页岩油蓄能体积压裂开发效果预测与评价方法  

Prediction and evaluation method for development effect of shale oil storage volume fracturing

作　　者：许宁[1] 陈哲伟 许琬晨 王玲[1] 崔晓磊[1] 蒋美忠[1] 战常武[1] XU Ning;CHEN Zhewei;XU Wanchen;WANG Ling;CUI Xiaolei;JIANG Meizhong;ZHAN Changwu(Exploration and Development Research Institute,Liaohe Oilfield Company,PetroChina,Panjin,Liaoning 124010,China;PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China;Panjin Xinglongtai State Capital Investment Operation Co.,Ltd.,Panjin,Liaoning 124010,China)

机构地区：[1]中国石油辽河油田分公司勘探开发研究院,辽宁盘锦124010 [2]中国石油勘探开发研究院,北京100083 [3]盘锦市兴隆台区国有资本投资运营有限公司,辽宁盘锦124010

出　　处：《油气藏评价与开发》2024年第5期741-748,755,共9页Petroleum Reservoir Evaluation and Development

基　　金：中国石油科学研究与技术开发项目“低/超低渗透油田有效开发关键技术研究”(2021DJ1304)。

摘　　要：蓄能体积压裂(以下简称蓄压)是页岩油藏提前补充地层能量、大幅提升单井产量的主要开发方式,应用广泛。通过渗吸与驱替机理结合实际生产数据统计分析,提出了根据返排率预测蓄压开发阶段最大累计产油量方法。研究结果表明:返排率30%之后,蓄压的累计产油量与返排率对数呈强线性相关,可预测压后单井最大累计产油量;该方法已经得到其他页岩油藏实际生产数据的实证,较递减曲线分析法更加准确且更具普适性,是对储层条件、压裂规模与工艺、焖排采工作制度等主客观因素的综合评价。返排率法可进一步确定液油比和合理返排速度。蓄压排采的平均返排速度控制在6~8 m^(3)(/d·km),与渗吸排油速度相匹配,能够更加高效地利用蓄压补充的弹性能量,取得较高采收率和较低的液油比。单井压后最大可采油量的返排率预测法为蓄压的经济效益评价、生产制度优化、压裂成本控制等提供了依据,对地质-工程一体化、优化井网井距和压裂设计具有重要指导意义。Energy storage volume fracturing is a pivotal early development technique for shale reservoirs,designed to supplement reservoir energy preemptively and significantly boost single well production.A method for predicting the maximum cumulative oil production during the development stage of energy storage fracturing is proposed,based on the mechanisms of imbibition and displacement coupled with the statistical analysis of actual production data.The results demonstrate that following a 30%flowback ratio,the cumulative oil production from energy storage fracturing exhibits a strong linear relationship with the logarithm of the flowback ratio.This relationship can predict the maximum cumulative oil production of a single well after fracturing.Validated by actual production data from other shale reservoirs,this method proves to be more accurate and universal than the decline curve analysis method.It encompasses a comprehensive evaluation of subjective and objective factors such as reservoir conditions,fracturing scale and technology,production system design,and drainage efficiency.Additionally,the method facilitates the determination of the liquid-to-oil ratio and the reasonable flowback rate.By controlling the average rate of discharge and production within the range of 6~8 m^(3)(/d·km),which aligns with the rates of oil drainage and imbibition,higher oil recovery and a lower liquid-to-oil ratio are achieved.This prediction method for maximum recoverable oil post-single well fracturing provides a basis for the economic benefit evaluation,production system optimization,and fracturing cost control of energy storage fracturing.It holds significant guiding importance for geological-engineering integration,well spacing optimization,and fracturing design.

关 键 词：返排率 蓄能 压裂 采收率 累计产油量 

分 类 号：TE349[石油与天然气工程—油气田开发工程]