延长油田致密油藏注水吞吐机理及应用  

Mechanism of Cyclic Water Injection and Its Application in Tight Oil Reservoirs in Yanchang Oilfield

作　　者：高涛 赵习森 党海龙 张志升 吴向阳 Gao Tao;Zhao Xisen;Dang Hailong;Zhang Zhisheng;Wu Xiangyang(Shaanxi Yanchang Petroleum(Group)Co.,Ltd.,Xi’an,Shaanxi 710075,China;Yanchang Oilfield Company Limited,Yan’an,Shaanxi 717400,China)

机构地区：[1]陕西延长石油(集团)有限责任公司,陕西西安710075 [2]延长油田股份有限责任公司,陕西延安717400

出　　处：《特种油气藏》2018年第4期134-137,共4页Special Oil & Gas Reservoirs

基　　金：国家"973"计划"致密油高效开发油藏工程理论与方法研究"(2015CB250905);陕西省科技统筹创新项目"延长难采储量有效动用开发技术研究"(2016KTCL01-12)

摘　　要：为探索致密油藏采收率提高方法,解决该类油藏能量补充困难问题,以延长油田南部地区长_8储层为研究对象,开展长岩心室内吞吐实验,结合核磁共振测试,分析了注水吞吐作用机理及主控因素。结果表明:相同开发条件下,回采速度越低采出程度越高,憋压时间和压力存在最佳值,吞吐周期建议开展3次;渗吸作用是注水吞吐的主要机理,致密岩心自发渗吸驱油效率平均为15.61%。以王平X井为例,初期日产油为14.6 t/d,衰竭开采12个月日产油降为3.9 t/d,注水1 630 m^3,闷井15 d后开井,日产油为13.3 t/d。注水吞吐技术在致密油藏能量补充、提高单井产量方面效果显著。该项研究为类似油藏注水吞吐开发提供了借鉴。In this paper,Chang 8 reservoir in the south of Yanchang Oilfield was taken as the study object to explore the EOR methods of tight oil reservoirs and deal with the energy supplement difficulties of tight oil reservoirs.Indoor long-core huff and puff experiments were carried out.Then,based on nuclear magnetic resonance(NMR)test,the mechanisms and main control factors of cyclic water injection were analyzed.It is shown that in the same development conditions,the degree of reserve recovery increases with the decrease of stopping rate and there are optimal pressure build-up time and pressure.It is recommended to carry out three cycles of huff and puff.It is indicated that imbibition is the primary mechanism of cyclic water injection and the oil displacement efficiency of tight core contributed by autogenic imbibition averages 15.61%.In Well Wangping X,for example,its oil production rate is 14.6 t/d in the early stage and then declines to 3.9 t/d after 12 months’depletion development.Then,1 630 m 3 water is injected,and after 15 days’well killing,its oil production rate is 13.3 t/d.In conclusion,cyclic water injection plays a remarkable role in improving energy supplement of tight oil reservoirs and single well production.The research provides the reference for the cyclic water injection development of similar oil reservoirs.

关 键 词：注水吞吐 渗吸作用 长岩心驱替 核磁共振 致密油藏 延长油田 

分 类 号：TE357.6[石油与天然气工程—油气田开发工程]