中文摘要：

本文研究了HCl-HF—HCl方法脱灰对低灰煤粉性质的的影响。研究发现，酸处理不仅使煤的灰分脱除，也使其挥发分降低，煤变质程度越低，挥发分降低幅度越大；通过对脱灰滤液的检测，发现脱落的有机质主要是短链烷烃及其同系物，也有少量的含氧物质；酸处理后煤粉中金属离子也将全部脱除；燃烧特性研究发现，煤粉脱灰后高变质程度煤反应活性提高，低变质程度煤反应活性下降，取决于有机质和金属离子脱除与比表面积增加之间的平衡。因此，化学脱灰不能证明矿物对煤粉燃烧的影响。

英文摘要：

In this paper the influence of HCl-HF-HCl treatment on the properties of pulverized coals with low ash content was studied. After acid treatment the mineral matters were all removed; besides, the volatile matter contents of all the five coals were found decreased. The lower the rank, the more prominent the decrease. The filtrates from the acid treatment were analyzed and the organic matters found were mainly low molecular alkanes and some oxygenic compounds. The metallic ions were all removed after acid treatment. The combustion characteristics study showed that after the treatment the combustion reactivity of coals with high rank was all increased and those of coals with low rank was decreased, apparently the result of a balance between the removal of organic matter, metallic ions and increase of surface area. It was concluded that acid treatment can be used to prove the effects of mineral matter on the combustion of pulverized coals.