储层改造是获得低渗透煤层气井高产的重要手段，虽然我国深部煤层气资源丰富，但是由于煤储层渗透率低，面临着不同煤层气地质条件下的储层改造技术适应性差的困境。以沁水盆地长治北部地区为例，介绍了研究区地质概况和开发模式，分析了4种深部煤层气井水力压裂工艺技术及应用效果。结果显示以水平井为主要井型、实现压裂后井间干扰提产是规模化开发深部煤层气资源的主要途径。光套管压裂技术可实现大规模压裂，但容易造成储层污染，且可调性较差导致压裂效果偏差;连续油管压裂技术自动化程度和作业效率高，是目前的主流压裂技术，但是配套设施要求较高、成本高;常规油管压裂技术可实现射孔、压裂、封隔一体化作业，且射流效应定向性强，但是不能够带压作业，容易造成压力激动、压后堵前。为此，自主开发了常规油管带压压裂新技术。该技术以常规油管压裂技术为基础，在井口和井下油管内安装稳压装置控制压裂过程中油管内外的带压状态，配合钢丝绳打捞装置，优化上提下放程序，从而实现带压拖动压裂作业。该技术压裂施工曲线以压力平稳型为主，能够形成连续和平直的压裂裂缝通道，减少储层伤害;微地震监测显示压裂裂缝两翼长达70 m;试验井日产气量达4 000 m3以上;同时节约了作业成本，提高了压裂效率。

Reservoir reconstruction is an important means to improve the productivity of coalbed methane (CBM) wells with low permeability.Although China is rich in deep coalbed methane resources,it is faced with the difficulty of poor geological adaptability of reservoir reconstruction technology under different geological conditions of CBM reservoir due to low permeability.Taking the northern area of Changzhi in Qinshui Basin as an example,this paper introduces the geological situation and development mode of the study area,and analyzes four kinds of deep CBM well hydraulic fracturing technology and application effect.The result shows that the main approaches of large-scale development of deep CBM resources are characterized by horizontal wells and inter-well interference after fracturing.The casing fracturing technology can achieve large-scale fracturing,but it is easy to cause reservoir pollution and poor adjustability.The coiled tubing fracturing technology has high degree of automation and operation efficiency,which is the mainstream fracturing technology at present,but the cost and supporting facilities are high.The conventional tubing fracturing technology can realize the integration of perforation,fracturing and packer operation,and the jet effect is highly directional,but it cannot operate under pressure,which is easy to cause pressure excitation and “opening the back and plugging the front”.Therefore,the authors have independently developed a new fracturing technology of conventional tubing with pressure.The technology is based on conventional tubing fracturing.The pressure stabilizing devices are installed in the wellhead and downhole tubing to control the pressure state inside and outside the tubing during the fracturing process.With the wire rope fishing device,the lifting and lowering procedure is optimized,so as to realize the pressure drag fracturing operation.The fracturing operation curve of this technology is mainly of stable pressure type,which can form a continuous and straight fracture channel,and reduce reservoir damage.Micro-seismic monitoring shows that the two wings of the fracture are 70 m,and the daily gas production of the test well is more than 4 000 m3.At the same time,the operation cost is saved and the fracturing efficiency is improved.

1 研究区煤层气勘探开发概况

   1.1 煤储层地质特征

   1.2 煤层气开发特点

2 水平井对煤储层改造机理

3 深部煤层气水平井水力压裂技术

   3.1 光套管压裂技术

   3.2 连续油管压裂技术

   3.3 常规油管压裂技术

4 带压油管压裂新技术

   4.1 技术流程

   4.2 压裂效果

5 结论