Image-based quantitative probing of 3D heterogeneous pore structure in CBM reservoir and permeability estimation with pore network modeling
Peng Liu1
Yulong Zhao1
Zhengduo Zhao1
Huiming Yang2
Baisheng Nie1
Hengyi He1
Quangui Li1
Guangjie Bao1
1.State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400030,China;College of Resources and Safety Engineering,Chongqing University,Chongqing 400030,China2.State Key Laboratory of Gas Disaster Detecting,Preventing and Emergency Controlling,Chongqing 400037,China;China Coal Technology Engineering Group Chongqing Research Institute,Chongqing 400037,China
摘要：Coalbed methane(CBM)recovery is attracting global attention due to its huge reserve and low carbon burning benefits for the environment.Fully understanding the complex structure of coal and its transport properties is crucial for CBM develop-ment.This study describes the implementation of mercury intrusion and μ-CT techniques for quantitative analysis of 3D pore structure in two anthracite coals.It shows that the porosity is 7.04％-8.47％and 10.88％-12.11％,and the pore connectivity is 0.5422-0.6852 and 0.7948-0.9186 for coal samples 1 and 2,respectively.The fractal dimension and pore geometric tortuos-ity were calculated based on the data obtained from 3D pore structure.The results show that the pore structure of sample 2 is more complex and developed,with lower tortuosity,indicating the higher fluid deliverability of pore system in sample 2.The tortuosity in three-direction is significantly different,indicating that the pore structure of the studied coals has significant anisotropy.The equivalent pore network model(PNM)was extracted,and the anisotropic permeability was estimated by PNM gas flow simulation.The results show that the anisotropy of permeability is consistent with the slice surface porosity distribution in 3D pore structure.The permeability in the horizontal direction is much greater than that in the vertical direc-tion,indicating that the dominant transportation channel is along the horizontal direction of the studied coals.The research results achieve the visualization of the 3D complex structure of coal and fully capture and quantify pore size,connectivity,curvature,permeability,and its anisotropic characteristics at micron-scale resolution.This provides a prerequisite for the study of mass transfer behaviors and associated transport mechanisms in real pore structures.
机标关键词：permeabilityquantitativestructuremodelingnetworkwithestimationheterogeneous
论文发表日期：2024-10-28
在线出版日期：2025-08-15（本平台首次上网日期，不代表文献的发表时间）
页数：21( 121-141 )
英文信息