摘要
针对鄂尔多斯盆地页岩油储层压力低、缝网复杂程度低和黄土塬水资源缺乏等问题,以该盆地庆城油田页岩油为研究对象,进行了滑溜水和CO_(2)压裂物理模拟试验,利用高能CT监测了CO_(2)压裂裂缝扩展规律,分析了CO_(2)压裂形成复杂裂缝的可行性;利用油藏数值模拟方法,优化了CO_(2)注入关键参数,形成了适合庆城油田页岩油的CO_(2)区域增能体积压裂技术。研究表明:前置CO_(2)压裂可提高长7段页岩油储层裂缝复杂程度,裂缝沿层理弱面扩展并纵向穿层形成缝网;增能理念应由单井段间交替增能向平台整体注入实现井间、段间协同一体增能转变,单井采用全井段注入增能模式,可实现缝控区域全覆盖。庆城油田某平台进行了页岩油CO_(2)区域增能体积压裂试验,与采用常规体积压裂技术的邻井相比,3口试验水平井平均压力保持程度提高1.5倍,单井平均初期产油量提高28.6%。研究和现场试验结果表明,CO_(2)区域增能体积压裂能提高裂缝复杂程度,增加区域地层能量,提高单井产能,可为鄂尔多斯盆地页岩油开发提供技术支持。
In response to the problems of low pressure,high fluid flow resistance,low energy enhancement efficiency of slick water fracturing,and low complexity of fracture networks in shale oil reservoirs in Ordos Basin,a physical simulation experiment of slick water and CO_(2) fracturing was conducted in the Qingcheng shale oil block of Ordos Basin.The expansion law of CO_(2) fracturing fractures was monitored using high-energy computerized tomography(CT)scanning,and the feasibility of CO_(2) fracturing to form complex fractures was analyzed.By using reservoir numerical simulation methods,the key parameters of CO_(2) injection were optimized,forming a CO_(2) regional energy enhancement and volumetric fracturing technology suitable for the Qingcheng shale oil block.Research showed that pre-CO_(2) fracturing could increase the complexity of fractures in Chang 7 shale oil,with fractures spreading along weak bedding planes and forming a fracture network through the layers vertically.The concept of energy enhancement should be achieved by injecting energy into the platform as a whole instead of alternating energy enhancement between single well sections and injecting energy into the platform as a whole,achieving a transformation of integrated energy enhancement between wells and sections.The single well that adopted the full well section injection energy enhancement mode could achieve full coverage of the fracture control area.Based on a platform in the Qingcheng shale oil block,a shale oil CO_(2) regional energy enhancement and volumetric fracturing test was conducted.Compared with conventional volumetric fracturing adjacent wells,the average pressure retention of the three test horizontal wells increased by 1.5 times,and the average initial oil production of a single well increased by 28.6%.Research and on-site experiments showed that CO_(2) regional energy enhancement and volumetric fracturing could increase the complexity of fractures,enhance regional formation energy,and improve single well productivity,providing technical support for shale oil development in Ordos Basin.
作者
张矿生
齐银
薛小佳
陶亮
陈文斌
武安安
ZHANG Kuangsheng;QI Yin;XUE Xiaojia;TAO Liang;CHEN Wenbin;WU An’an(PetroChina Changqing Oilfield Company,Xi’an,Shaanxi,710018,China;Oil and Gas Technology Research Institute,PetroChina Changqing Oilfield Company,Xi’an,Shaanxi,710018,China)
出处
《石油钻探技术》
CAS
CSCD
北大核心
2023年第5期15-22,共8页
Petroleum Drilling Techniques
基金
国家科技重大专项“鄂尔多斯盆地致密油开发示范工程”(编号:2017ZX05069)
中国石油天然气股份有限公司重大专项“鄂尔多斯盆地页岩油勘探开发理论与关键技术研究”(编号:2021DJ1806)联合资助。
关键词
页岩油
水平井
CO_(2)区域增能
体积压裂
物理模拟
数值模拟
鄂尔多斯盆地
shale oil
horizontal well
CO_(2) regional energy enhancement
volumetric fracturing
physical simulation
numerical simulation
Ordos Basin
