摘要
Abstract
To solve the problem of high risk of mine gas outburst and multiple occurrences of gas dynamic phenomena in Qiyuan Coal Industry,based on Darcy's law and Mohr-Coulomb criterion,a water sand fracturing outburst prevention drainage technology is studied and proposed to be used.Through large liquid volume water sand fracturing in surface vertical wells,complex crack networks are formed,which changes the stress state of coal bodies and improves the permeability of coal seams.Implement casing large displacement injection fracturing process,using single-stage fracturing,high pressure,long-term continuous injection,multi-stage progressive sand addition and other methods.The effect test shows that after fracturing,the static pressure at the bottom of the well improves by 14.3%,the dynamic pressure increases by 15.8%,the permeability increases by 56%,and the daily average gas production increases by 232%.This technology significantly reduces the coal seam gas content,reduces the risk of gas outburst,improves the safety coefficient of the mine,creates favorable conditions for subsequent coal mining work,and brings considerable economic benefits at the same time.关键词
煤矿/防突/水砂压裂/瓦斯抽采Key words
coal mine/outburst prevention/water sand fracturing/gas drainage分类
矿业与冶金
