摘要
坦家冲煤矿2463区域瓦斯抽采钻孔底板岩层段裂隙发育,主采的6煤坚固性系数仅为0.17,瓦斯压力1.62 MPa,瓦斯含量18.38 m^(3)/t,煤层透气性系数0.002242~0.037755 m^(2)/(MPa·d)。就此类工程地质条件的瓦斯抽采问题,根据圆形钻孔周边塑性区域扩展深度理论和瓦斯解吸方法的新进理论及技术研究成果,针对岩层段钻孔裂隙发育的特点,实施了“两堵一注”+大长度封孔+带压封孔注浆的气密性保障措施,针对煤层段钻孔低透气性的特点确定并实施了水力造穴增透技术。综合技术方案实施后,各钻孔连续抽采115 d后的瓦斯浓度仍然能保持在35.6%左右,而之前的钻孔抽采10 d内瓦斯浓度即接近于0。
The cracks in the floor rock layer section of the gas extraction drilling holes in the 2463 area of Tanjiachong Coal Mine are developed.The firmness coefficient of the main 6 coal seams is only 0.17,the gas pressure is 1.62 MPa,and the gas content is 18.38 m^(3)/t.The permeability coefficient of coal seams ranges from 0.002242 to 0.037755 m^(2)/(MPa·d).Regarding the gas extraction problem under such engineering geological conditions,based on the new theories and technological research results of the plastic zone expansion depth theory and gas desorption method around circular boreholes,a gas tightness guarantee measure of"two blockages and one injection",large length sealing and pressure sealing grouting has been developed and implemented in response to the characteristics of the crack development in the rock layer section boreholes.In response to the low permeability of the coal seam section boreholes,hydraulic hole making and permeability enhancement technology has been determined and implemented.After the implementation of the comprehensive technical plan,the gas concentration of each drilling hole can still be maintained at around 35.6%after 115 days of continuous extraction,while the gas concentration of the previous drilling hole was close to 0 within 10 days of extraction.
作者
饶高
Rao Gao(Hunan Coal Industry Co.,Ltd.,Changsha 410118,China)
出处
《能源与环保》
2023年第7期43-49,共7页
CHINA ENERGY AND ENVIRONMENTAL PROTECTION
基金
教育部重点实验室开放基金项目(20211001)。
关键词
瓦斯抽采
抽采钻孔气密性
水力造穴增透
带压封孔注浆
gas extraction
gas tightness of pumping boreholes
hydraulic cavitation and penetration enhancement
pressurized hole sealing grouting
作者简介
饶高(1979—),男,湖南长沙人,高级工程师,工程硕士,2007年毕业于湖南师范大学,现任湖南省煤业集团副总经理。
