摘要
延长油田致密砂岩储层普遍存在井浅、能量低、天然裂缝发育及非均质性强等特性。为增大泄油面积,实施每口井压裂,但此举加剧了注水问题的凸显。转注CO_(2)代替注水时,面临气体窜逸问题,这导致驱油效果差,封存率大幅下降。在高矿化度、低温、低压的实际储层条件下,通过室内模拟手段,针对多尺度通道气窜问题,研发了一种具有多极差两级协同、强度差异特性的“防、治”一体化调驱体系。岩心实验结果表明,在低渗、酸性、高矿化度环境下,0.4%AOS+0.3%OP-40+0.4%HPAM与2 000 mg/L AP+0.05%有机铬+0.10%酚醛树脂交联剂组合的弱凝胶封窜体系和起泡体系,均展现出良好的起泡性、成胶性和黏弹性。当极差为10时,主要采用以防为主的泡沫防窜方式;极差为50时,则采用凝胶泡沫防治一体防窜方式,从而形成了适用于不同尺度的调驱与封窜一体化技术。该技术能够启动低渗储层达40%以上,并在CO_(2)驱油过程中提高封存率约80%,同时使储层压力提升可达3 MPa。该体系在现场实施后,实现了月增油70%以上的显著效果,伴生气CO_(2)气量下降了80%,地层压力提升了3~5 MPa,从而有效改善了CO_(2)驱油及封存效果。
Shallow wells,low energy,natural fractures and strong heterogeneity are the common characteristics of tight sandstone reservoirs in Yanchang Oilfield.In order to increase the drainage area,the problem of water injection is aggravated by fracturing of mouth wells.CO_(2) Injection by water injection is faced with runaway,which leads to poor oil displacement effect and great decrease in storage rate.Under the conditions of actual high salinity,low temperature and low pressure,a multi-pole and two-stage coordinated control and displacement system with different intensity is developed by means of indoor simulation.The core test results show that:under low permeability,acid and high salinity environment,the weak gel sealing and foaming system of 0.4%AOS+0.3%OP-40+0.4%HPAM and 2000 mg/L AP+0.05%organic chromium+0.10%phenolic resin crosslinking agent has good gel-forming foamability,property and viscoelasticity.When the range is 10,the foam anti-channeling method based on prevention is used,and when the range is 50,the gel foam prevention and integrated anti-channeling method is used to form an integrated technology of different scale regulation and channeling,which can start the low-permeability reservoir up to 40%,improve the storage rate of about 80%in the process of CO_(2) flooding,and increase the reservoir pressure up to 3 MPa.After the on-site implementation of the system,the monthly oil increase is more than 70%,the associated gas CO_(2) gas volume is reduced by 80%,and the formation pressure is increased by 3~5 MPa,which effectively improves the effect of CO_(2) flooding and storage.
作者
赵聪
陈龙龙
汤瑞佳
江绍静
郑玉兰
肖沛瑶
高泽
刘楠
ZHAO Cong;CHEN Longlong;TANG Ruijia;JIANG Shaojing;ZHENG Yulan;XIAO Peiyao;GAO Ze;LIU Nan(Research Institute of Yanchang Petroleum(Group)Co.,Ltd.,Xi’an 710065,China;Xingzichuan Oil Production Plant of Yanchang Oilfield Co.,Ltd.,Yan’an 717400,China;Nature Gas Research Institute of Yanchang Petroleum(Group)Co.,Ltd.,Xi’an 710065,China)
出处
《应用化工》
北大核心
2025年第11期2986-2992,共7页
Applied Chemical Industry
基金
陕西省秦创原“科学家+工程师”项目(2022KXJ-050)
陕西省重点研发计划(2023-YBGY-311)
延长石油集团“揭榜挂帅”项目(ycsy2021jbgs-A-04-01)。
关键词
致密砂岩油藏
多尺度气窜防治一体化
CO_(2)驱油与封存
低温高矿化度
现场实施
tight sandstone reservoir
multi-scale gas channeling control integration
CO_(2)flooding and storage
low temperature and high salinity
field implementation
