低渗透储层多级转向压裂技术

Multi-Stage Deflective Fracturing Technology for Low Permeability Reservoir

周丹 熊旭东 何军榜 董波 贺勇

ZHOU Dan XIONG Xudong HE Junbang DONG Bo HE Yong

中国石油新疆油田分公司百口泉采油厂，新疆克拉玛依 834000 中国石油新疆油田分公司工程技术处，新疆克拉玛依 834000 新疆克拉玛依市井下作业公司，新疆克拉玛依 834000

Baikouquan Oil Production Plant, PetroChina Xinjiang Oilfield Branch, Karamay, Xinjiang, 834000, China Engineering and Technology Department, PetroChina Xinjiang Oilfield Branch, Karamay, Xinjiang, 834000, China Xinjiang Karamay Underground Operation Company, Karamay, Xinjiang, 834000, China

低渗透储层采用常规压裂工艺改造后，存在压裂改造波及体积小、有效期短和改造效果差等问题。为了提高低渗透油气田增储上产水平，根据油藏地质特点和多级转向压裂起裂机理，研制了溶解度高、溶解速度快、残渣含量少和对储层渗透率伤害小的高性能水溶性暂堵剂，并形成了多级转向压裂技术。在地层压开裂缝后，实时向地层中加入该高性能水溶性暂堵剂形成瞬时暂堵，提高缝内净压力，通过暂堵转向产生微裂缝和分支缝，从而形成复杂的网络裂缝，实现体积改造的目的。多级转向压裂技术在新疆油田X区块应用后，产油量大幅提高，单井日增油量为常规压裂井的2.0倍；稳产时间长，有效期较常规压裂井延长50%。多级转向压裂技术解决了低渗透砾岩储层改造难题，为低渗透砾岩储层开发后期稳产提供了新的技术手段。

Problems such as small sweeping volume, short longevity and poor fracturing stimulation effects are common when conventional fracturing technology is adopted in low permeability reservoirs. In order to improve the production of low-permeability oil and gas fields, a high-performance temporary bridging agent with high solubility, fast dissolution rate, low residue content and low damage to permeability was developed with deployment using an innovative multi-stage deflective fracturing technology. These were developed based on geological characteristics of the reservoir and the initiation mechanism of multi-stage deflective fracturing. When the formation is fractured, a temporary bridging agent is added in the frac fluid in real time to form instantaneous temporary bridging at the opening of fractures. These result increased net pressure within fractures, and generate microfractures and branch fractures, thus forming complex network fractures and achieving the goal of volumetric stimulation. After the application of multi-stage deflective fracturing technology in Block X of the Xinjiang Oilfield, oil production dramatically increased, and daily oil increment per well is 2.0 times that of wells with conventional fracturing technique. In addition, this method results in a longer stable production period, and the longevity is 50% higher than that with conventional fracturing. The application of multi-stage deflective fracturing technology can solve the problem of reservoir stimulation in low permeability conglomerate reservoirs and provided a new technical mean for achieving stable production in the late production period of low permeability conglomerate reservoirs.

中国石油天然气股份有限公司油气开发重大科技项目“新疆油田和吐哈油田勘探开发关键技术研究与应用”课题14“降本提效试油及采油关键技术研究与应用”（编号：2017E-0414）资助

https://doi.org/10.11911/syztjs.2019077