已开发低渗油藏CO_2与N_2驱实验研究  

Study on the Experiment of N_2 Booster CO_2 Flooding for Developed Low Permeability Oil Reservoirs

作　　者：范智慧[1] 邴绍献[2] 聂法健[3] 田巍[3] Fan Zhihui Bing Shaoxian Nie Fajian Tian Wei(Exploration ＆ Production Department ,SINOPEC ,Beijing 100728 Research Institute of Exploration and Development SINOPEC Shengli Oilfield Company,Dongying Shandong 257015 Research Institute of Petroleum Exploration ＆ Produetion,SINOPEC Zhongyuan Oilfield Company,Puyang Henan 457001)

机构地区：[1]中国石油化工股份有限公司油田勘探开发事业部,北京100728 [2]中国石化胜利油田分公司勘探开发研究院,山东东营257015 [3]中国石化中原油田石油勘探开发研究院,河南濮阳457001

出　　处：《中外能源》2017年第5期55-60,共6页Sino-Global Energy

基　　金：国家高技术研究发展计划(863)项目"二氧化碳提高石油采收率与封存关键技术研究"(编号:2009AA063406)资助

摘　　要：为深化研究已开发低渗油藏注气提高采收率机理,优化注气方式,通过采用长岩心物理模拟实验,考察油藏在目前地层压力条件下连续注CO_2驱、连续注N2驱、CO_2前段塞+N_2后续驱等不同注入方式下的气驱驱油效果。研究表明,N_2助推CO_2方式可有效提高原油采收率,实验产出关系曲线呈现"S"形态,分为3个阶段,采出程度的大幅增加主要发生在注气开发开采的第一阶段,对于衰竭开采后的注气实验,连续注CO_2驱、0.41HCPVCO_2前段塞+N_2后段塞的总采收率几乎相当,都超过了80%,因此采用N_2助推,如果CO_2段塞体积选择适当,其效果完全不逊于连续CO_2驱,而且降低了CO_2使用量,另N_2制备和运输整个流程中风险都较小,即使出现气体泄漏,也不会对环境造成太大伤害和影响,经济效益大幅提高。该研究成果将为低成本高效动用已开发低渗油藏提供技术支撑。In order to further study mechanism of EOR by gas injection and to optimize gas injection method for the developed low permeability oil reservoirs,the recovery of continuous CO2 flooding,continuous N2 flooding and N2 booster CO2flooding was respectively researched under the condition of current formation pressure through long core physical simulation experiment.The research shows that the N2 booster CO2flooding can effectively enhance oil recovery,and the experiment output curve presents S form and may be divided into three stages.Greatly improved recovery degree mainly occurred during the first stage of gas injection.But the total recovery is almost equal for the continuous CO2 flooding and 0.41HCPVCO2＋N2flooding,and they were all over 80% in the experiment of gas injection after depletion development.So,the way of N2 booster CO2flooding is implemented,and its effect of displacement will equal to that of the continuous CO2 flooding if CO2 injection size is reasonable.Economic benefit will be improved for less CO2 consumption,few risks in the process of N2 preparation and transportation and less damage on the environment even if gas leakage.This re-search results supply technology supports for efficient development of the developed low permeability oil reservoirs with low cost.

关 键 词：低渗油藏 N2助推CO2驱 采收率 高效动用 长岩心实验 

分 类 号：TE357.7[石油与天然气工程—油气田开发工程]