砂岩油田聚合物驱后油层微观剩余油分布规律  

Distribution law of microscopic remaining oil in polymer-flooded reservoirs of sandstone oilfield

作　　者：白振强[1] 王清华[1] 李亚[1] BAI Zhenqiang;WANG Qinghua;LI Ya(Exploration and Development Research Institute of Daqing Oilfield Co Ltd, Daqing163712, China)

机构地区：[1]大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712

出　　处：《大庆石油地质与开发》2021年第4期101-106,共6页Petroleum Geology & Oilfield Development in Daqing

基　　金：中国石油天然气股份有限公司重大科技专项“大庆油气持续有效发展关键技术研究与应用”(2016E-0207)。

摘　　要：针对大庆油田聚合物驱后油层微观剩余油分布规律,利用冷冻制片、紫外荧光和CT无损分析新方法,定量化确定了束缚态、半束缚态和自由态三大类的10种类型微观剩余油的空间分布特征。分析认为水驱、聚驱或三元复合驱后主要微观剩余油类型均以孔表薄膜状、颗粒吸附状和粒间吸附状为主,聚驱后剩余油比例分别减少了83.5%、49.4%和44.0%。三元复合驱后,在高浓度聚合物驱的基础上孔表薄膜状和颗粒吸附状微观剩余油又分别下降8.8%和27.8%。聚驱后分流线部位微观剩余油赋存状态以束缚态的颗粒吸附状和孔表薄膜状以及自由态的簇状和粒间吸附状为主。孔隙结构、乳化现象、贾敏效应、黏土矿物、颗粒表面吸附力、毛管力和微观非均质性引起的指进现象是产生微观剩余油的7种主要原因。研究成果为后续水驱开发和各种化学驱后剩余油的进一步挖潜提供了科学依据。According to the distribution law of microscopic remaining oil in polymer-flooded reservoirs of Daqing Oilfield,the spatial distribution characteristics are quantitatively determined by means of new methods such as frozen sectioning,UV fluorescence and CT nondestructive analysis for ten types of microscopic remaining oil in three major types,namely,bound state,semi bound state and free state.The analyses show that after flooded by water,polymer or ASP,the main types of microscopic remaining oil are principally pore surface film,particle adsorption and intergranular adsorption,and the proportions of remaining oil after polymer flooding are decreased by 83.5%,49.4%and 44%respectively.After ASP flooding,on the basis of high-concentration polymer flooding,the pore surface film and particle adsorption of micro-remaining oil are reduced by 8.8%and 27.8%iespectively.After polymer flooding,the micro-residual oil at fluid diversion line is mainly in form of bound-stateparticle adsorption and pore surface film as well as free-state cluster and intergranular adsorption.The seven fingering phenomena caused by pore structure,emulsification,Jiamin effect,clay minerals,particle-surface adsorption force,capillary force and micro heterogeneity are the main causes for microscopic remaining oil.It provides scientific evidences for further remaining-oil potential tapping for the subsequent water-flooding development and various chemical flooding.

关 键 词：紫外荧光 CT无损检测 微观剩余油 聚合物驱 复合驱 

分 类 号：TE343[石油与天然气工程—油气田开发工程]