断块油藏注采耦合提高采收率机理及矿场实践  

Mechanism and field practice of enhanced oil recovery by injection-production coupling in fault block reservoirs

作　　者：刘仁静[1] 陆文明[2] LIU Renjing;LUWenming(Sinopec International Exploration and Production Corporation,Beijing 100029,China;Sinopec Petroleum Exploration and Production Research Institute,Beijing 102206,China)

机构地区：[1]中国石化国际石油勘探开发公司,北京100029 [2]中国石化石油勘探开发研究院,北京102206

出　　处：《岩性油气藏》2024年第3期180-188,共9页Lithologic Reservoirs

基　　金：国家科技重大专项“断块油田特高含水期提高水驱采收率技术”(编号:2016ZX05011-002)资助。

摘　　要：针对渤海湾盆地济阳坳陷东营凹陷古近系断块油藏水驱开发后期流线固定导致注入水无效循环的问题,基于渗流力学和油藏工程原理,通过室内物模模拟和油藏数值模拟,提出了“细分开发层系、轮注轮采”的注采耦合开发调整技术,并验证了该技术可提高采收率的原理。研究结果表明:(1)利用注采耦合开发技术建立的“注入期间的高渗通道与低渗通道吸水量比模型”和“采油期间主流线和非主流线产油量比模型”均揭示了“改变压力场促进渗流场调整,实现均匀注入和均匀采出,扩大水驱波及系数和增加驱油效率”的注采耦合渗流力学机制。(2)注采耦合技术可以实现“扩大波及系数、增加驱油效率”,起到类似“调剖”的作用,高含水期通过此项技术可将低渗透岩心的分流率由1.0%提到18.6%,模型驱替更均衡;经过2个轮次的注采耦合调整,高、低渗透岩心的原油采收率分别提高了10.3%和16.1%。(3)研究区D断块古近系沙河街组沙二段Es236含油小层油藏注采耦合开发数值模拟结果显示,主流线和非主流线驱替更均匀,两者压力梯度极差由2.3下降至1.4。经过3个轮次注采耦合开发调整,沙二段3—6砂层组油藏平均综合含水率下降了3.2%,累计增油1 760 t,提高原油采收率2.1%,增油降水效果显著。Aiming at the problem of ineffective circulation of injected water caused by fixed streamline in the late stage of water drive development of Paleogene fault block reservoirs in Dongying Sag,Jiyang Depression,Bohai Bay Basin,based on seepage mechanics and reservoir engineering principles,the injection-production coupling development adjustment technology of“subdividing development layers,rotating injection and production”was proposed by means of indoor physical model simulation and reservoir numerical simulation,and the mechanism of enhancing oil recovery by this technology was clarified.The results show that:(1)The water absorption ratio model between high permeability channel and low permeability channel during injection and the oil production ratio model of mainstream line and non-mainstream line during oil production established by the injection-production coupling development technology reveal the injection-production coupling seepage mechanics mechanism of“changing pressure field to promote the adjustment of seepage field,achieving balanced injection and production,expanding sweep efficiency of water drive and increasing the oil displacement efficiency”.(2)The injection-production coupling technology can achieve remarkable development effect of“expanding sweep efficiency and increasing oil displacement efficiency”,that is,it plays a similar role of“profile control”.During the high water cut period,this technology can increase the diversion rate of low permeability cores from 1.0%to 18.6%,and the model displacement is more balanced.After two rounds of injection-production coupling adjustment,the oil recovery of high and low permeability cores increased by 10.3%and 16.1%,respectively.(3)The numerical simulation results of injection-production coupling development of Es236 oil-bearing sublayer of Paleogene Shahejie Formation in fault block D of the study area show that the displacement of mainstream line and non-mainstream line was more balanced,and the pressure gradient range between them decr

关 键 词：注采耦合 物理模拟 数值模拟 极差 渗流场 水驱采收率 断块油藏 沙河街组 东营凹陷 渤海湾盆地 

分 类 号：TE312[石油与天然气工程—油气田开发工程] P618.13[天文地球—矿床学]