202002

准东煤灰的矿物转化及熔融机理
发布人:网站管理员 发布时间:2020/3/16 点击次数:134次
  

准东煤灰的矿物转化及熔融机理
龚宇森,许天瑶
(华中科技大学能源动力工程学院,湖北 武汉 430074)
摘要: 准东煤在燃烧过程中严重的沾污结渣倾向对电站锅炉的安全运行造成严重危害。通过TGA-DSC 综合热分析确
定煤灰矿物相变的特征温度,并对不同特征温度下的灰样采用XRD 和FSEM-EDS 分析手段,得到了煤灰中主要矿物的
相变和转化过程。研究表明,部分钠矿物以霞石的方式存在于煤灰中,因此留于煤灰中的Na 在高温段以蓝方石的形式
存在;随着温度的升高,煤灰中矿物晶相向多元系发展;相同元系数的矿物元素价态越高,其高温稳定性越好。煤灰的
矿物转化伴随着物理相变,煤灰熔融宏观变化是灰中各矿物微观转化过程的大量积累结果。
关键词: 准东煤;灰熔融性;矿物相变;XRD;FSEM-EDS
中图分类号: TK16     文献标识码: A     文章编号: 2095-0802-(2020)02-0037-03
Mineral Transformation and Melting Mechanism of Zhundong Coal Ash
GONG Yusen, XU Tianyao
(School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China)
Abstract: The serious fouling and slagging tendency of Zhundong coal in the combustion process will cause serious harm to the
safe operation of power plant boilers. The characteristic temperature of coal ash mineral transformation was determined by TGADSC
comprehensive thermal analysis, and the phase transformation and transformation process of the main minerals in coal ash
were obtained by XRD and FSEM-EDS analysis. The results show that some sodium minerals exist in the form of nepheline in the
coal ash, so the sodium retained in the coal ash exists in the form of bluestone in the high temperature section; with the increase
of temperature, the mineral crystalline phase in coal ash develops to multi-component system; the higher the valence state of
mineral elements with the same element coefficient, the better the high temperature stability. The mineral transformation of coal
ash is accompanied by physical phase transformation, and the macro change of coal ash melting is the result of a large number of
micro transformation processes of various minerals in the ash.

Key words: Zhundong coal; ash fusibility; mineral phase transformation; XRD; FSEM-EDS