致密油储层气驱油核磁共振实验研究  

NMR experimental study of gas flooding of tight oil reservoir

作　　者：戴仪心 郭和坤 李海波[1,3] 杨正明 孟立新[4] 张亚蒲 曾庆桥[5] 孟焕[1] DAI Yixin;GUO Hekun;LI Haibo;YANG Zhengming;MENG Lixin;ZHANG Yapu;ZENG Qingqiao;MENG Huan(Institute of Porous Flow and Fluid Mechanics, PetroChina Research Institute of Petroleum Exploration & Development, Langfang, Hebei 065007, China;School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China;Institute of Porous Flow and Fluid Mechanics, University of Chinese Academy of Sciences, Langfang, Hebei 065007, China;Dagang Oilfield Exploration and Development Research Institute, Tianjin 300280, China;North China Oilfield Exploration and Development Research Institute, Renqiu,Hebei 062552, China)

机构地区：[1]中国石油勘探开发研究院渗流流体力学研究所,河北廊坊065007 [2]中国科学院大学工程科学学院,北京100049 [3]中国科学院渗流流体力学研究所,河北廊坊065007 [4]大港油田勘探开发研究院,天津300280 [5]华北油田勘探开发研究院,河北任丘062552

出　　处：《中国科技论文》2020年第1期105-111,共7页China Sciencepaper

摘　　要：针对鄂尔多斯盆地致密油储层岩心,将核磁共振(nuclear magnetic resonance,NMR)技术与气驱油物模实验相结合,对储层原油赋存特征和气驱油后微观剩余油分布特征进行研究。研究表明:气驱油前目标储层总含油率较高,但微米孔隙(>1μm)赋存油量较少(7.27%),原油主要赋存于亚微米(0.1~1μm,包括0.1μm及1μm)和纳米孔隙(<0.1μm)中(分别为27.67%和24.00%);气驱油1 PV(pore volume)后,微米孔隙原油相对采出程度R较高(64.34%),亚微米孔隙次之(37.27%),纳米孔隙较低,气驱早期首先将赋存于较大孔隙内的原油驱出,较小孔隙内原油动用程度较低;气驱油50 PV后,储层微米孔隙几乎无剩余油,R达到90%以上,亚微米孔隙有一定量剩余油,R约为60%,纳米孔隙R较低,是剩余油主要赋存空间;随渗透率的降低,储层较大孔喉比例减少,微观非均质性降低,气驱油微观波及程度增加,亚微米孔隙采出油量有增加的趋势;致密油储层注气能力明显优于注水能力,且渗透率越低,注气能力优势越明显。研究成果可为致密油有效开发及制定合理开发方式提供依据。This study aim at tight oil reservoir cores of Erdos basin,combining nuclear magnetic resonance(NMR)technology and core displacement test,and analysis microscopic oil distribution characteristics both initial state and after gas flooding of reservoir.Research show that:before gas flooding,the total oil percentage of target reservoirs is higher,but less oil(7.27%)exist in micron pores(greater than 1μm),oil mainly exist in the submicron pores(0.1~1μm,including 0.1μm and 1μm)and nanometer pores(less than 0.1μm),which about 27.67%and 24.00%respectively.After 1 PV gas flooding,reservoir recovery percent of reserves R of micron pores are higher(64.34%),submicron pores are second(37.27%),nanometer pores are lower.In early stage of gas flooding,oil in the larger pores are removed first,and oil production in smaller pores are lower.After 50 PV gas flooding,there are almost no residual oil in micron pores,R reaches over 90%,remaining oil of submicron pores have a certain amount,R about 60%,and R of nanometer pores are low,nanometer pores are the main storage space of residual oil.With the decrease of permeability,ratio of larger throat-pore in reservoir decreases,the microscopic heterogeneity decreases,lead to degree of gas flooding micro sweep increases,and the submicron oil recovery has an increasing trend.The gas injection capacity of tight reservoir is obviously better than that of water injection,and the lower the permeability reservoir have,the more obvious gas injection capacity get.The results provide theoretical basis for effective development and establishing rational development mode of tight oil reservoir.

关 键 词：致密油储层 气驱油 核磁共振 剩余油分布 非均质性 注气能力 鄂尔多斯盆地 

分 类 号：TE341[石油与天然气工程—油气田开发工程]