高含水复杂断块油藏单层系边外注水开发模式
Single-layer outer edge waterflooding development model of complex fault block reservoirs with high water cut
姚秀田 1徐磊 2王冉冉 2闫森 2王明鹏 2杨琴文2
作者信息
- 1. 中国石化胜利油田分公司 孤岛采油厂,山东 东营 257231;中国地质大学(北京)能源学院,北京 100083
- 2. 中国石化胜利油田分公司 孤岛采油厂,山东 东营 257231
- 折叠
摘要
复杂断块油藏在开发后期面临综合含水率高、地层能量不足、剩余油分布复杂、井网适应性差等问题.以济阳坳陷沾化凹陷中部垦71断块油藏为例,基于水驱油藏的油包水和水包油2种油水分布状态,利用理论模型推导和数值模拟方法,开展了单层系边外注水开发模式研究.结果表明:从采液端和注水端的受力分析可获得单层系开发的合理注水量、合理采液量和合理注采井距,单层系开发的合理注水压差、合理注水量、合理采液量是影响其剩余油饱和度、含水饱和度的关键因素,对油层合理地层压力水平及剩余油二次富集起主要控制作用.通过加大注采井距至油水边界外围,以2.9倍含油条带宽度为合理注采井距的临界值,采用短注长静置的非对称周期注采方式,建立单层系边外注水开发模式,有利于保持单层系的压力系统稳定和提高剩余油波及率,从而提高原油采收率.矿场实践表明,采用单层系边外注水开发模式后,垦71断块油藏日产油量提高至254 t/d,含水率控制在93.7%,采收率提高至31.53%,采油速率提高4.9%,显示出良好的增产效果.单层系边外注水开发模式解决了高含水复杂断块油藏开发中的剩余油分布分散、水驱波及率低和井网适应性差等难题,可为复杂断块油藏开发提供指导和借鉴.
Abstract
In the late stage of development,the complex fault block reservoir faces a series of problems,such as high comprehen-sive water cut,lack of formation energy,complex remaining oil distribution,and poor well pattern suitability.In this paper,based on the oil-water distribution status of the waterflooding reservoir,such as water-in-oil and oil-in-water,the development mode of single-layer outer edge waterflooding was studied through theoretical model derivation and numerical simulation methods by taking Ken71 fault block reservoir in the middle of Zhanhua Sag of Jiyang Depression as an example.The results show that the reasonable water injection volume,fluid production volume,and spacing between injection and production wells during single-layer develop-ment can be obtained through the force analysis of the fluid production end and the water injection end.The key factors affecting the remaining oil saturation and the water saturation are reasonable water injection pressure difference,water injection volume,and fluid production volume of single-layer development systems.It is essential in controlling the reasonable formation pressure level and the secondary enrichment of the remaining oil.The spacing between injection and production wells increases to the periphery of the oil-water boundary,and 2.9 times the width of the oil-bearing strip is the critical value of reasonable spacing between injection and production wells.An asymmetric periodic injection and production method with short injection and long standing is adopted to establish a single-layer outer edge waterflooding development model,which is beneficial to maintain the stability of the pressure system and increase the sweep efficiency of the remaining oil of the single-layer,so as to improve the oil recovery.Field application shows that after applying the single-layer outer edge waterflooding development model,the daily production of Ken71 fault block increases to 254 t,the water cut is controlled to 93.7%,the recovery increases to 31.53%,and the oil recovery rate is increased by 4.9%,which shows an excellent yield-increasing effect.The single-layer outer edge waterflooding model solves the problems in the development of complex fault block reservoirs with high water cut,such as dispersed remaining oil distribution,low waterflooding sweep efficiency,and poor well pattern suitability and can provide guidance and reference for complex fault block reservoir devel-opment.
关键词
单层系边外注水/开发模式/周期注水/数值模拟/复杂断块油藏Key words
single-layer outer edge waterflooding/development model/periodic waterflooding/numerical simulation/complex fault block reservoir引用本文复制引用
基金项目
国家科技重大专项(2017ZX05049-004)
出版年
2024
国家科技期刊平台
NSTL
万方数据