基于现场试井数据和岩心驱替试验的采油初期渗透率演化规律  

Permeability evolution in the initial period of oil production based on field well test data and coreflooding tests

作　　者：KOZHEVNIKOV V.Evgenii TURBAKOV S.Mikhail RIABOKON P.Evgenii GLADKIKH A.Evgeniy POPLYGIN V.Vladimir GUZEV A.Mikhail 戚承志 KOZHEVNIKOV V.Evgenii;TURBAKOV S.Mikhail;RIABOKON P.Evgenii;GLADKIKH A.Evgeniy;POPLYGIN V.Vladimir;GUZEV A.Mikhail;QI Cheng-zhi(Department of Oil and Gas Technologies,Perm National Research Polytechnic University,Perm 614990,Russia;Institute of Applied Mathematics,Far Eastern Branch of the Russian Academy of Sciences,Vladivostok 690041,Russia;Civil and Transportation School,Beijing University of Civil Engineering and Architecture,Beijing 100044,China)

机构地区：[1]彼尔姆国立科研理工大学石油和天然气技术系,俄罗斯彼尔姆614990 [2]俄罗斯科学院远东分院应用数学研究所,俄罗斯符拉迪沃斯托克690041 [3]北京建筑大学土木与交通工程学院,中国北京100044

出　　处：《岩土力学》2023年第3期834-842,共9页Rock and Soil Mechanics

基　　金：俄罗斯科学基金(No.19-79-10034)。

摘　　要：油气开采过程中渗透率预测是一个非常重要的问题。由于油气储量衰竭导致渗透率降低,储层压力下降(有效压力增加),导致油气生产时间增加。对有效压力导致渗透率降低的问题进行了大量研究,主要是通过各种方法建立渗透率模型,如岩心驱替试验和现场试井。前期研究结果表明,渗透率对有效压力具有幂律或指数依赖性,然而,预测渗透率的困难在于滞后现象,其原因尚不完全清楚。一些学者利用储层力学模型模拟渗透率以及解释滞后的原因,但该模型在油气生产初期有效压力波动较小时并不适用。在这项工作中,分析Perm地区北部一个油田的试井数据得出:生产初期的储层渗透率很大程度上取决于流体产出量。基于陆相储层的试井数据,得到一个描述采油初期渗透率变化的模型。为验证该模型,根据专门开发的程序对陆相储层样品进行岩心驱替试验。岩心驱替结果表明,从试井数据中获得的模型具有高收敛性。利用计算机断层扫描(computed tomography,简称CT)和扫描电镜(scanning electron microscope,简称SEM)研究岩心孔隙的属性和结构,发现天然胶体的迁移是生产初期低黏土岩石渗透率下降的主要原因。Permeability prediction during hydrocarbon production is a rather important problem.The decrease in permeability due to depletion reserves and the drop in reservoir pressure(increase in effective pressure)leads to an increase in the time of oil or gas production.A large number of works have been devoted to the problem of permeability reduction due to effective pressure.Establishment of permeability models is carried out by various methods including coreflooding tests and field well tests.The results of previous studies have shown that permeability has a power-law or exponential dependence on effective pressure,however,the difficulty in predicting permeability is due to hysteresis,the causes of which remain not fully understood.To model permeability,as well as explain the causes of hysteresis,some authors use mechanical models of the reservoir,which cannot be applied with small fluctuations in effective pressures in the initial period of hydrocarbon production.In this work,we analyzed data from well tests at one of the fields in the north of the Perm region and came to the conclusion that in the initial period of production,the permeability of the reservoirs largely depends on the amount of fluid produced.Based on the well test data of the terrigenous reservoir,a model was obtained that describes the change in permeability in the initial period of oil production.To confirm the model,coreflooding tests of samples of the terrigenous reservoir were carried out according to a specially developed program.Coreflooding results showed high convergence of the model obtained from well test data.With computed tomography(CT)and scanning electron microscope(SEM),the properties and structure of the pore space of the cores were studied and it was found that the main reason for the decrease in the permeability of low-clay rocks in the initial period of production is the migration of natural colloids.

关 键 词：渗透率 渗透率滞后 胶体迁移 岩心驱替 多孔介质 

分 类 号：TU451[建筑科学—岩土工程]