Research progress on methods for determining the permeability coefficient of coal seams
CHEN Xuexi
MA Jingyi
HU Jiaying
HAN Peixue
BI Ruiqing
SUN Jihong
LIU Zijian
Abstract：The permeability coefficient of coal seams serves as a crucial indicator for evaluating the difficulty of gas extraction,the effect-iveness of pressure relief in protective layers to enhance permeability,and the severity of coal and gas outburst hazards.This paper briefly reviews the development of coal seam permeability coefficient determination methods,focusing on the research progress and respective characteristics of laboratory methods,radial flow methods,gas pressure recovery curve methods,and gas injection methods.Analysis in-dicates that laboratory methods offer advantages such as simplicity and low cost,but struggle to replicate underground conditions per-fectly;they may serve as important supplementary tools for field measurements in the future.The radial flow method,though widely ap-plied in the field,suffers from cumbersome calculation steps and discontinuous data values.Despite various optimization strategies pro-posed by scholars,no unified calculation standard has been established.The gas pressure recovery curve method offers strong in-situ test-ing capabilities and intuitive data interpretation,but it is significantly affected by plugging quality and pressure measurement accuracy,making it difficult to accurately capture the mid-term radial flow slope segment.The gas injection method demonstrates promising poten-tial in complex seepage coal seams,offering a viable approach for anisotropic permeability determination.However,its field measurement process is complex,and its on-site testing accuracy and data stability are limited.Future research on coal seam permeability coefficient de-termination should focus on several key areas:developing unified theoretical models that integrate multi-field coupling and multi-scale analysis;establishing industry standards and computational specifications for the radial flow method;enhancing the accuracy of pressure recovery curve identification and analysis;optimizing gas injection medium selection and test point layout;and improving field monitor-ing precision and automation levels.
Keywords：coal seam permeability coefficientradial flow methodgas pressure recovery curvegas injection methodresearch progress
Publication Date：2026-01-31
Online Publishing Date：2026-03-12(First online date of this platform, not the publication date of the document)
Pages：12( 230-241 )