Study on differences of pore structure of typical soft and hard coal
刘彦伟张帅左伟芹韩红凯徐鹏
LIU Yanwei,Zhang Shuai,ZUO Weiqin,HAN Hongkai,XU Peng
河南理工大学 安全科学与工程学院中国计量大学 理学院
煤体孔隙结构研究主要侧重于某一种孔隙结构测定技术方法,而单一测定方法在原理上不能准确表征煤体多尺度孔裂隙结构特征。在分析压汞法、液氮吸附法、二氧化碳吸附法以及小角X射线散射法4种试验方法的试验原理、适用条件和煤体物性特征基础上,提出了基于数据融合的煤全孔径孔隙结构集成测定和表征方法。采用新方法从孔隙形状、孔容、比表面积、孔径分布4个方面,研究了2种不同变质程度软硬煤孔隙结构的差异性。结果表明:煤全孔径孔隙结构集成测定和表征方法融合了上述4种方法测定孔隙结构的优势,结果更可靠、合理;2种煤样的软煤总孔容大于硬煤,软硬煤大孔孔容所占比例最大,且两者阶段孔容的差异性主要在于中孔和大孔阶段,其中中孔差距最为明显。而软煤微孔孔比表面积远大于硬煤。构造作用对于高变质程度煤的中孔孔容发育影响最大,对于低变质程度煤的大孔孔容发育影响最大;构造作用对于低变质程度煤的微孔表面积影响较小。上述研究成果为开展煤体多尺度孔隙的瓦斯吸附、运移规律和机理研究奠定了物性基础。
The study of coal pore structure research mainly focuses on a certain pore structure measurement technology method, but a single measurement cannot accurately characterize the characteristics of the multi-scale pore and fissure structure of coal in principle. Based on the analysis of the test principles, applicable conditions and coal physical properties of four test methods are proposed: mercury intrusion, nitrogen adsorption, carbon dioxide adsorption and small angle X-ray scattering method. and an integrated measurement and characterization method of pore structure of coal with full pore size based on data fusion is formed. In this paper, the differences of pore structure of soft and hard coal with two different metamorphic degrees are analyzed by using a new method from the aspects of pore shape, pore volume, specific surface area and pore size distribution. The results show that the integrated measurement and characterization method for the full pore structure of coal combines the advantages of the above four methods to determine the pore structure, and the results are more reliable and reasonable;the total pore volume of soft coal is larger than that of hard coal, and the soft and hard coals have large pores, and the difference between the two stages is mainly in the mesopore and macropore stages, in which the gap between the middle pore is the most obvious.The specific surface area of micropore of soft coal is much larger than that of hard coal. Tectonic effecthas the greatest influence on the development of mesopore pore volume of high-metamorphic coal, and has the greatest influence on the development of macropore volume of low-metamorphic coal, while it has little effect on the micropore surface area of low metamorphic coal.The above research results lay a physical foundation for the study of gas adsorption and migration laws and mechanisms of multi-scale pores in coal.
孔隙结构压汞法液氮吸附法二氧化碳吸附法小角X射线散射
pore structure; mercury intrusion; nitrogen adsorption; carbon dioxide adsorption; small angle X-ray scattering
0 引言
1 试验
1.1 煤样的制备
1.2 压汞试验
1.3 液氮吸附试验
1.4 二氧化碳吸附试验
1.5 小角X射线散射试验
2 试验结果与分析
2.1 软硬煤进退汞曲线差异
2.2 液氮吸附曲线差异
2.3 小角X射线散射试验讨论
3 软硬煤全孔径差异性分析
3.1 软硬煤全孔径分析
3.2 软硬煤全孔表面积分析
4 结论
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会