Permeability experiments of pore structure in coal matrix

被引:0
|
作者
Liu Y.-Q. [1 ,2 ]
Hou J.-L. [1 ,2 ]
Zhang L. [1 ,2 ]
Fan S.-W. [1 ,2 ]
机构
[1] Mine Safety Technology Branch, China Coal Research Institute, Beijing
[2] National Key Lab of Coal High Efficient Mining and Clean Utilization, China Coal Research Institute, Beijing
来源
| 1600年 / China Coal Society卷 / 41期
关键词
Compression coefficient; Fracture; Permeability; Porosity; Stress sensitivity;
D O I
10.13225/j.cnki.jccs.2016.0151
中图分类号
学科分类号
摘要
Coal seam is typical double porosity medium, whose permeability is controlled by the structural parameters of pores and fractures. A unified mathematical model of porosity and permeability for gas flow in a double porosity medium was established. Lots of gas seepage phenomena in coal body were divided into three types: pore control, fracture control and pore-fracture combination control. With the gas seepage experimental data of six groups of coal samples and their test statistics of the porosity and fracture, the reasons of the permeability difference in the coal samples were discussed. The study found that the structural parameters of the pores and fractures determined the compression coefficient and permeability index of coal body, and then determined the type of gas seepage. The key factors affecting the permeability of coal seam were the density and the scale of pores and fractures. However, the stress sensitivity was almost impossible to be reflected in the micro pores because of the Van der Waals force between gas molecules and other particles. © 2016, Editorial Office of Journal of China Coal Society. All right reserved.
引用
收藏
页码:434 / 440
页数:6
相关论文
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