Research on the application technology of three-stage pre-drainage for outburst elimination in areas of coal and gas outburst-prone mines
YANG Hongwei
YAN Honghu
JIN Qing
LU Xiaorong
Abstract：With the increasing depth of coal mining,the prevalence of coal and gas outburst-prone mines has risen,accompanied by significant challenges such as high gas content and difficulties in gas drainage.This pa-per proposes a three-stage pre-drainage method aimed at mitigating outbursts.By employing an integrated model of "surface wells+directional long boreholes+conventional boreholes",this approach effectively re-duces the gas content within coal seams.Engineering tests conducted at the Jinsheng Yong'an Hongtai Coal Mine demonstrate that the system significantly enhances drainage efficiency:surface wells achieved a cumula-tive gas extraction volume of 70,205,192 m3,while directional long boreholes further improved pre-drainage effectiveness,and conventional boreholes served as a supplementary means,effectively covering local areas not reached by directional drilling and eliminating extraction blind zones.The gas pre-drainage rate exceeded 50％,with residual gas content and pressure reduced to 5.7223 m3/t and 0.178 MPa,respectively.Compared to pre-drainage conditions,these values represent decreases of 54％and 44％,respectively.This method has proven effective in controlling coal and gas outburst hazards,thereby ensuring safe production in outburst- prone mines.
Keywords：three-stage pre-drainagecoal and gas outburstregional outburst eliminationgas drainage
Publication Date：2026-02-28
Online Publishing Date：2026-03-12(First online date of this platform, not the publication date of the document)
Pages：7( 99-105 )