新疆油田深层致密砂岩气藏增产改造工艺技术研究  

Research on production transformation technology for deep tight sandstone gas reservoirs in Xinjiang Oilfield

作　　者：李磊 马春祥 张传亮 周海峰 杨鹏[2] 杨震[1] Li Lei;Ma Chunxiang;Zhang Chuanliang;Zhou Haifeng;Yang Peng;Yang Zhen(Downhole Operation Company of Qinghai Oilfield,Dunhuang 736200,China;Exploration Division of Qinghai Oilfield,Dunhuang 736200,China)

机构地区：[1]青海油田井下作业公司,甘肃敦煌736200 [2]青海油田勘探事业部,甘肃敦煌736200

出　　处：《能源与环保》2024年第7期150-155,共6页CHINA ENERGY AND ENVIRONMENTAL PROTECTION

摘　　要：新疆油田深层非常规致密砂岩储层具有埋藏深、异常高压、储层破裂压力高、地温高、低孔低渗、非均质性强、横向储层厚度变化大、纵向分布多等特点,储层压开成功率低、加砂困难,增产改造工艺技术面临极大挑战。针对该区块致密砂岩储层改造难点,优化形成了不同储层类型的针对性改造工艺技术:Ⅰ类储层采用“重晶石解除+酸化”工艺,解除重晶石污染堵塞、溶解裂缝内钙质,疏通天然裂缝系统;天然裂缝不同程度发育的Ⅱ、Ⅲ类储层采用缝网压裂工艺,前置液降低储层温度并激活天然裂缝系统、主体压裂液携砂形成高导流能力的主裂缝网络系统。对于储层厚度大、笼统改造无法实现巨厚储层的纵向均匀改造,则采用分层改造工艺。针对层间应力差为2~5 MPa的井,优选暂堵软分层工艺,缝网压裂采用“粉末+陶粒”不同粒径组合的暂堵软分层工艺;针对层间应力差大于5 MPa,采用机械分层改造工艺,若2个封隔器之间的跨度大于60 m,采用机械分层+软分层复合分层工艺。配套完善了以超级瓜尔胶稠化剂为主的基础压裂液体系,支撑剂选取40~70目粒径的陶粒,配套暂堵转向材料主要有可降解纤维、纤维粉末及颗粒暂堵剂等。形成的深层致密砂岩气藏的针对性储层改造工艺技术对探索非常规致密砂岩气藏储层改造技术具有重要借鉴意义。The deep unconventional tight sandstone reservoirs in Xinjiang Oilfield are characterized by deep burial,abnormal high pressure,high reservoir fracture pressure,high geothermal temperature,low porosity and permeability,strong heterogeneity,large lateral reservoir thickness changes,and multiple vertical distributions.The success rate of reservoir fracturing is low,and sand addition is difficult.The production and transformation process technology faces great challenges.In response to the difficulties in the transformation of tight sandstone reservoirs in this block,targeted transformation technogy for different reservoir types were optimized and formed:classⅠreservoirs adopted the"barite removal+acidification"process to remove barite pollution and blockage,dissolve calcium in fractures,and dredge natural fracture systems;classⅡandⅢreservoirs with varying degrees of natural fracture development adopted fracture network fracturing technology.The pre fluid reduced the reservoir temperature and activated the natural fracture system,and the main fracturing fluid carried sand to form a high conductivity main fracture network system.For reservoirs with large thickness that cannot achieve uniform vertical transformation through general transformation,a layered transformation process was adopted.For wells with interlayer stress differences of 2-5 MPa,the temporary plugging soft layering process was preferred,and the fracture network fracturing adopted a temporary plugging soft layering process with different particle size combinations of"powder+ceramist".For interlayer stress difference greater than 5 MPa,mechanical layering transformation process was adopted.If the span between two packers was greater than 60 m,mechanical layering+soft layering composite layering process was adopted.A basic fracturing fluid system mainly composed of super guar gum thickener was developed,with ceramic particles with a particle size of 40-70 mesh selected as the proppants.The supporting temporary plugging and turning materials mainly

关 键 词：深层致密砂岩气藏 增产改造 体积压裂 暂堵转向 

分 类 号：TE375[石油与天然气工程—油气田开发工程]