裂缝性油藏二氧化碳驱的多组分数值计算模型  

Model Formulation for Compositional Numerical Simulation of CO_2 Flooding in Fractured Reservoirs

作　　者：邸元[1] 吴玉树 鞠斌山[3] 

机构地区：[1]北京大学工学院,北京海淀100871 [2]美国科罗拉多矿业大学石油工程系,科罗拉多高登80401 [3]中国地质大学(北京)能源学院,北京海淀100083

出　　处：《西南石油大学学报（自然科学版）》2015年第2期93-100,共8页Journal of Southwest Petroleum University(Science & Technology Edition)

基　　金：国家科技重大专项(2011ZX05014);973计划(2011CB201004);国家自然科学基金(10932001)

摘　　要：对于预测油藏二氧化碳驱的效果,黑油模型不再适用,必须采用组分模型。研究了裂缝性油藏二氧化碳驱的三相多组分数值计算模型,给出了相关的计算方法和公式。采用多重连续介质理论来模拟裂缝性油藏中的输运过程,每个组分的质量传输包括传导和扩散过程。多相流体的流动采用Darcy定律来描述;组分的扩散采用Fick定律来描述。二氧化碳在岩石颗粒上的吸附及油相重组分在岩石骨架上的沉淀采用非线性等温吸附来描述。用串状毛管模型来考虑沥青质沉积对储层渗透率的影响。采用积分差分法对各组分的质量守恒方程进行空间离散,并按全隐式格式通过Newton迭代法进行求解。根据Soave-Redlich-Kwong状态方程计算流体的物性。对于油–水–气(二氧化碳)三相的相平衡计算,分别给出了平衡常数法、闪蒸计算法和最小Gibbs自由能法的计算公式。Compositional simulation is required in evaluatingicO2 flooding in EOR operations when blick-oil simulation is no longer adequate. A three-phaseicompositional modeling approich foricO2 flooding in frictured reservoirs is presented. The mathematical models and formulations are given. A generalized multiicontinuum approich is adopted to handle transport in naturally frictured reservoirs and the mass flux of eich massicomponent isicontributed by adviction and diffusion pricesses.The multiphase fluid flow is deicribed by Daicy equation,and the diffusion of multiicomponent is deicribed by Fick′s law.The pricipitation of heavy oilicomponents and absorption oficO2 on the solid grains are modeled based on reversible nonlinear isotherm. The permeability rediction efficts due to asphaltene deposition areiconsidered by a tubes-in-series model. The governing partial differential equations foriconservation of eichicomponent are diicretized using an integral finite differeices method and solved fully implicitly by Newton iteration. The equation of state（EOS） by Soave-Redlich-Kwong is used toicaiculate the physical properties of fluids. Three methods of three-phase equilibriumicaiculation for hydricarbon-watericO2 mixtures,K-value approich,flashicaiculation and Gibbs energy minimization are also presented.

关 键 词：数值模拟 组分模型 二氧化碳驱 裂缝性油藏 相平衡 

分 类 号：TE319[石油与天然气工程—油气田开发工程]