压裂液渗吸与富气页岩气井典型生产规律关系剖析  

Analysis of the Relationship Between Fracturing Fluid Imbibition and Typical Production Rules of Gas-rich Shale Gas Wells

作　　者：王科 卢双舫[2] 娄毅 李楠[4] 李海涛[5] 叶铠睿 张砚[7] 李松雷 Wang Ke;Lu Shuangfang;Lou Yi;Li Nan;Li Haitao;Ye Kairui;Zhang Yan;Li Songlei(College of Resources and Environmental Engineering,Guizhou University,Guiyang,Guizhou 550025,China;NEPU Sanya Offshore Oil&Gas Research Institute,Sanya,Hainan,572024,China;Guizhou Panjiang Coalbed Methane Development and Utilization Company Limited,Guiyang,Guizhou 550081,China;PetroChina Xinjiang Oilfield Company,Karamay,Xinjiang 834000,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China;CNPC Chuanqing Drilling Engineering Company Limited,Chengdu,Sichuan 610051,China;PetroChina Southwest Oil&Gas Field Company,Chengdu,Sichuan 610051,China;CNPC Bohai Drilling Engineering Company Limited,Tianjin 300450,China)

机构地区：[1]贵州大学资源与环境工程学院,贵州贵阳550025 [2]东北石油大学三亚海洋油气研究院,海南三亚572024 [3]贵州盘江煤层气开发利用有限责任公司,贵州贵阳550081 [4]中国石油新疆油田分公司,新疆克拉玛依834000 [5]西南石油大学油气藏地质及开发工程全国重点实验室,四川成都610500 [6]中国石油集团川庆钻探工程有限公司,四川成都610051 [7]中国石油西南油气田分公司,四川成都610051 [8]中国石油渤海钻探工程有限公司,天津300450

出　　处：《特种油气藏》2024年第3期158-166,共9页Special Oil & Gas Reservoirs

基　　金：贵州省科技重大专项“贵州省煤层气(煤矿瓦斯)抽采提产增效关键技术及工程试验”(黔科合战略找矿[2022]ZD001);贵州省科技计划“页岩气井预注CO_(2)增压防井间压窜机理研究”(黔科合基础-ZK[2022]一般106)。

摘　　要：压裂液渗吸会改变储层内的原始气水赋存特征,进而影响页岩气井生产规律。为此,通过动态驱替与核磁共振实验,结合前人研究成果,剖析了孔隙内原始气水分布、压裂液渗吸对通孔和盲孔内气体赋存的影响以及气井生产规律与压裂液渗吸的关系。研究表明:孔隙内原始气水赋存类型与矿物种类、裂缝孔径及储层湿度有关,小孔隙、孔角处存在束缚水,大孔隙内甲烷吸附面积随储层湿度的增大而减小,吸附气含量受有机质孔隙占比及成熟度的影响;近裂缝区存在渗吸影响区,在影响区内压裂液渗吸可促进吸附气解吸,并驱替非均衡渗吸通孔中的游离气,压缩均衡渗吸通孔及盲孔中的游离气;非均衡渗吸通孔中被驱替出的气体是水力裂缝中游离气的主要来源之一,只有当井筒、裂缝及影响区内滞留的压裂液排出,各区域内部的气体才能产出,从而导致产气曲线滞后于产水曲线的现象,且裂缝排液阻力远小于基质孔隙排液阻力,是产气及产水曲线呈“L”形递减的主要因素。该研究成果聚焦于压裂液渗吸对气体赋存及产出的影响,可丰富页岩气储层保护理论,对气井高效开发具有指导作用。The imbibition of fracturing fluid can alter the original gas-water occurrence in reservoirs,thereby affecting the production behavior of shale gas wells.However,through dynamic displacement and nuclear magnetic resonance experiments,combined with previous research results,we analysis of the original gas-water distribution in pores,the effects of fracturing fluid imbibition on gas occurrence in through-pores and blind-pores,and the relationship between gas well production behavior and fracturing fluid imbibition were carried out.The study reveals that the occurrence of original gas and water in pores is related to mineral types,fracture apertures,and reservoir humidity.There is bound water in small pores and pore corners.The adsorption area of methane in large pores decreases with increasing reservoir humidity,and the amount of adsorbed gas is influenced by the proportion of organic matter pores and maturity.A zone affected by imbibition exists near fractures,where fracturing fluid imbibition can promote desorption of adsorbed gas,displace free gas in non-equilibrium imbibition through-pores,and compress free gas in equilibrium imbibition through-pores and blind-pores.The gas displaced from non-equilibrium imbibition through-pores is one of the main sources of free gas in hydraulic fractures.Only when the fracturing fluid retained in the wellbore,fracture and influence area is discharged,was gas be produced from various areas,resulting in the phenomenon that the gas production curve lags behind the water production curve,and the fracture drainage resistance is much smaller than that of the matrix pore,which is the main reason for the"L"type decline of gas production and water production curve.The research findings focus on the impact of fracturing fluid imbibition on the occurrence and production of gas,contributing to the enrichment of shale gas reservoir protection theories.This has guiding significance for the efficient development of gas wells.

关 键 词：页岩气 压裂液渗吸 孔隙 气水赋存 吸附 

分 类 号：TE375[石油与天然气工程—油气田开发工程]