研究影响飞灰黏附特性的因素。并通过引入富集系数,描述各个元素在煤灰、正常飞灰、废锅积灰中的迁移富集情况。结果表明,在废锅积灰中有含铁矿物的生成,同时Na、K、Fe、S、P元素在废锅积灰中发生富集,在飞灰与积灰颗粒边缘处有大量的Fe、Na元素的富集。

One coal and two representative fly ashes from the Shell gasification process were used in the study. One fly ash was the captured fly ash, and the other was taken from the heat exchanger. The particle size distribution, chemical composition, surface morphology of samples were studied by laser particle analyzer, X-ray fluorescence spectrometer and scanning electron microscopy respectively to explore the mechanisms of adhesion. The enrichment coefficient was used to describe the element migration from the coal to the fly ash. The results show that the formation of iron-bearing minerals and the enrichment of Na, K, Fe, S, P especially the enrichment of Na and Fe on the surface of fly ash particles are the main factors on the adhesion.