摘要
为了提高顺煤层钻孔瓦斯抽采效果,在分析井下煤层水力压裂技术发展现状及其增透机理的基础上,结合定向长钻孔施工技术与煤层水力压裂增透强化抽采技术,提出了顺煤层定向长钻孔裸孔坐封、水力压裂增透技术工艺。鉴于赵固二矿二1煤层中等偏硬、厚度大、瓦斯含量高等特征,选择该矿井二1煤层进行长钻孔整体压裂试验。结果表明:采用煤层长钻孔孔内封隔器裸孔坐封方式能够满足赵固二矿水力压裂煤层段密封需要;注水压裂过程压力上升平稳,泵压和流量达到设计要求;工具串回收过程无塌孔和卡阻现象,顺层长钻孔孔内封隔器裸孔坐封和压裂工艺达到预期目标;整体水力压裂影响半径最大达到38 m(单侧),压裂钻孔百米钻孔瓦斯抽采量比常规顺层钻孔有了较大提升。
In order to improve the gas drainage effect along the coal seam,based on the analysis of the development status of underground hydraulic fracturing technology and the principle of hydraulic fracturing permeability enhancement,a coal seam permeability enhancement technology along the coal seam with the directional long-hole hydraulic fracturing was put forward by combining the directional long-hole drilling technology with the coal seam hydraulic fracturing permeability enhancement drainage technology. In view of the characteristics of moderate degree of hardness,thick coal seam and high gas content in Zhaogu No. 2 coal mine,the engineering test of long borehole overall fracturing of coal seam was carried out. The results showed that the seam sealing requirement of hydraulic fracturing coal seam in Zhaogu No. 2 coal mine could be satisfied by bare hole sealer;the pressure rose steadily in the process of water injection fracturing,and the pump pressure and flow met the design requirements;there was no hole collapse and blocking phenomena in the recovery process of tool string. Expected goals of the sealing and fracturing technology of borehole sealer along the seam could be achieved. The maximum influence radius of the whole hydraulic fracturing was 38 m (unilateral),and the gas drainage rate of the 100-meter borehole was much higher than that of the conventional bedding borehole.
作者
龙威成
赵乐凯
陈冬冬
赵继展
LONG Weicheng;ZHAO Lekai;CHEN Dongdong;ZHAO Jizhan(Xi’an Research Institute,China Coal Technology&Engineering Group Corp.,Xi’an 710077,Shaanxi,China;Zhaogu No.2 Coal Mine of Jiaozuo Coal Group Xinxiang Energy Co.,Ltd.,Xinxiang 453600,Henan,China)
出处
《河南理工大学学报（自然科学版）》
CAS
北大核心
2019年第3期10-15,共6页
Journal of Henan Polytechnic University（Natural Science）
基金
国家科技重大专项项目(2016ZX05045-002)
中煤科工集团西安研究院有限公司科技创新基金重点资助项目(2017XAYZD06
2017XAYZD19
2018XAYZD09)
关键词
水力压裂
煤层增透
顺层长钻孔
裸孔坐封
瓦斯抽采
hydraulic fracturing
coal seam permeability enhancement
long borehole along seam direction
bare hole sealer
gas extraction
