配煤燃烧过程中煤灰熔融性研究

采用灰熔点较低的神华煤和较高的准格尔煤以及这两种煤组成的混煤在沉降炉内进行实验，模拟实际电站锅炉内结渣的形成过程。采用SEM、XRD技术对煤粉和灰渣的微观形貌和晶相成分进行分析。结果表明，准格尔煤粉中包含的大量高岭石和勃姆石为莫来石的大量生成提供了条件，神华煤中不含勃姆石，高岭石的含量也不多，莫来石的生成量很少。莫来石在高温下遇到石灰石的分解产物CaO，要与之反应生成钙长石，这是神华煤灰渣中没有检测到莫来石衍射峰的主要原因。莫来石是一种高熔点矿物（1850℃），能显著改善煤灰的熔融温度，神华煤灰渣中不含莫来石，灰渣中缺少大量能在其熔融过程中发挥“骨架”作用的成分，这是导致神华煤灰熔融温度较低的一个重要原因。

Study on the coal ash fusibility during blending coal combusition

The experiments to simulate the slagging processes in the power plant boilers were carried out in a drop tube furnace with Shenhua coal,Zhungar coal and the blends of these two coals which are of different ash fusion temperatures.SEM and XRD techniques were used to analyze the surface morphology as well as the crystalline compositions of the residue.The result shows that a great mass of kaolinite and boehmite in Zhungar coal are turned ioto mullite.There is no boehmite and less kaolinite found in Shenhua co...