裂缝性油藏渗流特征及注水策略
Seepage Characteristics and Water Injection Strategy of Fractured Reservoir
房娜 1刘宗宾 1岳宝林 1王双龙 1高岳1
作者信息
- 1. 中海石油(中国)有限公司天津分公司,天津 300452
- 折叠
摘要
为提高裂缝性油藏数值模拟精度,提供有效注水策略,以渤海大型裂缝性油藏锦州 25-1南潜山油藏为研究对象,采用数字岩心技术,结合多相流模拟,明确半风化壳上段和下段微观孔喉特征及相渗曲线特征,结合数值模拟和矿场实践,开展采油速度化及注水方式优化研究.研究表明:微裂缝发育程度对基质岩块相渗曲线和毛细管力曲线形态具有重要的控制作用;微裂缝越发育的岩心,驱油效率越高,越有利于产生基质渗吸作用;微裂缝长度和裂缝频数满足幂律分布规律,其幂律指数约为 1.5;开发初期裂缝系统的产量占主导地位,开发中后期基质系统的产量贡献逐步增加,裂缝系统和基质系统累计产量贡献比约为 2∶1;开发初期通过优化采油速度,含水上升阶段采用循环注水的方式,采收率预计提高 4.5 个百分点.该研究对于裂缝性油藏开发策略及注水方案的制订具有重要指导意义.
Abstract
A research for the optimization of oil recovery rate and water injection method was conducted with numeri-cal simulation and field practice so as to improve the accuracy of numerical simulation of fractured reservoirs and provide effective water injection strategies.In the study,a buried hill reservoir in JZ25-1S oilfield in the Bohai Bay Basin,a large fractured reservoir,is taken as a study object.With the use of digital core technology and multi-phase flow simulation,the characteristics of micropores and throats in the upper and lower semi-weathered crust and the characteristics of relative permeability curve are defined.The results indicate that development degree of microfractures plays an important role in controlling the shapes of relative permeability curve and the capillary curve of matrix block;the more developed the microfractures in the core,the higher the oil displacement efficiency,and the more conducive to matrix imbibition;the length and frequency of microfractures follow a power-law distribu-tion,with a power-law index of approximately 1.5;in the initial stage of development,the production are mainly from the fracture system,while in the middle and later stages of development,the production from the matrix system gradually increases;the cumulative production contribution ratio of the fracture system to the matrix system is ap-proximately 2∶1;the recovery rate is expected up by 4.5 percentage points through the optimization of the oil re-covery rate in the initial stage and utilization of cyclic water injection during the water-cut rising stage.This study provides important guidance for development strategies and water injection schemes for fractured reservoirs.
关键词
裂缝性油藏/微裂缝/相渗曲线/毛细管力曲线/采油速度/循环注水/数字岩心Key words
fractured reservoirs/micro-fractures/relative permeability curve/capillary force curve/oil recovery rate/cyclic water injection/digital core引用本文复制引用
基金项目
中海石油(中国)有限公司科技攻关项目(YXKY-2018-TJ-04)
出版年
2024
国家科技期刊平台
NSTL
万方数据