Optimization research on gas extraction technology from drilling holes in extra thick coal seam
ZHANG Hongjie
Abstract：Aiming at the law of gas occurrence and effective prevention and control in extra-thick coal seams,taking the 8119 working face of Tashan Coal Mine as the engineering background,the experi-mental determination of gas basic parameters,the field test of effective gas extraction radius and the numerical simulation method are comprehensively used,and the field verification is further carried out through the gas extraction effect.The gas adsorption constant a of the coal sample in the 8119 work-ing face is 19.997 m3/(t·r),and the b value is 0.359 MPa-1.The maximum coal seam gas content is 4.87 m3/t,and the maximum coal seam gas pressure is 0.22 MPa.The permeability coefficient of coal seam is 11.29 m2/(MPa2·d);the initial emission intensity q0 of the borehole is 4.92 m3/min,and the attenuation coefficient α of the borehole gas flow is 0.066 d-1.When the effective extraction radius of gas is 1.5 m and the extraction time is 138 d,the optimal gas extraction effect is achieved.This con-clusion is consistent with the field verification and evaluation results.
Keywords：extra thick coal seamdrilling and extraction of gasthe extraction radiusnumerical simula-tion
Publication Date：2025-10-01
Online Publishing Date：2025-09-22(First online date of this platform, not the publication date of the document)
Pages：6( 41-46 )