大庆油田致密油水平井压裂关键技术及建议

Key technologies and suggestions for horizontal well fracturing in tight oil reservoirs of Daqing Oilfield

针对大庆油田致密油储层横向发育不连续、非均质性强、天然裂缝不发育、纵向发育多薄层等特点,以“提产量、降成本、提效率”为目标,采用室内实验、数值模拟及现场试验相结合的方式,攻关形成了以“平面密切割与纵向穿层立体改造提产技术、变黏度滑溜水携砂降本技术、段内暂堵与可溶桥塞及连续油管水力喷射等配套提效工艺”为主的致密油水平井体积压裂关键技术。全面剖析了致密油储层改造技术在Ⅱ类储层效益建产、老井提效、生产制度完善3个方面面临的挑战,提出了3个致密油压裂关键技术攻关建议:①持续攻关Ⅱ类储层水平井压裂提产技术;②攻关完善压裂增能技术;③完善合理返排及生产制度。围绕这些关键技术进行攻关研究,对于大庆致密油经济高效开发具有重要意义。

Tight oil reservoirs in Daqing Oilfield have the characteristics of discontinuous transverse development,strong heterogeneity,lack of natural fractures and multiple thin layers in longitudinal development.With the goal of"increasing oil production,reducing cost and improving efficiency",the method of combining laboratory experiment,numerical simulation and field test is adopted.The key technologies for volumetric fracturing of tight oil horizontal wells have been developed,with the core of"close cutting in plane and longitudinal cross-layer fracturing to increase production,variable viscous slippery water carrying sand cost reduction,temporary plugging in the section,soluble bridge plug and coiled tubing hydraulic injection technologies".A comprehensive analysis is conducted on the challenges faced by tight oil reservoir stimulation technology in three aspects:the benefit construction of Class II reservoirs,the improvement of old-well efficiency,and the improvement of productive systems.Three key technical proposals for tight oil fracturing are put forward:①Continue to develop fracturing technology for horizontal wells in Class II reservoirs;②Tackle key problems to improve fracturing and energy enhancement technology;③Improve reasonable backflow and productive system.The research on these key technologies is meaningful for the economic and efficient development of tight oil reservoirs in Daqing Oilfield.