配煤对煤灰熔融过程的矿物演变的影响

对高钙烟煤和低钙无烟煤以及这两种煤组成的混合煤进行灰熔融特性研究。利用灰熔点测试仪测定煤灰的灰熔融特征温度，通过FactSage热力学软件的Equilib模块和Phase Diagram模块计算煤灰熔化过程的物相变化。结果表明，煤的灰熔点与煤灰的成分密切相关，酸性物质能使混煤灰的熔融特性温度升高，碱性物质使混煤灰的熔融特性温度降低；通过FactSage的Equilib模块得到的熔化过程可以看出，烟煤和无烟煤煤灰的熔融特性差异是温度高于1 000 ℃时莫来石和钙铝黄长石的含量变化导致的。对于混煤灰，随着低钙无烟煤比例的增加，在1 000 ℃的矿相成分中莫来石含量增加，钙铝黄长石含量减少，导致混煤灰熔点提高。

Effect of coal blending on mineral evolution in coal ash melting process

The ash fusion properties of high calcium bituminous coal and low calcium anthracite and their blends were investigated. The ash fusion characteristic temperature was obtained by using ash melting point tester. And the phase transformation in melting process of samples′ash was calculated by Equilib module and Phase Diagram module of FactSage thermodynamics software. The results showed that the ash fusion point of the coal was closely related to the composition of coal, acidic substances in coal ash can increase the melting characteristics, while the alkaline materials can reduce the melting characteristics. The melting process obtained by FactSage showed that the difference in melting characteristics between bituminous coal and anthracite coal ash was caused by a change in the mass content of mullite and anorthite at above 1 000 ℃. For the blend ash, the mullite content in the ore composition increased, the amount of anorthite decreased at 1 000 ℃ with the increase of the proportion of low calcium anthracite, resulting in the increase of melting point of blend coal ash.