1.School of Safety Engineering, China University of Mining and Technology, Xuzhou , China; 2.School of Architecture and Environment, Ningxia Institute of Science and Technology, Shizuishan , China; 3.MOE Key Lab of Mine Gas and Fire Prevention and Control, China University of Mining and Technology, Xuzhou, China

煤储层中孔隙的发育特征控制着煤中瓦斯的吸附解吸与扩散性能,为了研究不同变质程度硬煤的孔隙结构特征差异,采用压汞法和液氮吸附法相结合的手段,对园子沟矿3煤、窑街三矿2煤和卧龙湖矿8煤三种,煤样进行了全孔径孔隙结构分布测定,利用分形理论对比分析了不同变质程度硬煤孔隙结构特征。研究结果表明:园子沟、窑街和卧龙湖三种不同变质程度硬煤均含有丰富的开放孔隙特征,随着变质程度增大,煤的孔隙度呈现高-低-高的变化规律;园子沟和卧龙湖煤样孔形多以墨水瓶、锥形孔等孔形为主,窑街煤样孔形多以圆筒形孔为主;而对比孔隙结构分形维数可知,园子沟煤样孔隙分形维数最大,卧龙湖煤样次之,窑街煤样孔隙结构相对简单,也呈现出高-低-高的变化规律。

The development features of the pores in the coal reservoir would control the adsorption-desorption and diffusion performances of the gas in the coal. In order to study the pore structure feature differences of the hard coal with different metamorphic grade, a means combined with mercury intrusion method and liquid nitrogen adsorption method was applied to measure the full pore diameter and pore structure distribution of three hard coal samples from No.3 seam of Yuanzigou Coal Mine, No. 2 seam of Yaojie No. 3 Mine and No. 8 seam of Wolonghu Mine. A fractal theory was applied to compare and analyze the pore structure of the hard coal with different metamorphic grade. The study results showed that the three different metamorphic grade hard coal from Yuanzigou, Yaojie and Wolonghu would all have rich opened pore features. With the metamorphic grade increased, the coal porosity would have a high-low-high variation law. The pore of the coal samples from Yuanzigou, Yaojie and Wolonghu would be ink bottles and taper holes mainly. The pore of Yaojie coal samples was mainly in a cylindrical pore. In comparison with the fraction dimension of the pore structure, the pore fraction dimension of Yuanzigou coal sample would be the max and the pore fraction dimension of Wolonghu coal sample would be second. The pore structure of Yaojie coal sample would be relatively simple and also would have a high-low-high variation law.

国家自然科学基金面上资助项目(51674252)；国家重点研发计划资助项目(2016YFC0801406)；江苏高校“青蓝工程”资助项目(苏教师[2016]15号)；江苏省高校优秀中青年教师和校长境外研修计划资助项目(苏教办师[2015]7号)；