中文摘要：

褐煤腐植酸含量高，腐植酸中含有多种活性基团，在工业、农业、畜牧业等领域有多种用途。褐煤直接燃烧利用率不大，因此在开发利用褐煤资源前对其进行腐植酸抽提是一种较好的提质方式。本文采用碱浸法对褐煤进行腐植酸的抽提，研究了煤样粒度、抽提条件等因素对腐植酸抽提率的影响，以及干燥的原煤、腐植酸抽提残煤和脱灰煤的水分复吸性能。结果表明：粒度在0．2mm以下的煤样，在超声波条件下抽提腐植酸效果较好；抽提残煤水分复吸率明显高于原煤，但将抽提残煤脱灰处理后，水分复吸率有明显下降，且与原煤脱灰后吸水性能相近，说明抽提残煤的吸水性与煤的孔隙率及表面的极性官能团有关，特别是碱浸法抽提腐植酸时生成的强吸水性羧酸盐类对抽提残煤吸水性有显著影响。

英文摘要：

The lignite is featured with a high content of humic acid that contains various active groups, and has many uses in industry, agriculture, animal husbandry and other fields. The utilization rate of lignite＇s direct burning is not big, so before the exploitation and utilization of lignite resources, the extraction of humic acid is a better upgrading way. Using the alkali leaching method for lignite humic acid extraction, the influence of the particle size, reaction medium on the humic acid extraction ratio was studied, as well as the moisture re-adsorption characteristics of the dry raw coal, extraction coal and demineralized coal in a certain simulation conditions. The results show that the coal particle size under 0.2 mm in the ultrasonic is good for the extraction of humic acid. And the moisture re-adsorption ratio of extraction coal is significantly higher than that of raw coal. The moisture re- adsorption ratio declines obviously after the demineralization of extraction coal, closing to that of raw coal after demineralized. So the water absorption characteristic of extraction coal is relevant to the porosity and surface polar functional groups of coal. Especially the strong water imbibition carboxylate generated in the alkali leaching extraction of humic acid has a significant effect on the water absorption characteristic of extraction coal.