摘要
裂缝型潜山油藏储集层非均质性强,油藏开发过程中驱替流体指进和窜流频发,封堵裂缝、大孔道等高渗流通道是提高原油采收率的有效措施。通过岩心流动实验,评价了微球对B1潜山油藏储集层岩心裂缝及大孔道的封堵效果,探究了采用微球-天然气驱提高剩余油动用的有效性。结果表明,单一水驱或天然气驱的驱油效率不显著,采用微球驱,微球进入岩心后的膨胀和封堵作用使得阻力系数、注入压力等显著增大;微球粒径直接影响封堵性能,若粒径太小,达不到封堵的效果,若粒径太大,不易注入;微球注入岩心后的膨胀、封堵、解堵、变形后再封堵及天然气溶解的协同作用,对裂缝型潜山油藏开发过程中的驱替流体指进及窜流有明显抑制作用,微球-天然气驱可大幅提高剩余油采出程度。
During the development of fractured buried-hill reservoirs which are highly heterogeneous,fingering and channeling occur frequently;therefore,blocking high permeability channels such as fractures and large pores is an effective measure to improve oil recovery of these reservoirs.Through laboratory experiments on flowing in the cores from the B1 buried-hill reservoir,the plugging effect of microspheres on both fractures and large pores in the cores was evaluated,and the effectiveness of microsphere-natural gas flooding to improve the recovery of remaining oil was discussed.The results show that the oil displacement efficiency of water flooding or natural gas flooding is inapparent.When microsphere flooding is adopted,the microspheres significantly increase the resistance coefficient and injection pressure due to their expansion and plugging after entering the core.The microsphere size directly affects the plugging effect.If the microsphere size is too small,good plugging effect cannot be achieved;if the microsphere size is too large,microsphere injection is difficult.The expansion,plugging,unplugging,deformation plugging of the injected microspheres and the dissolution of the injected natural gas are synergic to effectively inhibit the fingering and channeling of displacing fluid during the development of fractured buried-hill reservoirs.Therefore,microsphere-natural gas flooding can greatly improve the recovery degree of remaining oil.
作者
陈世杰
孙雷
潘毅
王亚娟
林友建
陈汾君
CHEN Shijie;SUN Lei;PAN Yi;WANG Yajuan;LIN Youjian;CHEN Fenjun(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China;No.4 Gas Production Plant,Southwest Oil and Gas Company,Sinopec,Chongqing 402160,China;Research Institute of Exploration and Development,Qinghai Oilfield Company,PetroChina,Dunhuang,Gansu 736202,China)
出处
《新疆石油地质》
CAS
CSCD
北大核心
2022年第4期468-473,共6页
Xinjiang Petroleum Geology
基金
中国石油科技重大专项(2017E-1603)。
关键词
潜山油藏
微球
天然气驱
驱油效率
变形封堵
注入体积
buried-hill reservoir
microsphere
natural gas flooding
oil displacement efficiency
deformation plugging
injection volume