黔西北多层薄煤储层暂堵转向压裂技术应用

黔西北地区煤层具有层数多、单层薄、非均质性强等特点，为探索经济高效的煤储层压裂改造技术，进行了煤层纵向暂堵转向压裂技术应用研究。结合转向压裂技术特点，从煤层压裂裂缝形态、力学屏蔽、射孔井段和煤体结构4个方面进行了适用性分析。为确保暂堵转向压裂能够更大限度沟通煤层，实现煤层均匀改造和压裂水平缝较长延伸，对暂堵材料和用量进行了优化组合。同时，在黔西北地区优选2口煤层气井分别开展了机械暂堵和化学暂堵转向压裂现场应用试验。结果表明，采用化学暂堵剂组合模式基本能够满足纵向（层间）暂堵转向压裂工艺的要求，取得了较好的应用效果，为贵州多煤层与薄煤层压裂改造提供了有效的技术支撑。 

Application of temporary plugging and diverting fracturing technology for multiple and thin coal reservoir in northwestern Guizhou

In the northwest of Guizhou Province, the coal seam has multiple layers, is thin in single layer, heterogeneous and so on, in order to explore the economic and efficient coal seam fracturing technology, application technique of temporary plugging and longitudinal diverting fracturing for coal seam is studied. Combined with the characteristics of diverting fracturing technology, this paper analyzed the applicability from four aspects:coal seam fracture form, mechanical shielding, perforation interval and coal structure. In order to ensure that the temporary plugging and diverting fracturing can link up more coal seams to achieve homogeneous transformation of coal seam and fracturing horizontal seam for longer extension, we optimize the combination of temporary plugging agent and the amount of materials. Meantime, two CBM wells were selected to carry out mechanical and chemical temporary plugging and diverting fracturing field application test. The results show that the combination mode of chemical temporary plugging agent can meet the requirements of longitudinal(interlayer)diverting fracturing process, and obtain good application effect, which provides effective technical support for the fracturing reformation of the thin coal reservoir in Guizhou.