利用XRD分析高温下淮南煤灰矿物质变化

Study of huainan coal ash mineral variation under high temperature with XRD

利用X射线衍射分析四种淮南煤在不同温度下煤灰矿物组成变化。结果表明:淮南煤中主要晶体矿物有高岭石、石英、方解石、黄铁矿等,高岭石类矿物含量越高,煤灰熔点越高;方解石和黄铁矿含量越高,煤灰熔点越低。煤灰中主要晶体矿物有石英、硬石膏、赤铁矿等,硬石膏和赤铁矿含量越大煤灰熔点越低。随着温度的升高,煤灰中石英、硬石膏、赤铁矿等结晶矿物含量逐渐减少,生成新的矿物质,莫来石的生成是导致淮南煤灰熔点高的主要原因,钙长石起到降低煤灰灰熔点的作用。

The content variation of four kinds of Huainan coal ash mineral under different temperatures was analyzed with X-ray diffraction （XRD）. The test results showed that Huainan coal samples generally include kaolinite, quartz, Calcite, pyrite. The kaolinite in coal can improve the ash melting temperature; The calcite and pyrite in coal can reduce the ash melting temperature. The mineral phases of coal ashes generally include quartz, hematite, anhydrite. The higher the Anhydrite and Hematite content is, the lower the ash melting temperature is. As the temperature increases, the content of quartz, anhydrite, Hematite in coal ash will decrease in reducing conditions and some new mineral phases are formed during the heating processes. The content of mullite formed in the heating process is the main reason of ash melting temperature high of coal samples. Anorthite at high temperature can lower the ash fusion temperature effectively.