涪陵页岩气水平井高效压裂技术及应用

针对涪陵页岩气田国家级页岩气示范区水平井储层特点,结合套管固井完井方式,为实现有效改造体积最大化,改造体积内裂缝复杂程度最大化,通过缝网压裂工艺、低成本高效材料体系、返排液重复利用等技术研究,形成了一套适合于涪陵页岩气水平井高效压裂技术。其中缝网压裂工艺实现了形成复杂裂缝网络的压裂目标,高效低成本减阻水压裂液体系,满足连续混配施工要求,成本较国外减阻水体系降低20%以上,现场测试减阻率高达74.5%,返排液重复利用技术实现返排液零排放。截至2017年12月,集成技术累计现场应用330井次,压裂5300段,工艺成功率97%,平均无阻流量38.5×10~4 m^3/d,增产增气效果显著。

Efficient Fracturing Technology and Application Forhorizontal Well of Shale Gas in Fuling

In view of the characteristics of horizontal well reservoirs in the national shale gas demonstration area of the Fuling shale gas field, combined with casing cementing and completion methods, in order to maximize the effective transformation volume, the complexity of the crack within the volume is maximized. Fracturing technology, low-cost and high-efficiency material system, and back-discharge liquid reuse technology have formed a set of high-efficiency fracturing technology suitable for the horizontal wells of Fuling shale gas. The fracturing process has realized the target of complex fracture network. The high-efficiency and low-cost drag reduction hydraulic fracturing fluid system meets the requirements of continuous compounding construction, and the cost is reduced by more than 20% compared with the foreign water-reducing water system. The on-site test drag reduction rate is as high as 74.5%, and the return-discharge liquid reuse technology realizes zero liquid emission. As of December 2017, the integrated technology has accumulated 330 wells on site, fracturing 5 300 segments, with the process success rate of 97% and the average unobstructed flow of 385 000 cubic meter per day. The effect of increasing production and increasing gas is significant.