虽然新能源技术发展迅速,但未来很长一段时间我国能源主体仍以煤炭为主。高钙高铁煤是我国重要的煤炭资源,分布广泛,其灰熔融温度较低,不可直接应用于气流床气化炉。因此,以高钙高铁煤(MO)为研究对象,选择高硅铝煤(Y4)调控高钙高铁煤(MO)的灰熔融温度(TAF)。利用X射线衍射仪(XRD)、傅里叶变换红外光谱仪(FT-IR)、拉曼光谱仪(Raman)和FactSage热力学软件探讨了高硅铝煤调控高钙高铁煤灰熔融特性的变化机制。研究表明,随Y4配比增加,混合灰样的灰熔融温度逐渐增加,且当Y4混配比例为40%~50%时,混合灰样的流动温度(TF)为1354~1389℃,TF符合气流床气化炉液态排渣要求;XRD和FactSage结果表明,随Y4含量增加,低熔点矿物质逐渐消失,钙长石等稳定硅铝酸盐矿物质的生成是导致灰熔融温度升高的主要原因,从三相图中发现随Y4混配比例的增加,灰样中的矿物质由黄长石明显转变为钙长石;FT-IR显示随Y4配比的增加,灰样中的Si—O向高频区移动,且在900~1000cm-1形成一个较宽的吸收峰,结合XRD,判断该吸收峰为钙长石;从硅酸盐角度分析,引入参数R(R表示Si—O—A的变化程度),随Y4含量增加,灰样中R呈阶梯状增加,导致网络聚合度增加,灰熔融温度增加。

Although new energy technologies are developed rapidly, coal will still be the main energy source in China for a long timeto come. High calcium-iron coal is an important coal resource in China, which is widely distributed. Its ash fusion temperature TAF is lowand cannot be directly applied to entrained flow gasifier. Therefore, taking high-calcium-iron coal (MO) as the research object, high sil⁃icon-aluminum coal (Y4) was selected to regulate its ash fusion characteristics. The regualtion mechanism of ash fusion characteristicswas discussed by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Raman Spectroscopy (Raman) and Fact⁃Sage thermodynamic software. The results show that with the increase of Y4 ratio, the TAF of the mixed ash sample increases gradually.When the mixing ratio of Y4 is 40%-50%, the flow temperature of mixed ash sample is 1 354-1 389 ℃ , which met the requirements forslag tapping of the entrained-flow gasifier. The XRD and FactSage results show that with the increase of Y4 content, the gradual disap⁃pearance of low melting point minerals and the formation of stable aluminosilicate minerals (like anorthite) mainly result in the increase ofTAF. From the three-phase diagram, it is found that with the increase of Y4 mixing proportion, the minerals in the ash sample changefrom melilite to anorthite. FT-IR results show that with the increase of Y4 ratio, the Si—O in the ash sample moves to the high frequencyregion, and forms a broader absorption peak between 900-1 000 cm-1. Combined with XRD result, it is judged that the absorption peak isanorthite. From the perspective of silicate melts, the parameter R is introduced to represent Si—O—A. With the increase of Y4 content,the R in the ash sample increases in a " stepped" pattern, leading to an increase in network polymerization degree, which explains the in⁃crease in TAF.

0 引言

1 试验

   1.1 试验原料分析

   1.2 高温灰样制备

   1.3 灰熔融温度测试

   1.4 灰样分析方法

   1.5 热力学平衡计算及黏度预测

2 结果与讨论

   2.1 Y4对MO混合灰样灰熔融温度的影响

   2.2 混合灰样的矿物质变化

   2.3 混合灰样的红外光谱分析

   2.4 混合灰样的拉曼光谱分析

   2.5 混合灰样的热力学平衡计算

3 结论