低渗透油藏岩心级别小尺度微乳液驱数值模拟研究  

Core-Level Numerical Simulation of Microemulsion Flooding in Low Permeability Reservoirs

作　　者：刘志丽 LIU Zhi-li(International Exchange and Cooperation Division of Northeast Petroleum University,Daqing 163318,China)

机构地区：[1]东北石油大学国际交流合作处,大庆163318

出　　处：《当代化工》2021年第2期408-413,417,共7页Contemporary Chemical Industry

基　　金：国家自然科学基金,低渗透油藏表面活性剂驱微乳液渗流机理及数值模拟研究(项目编号:51474071)。

摘　　要：基于低渗透油藏微乳液驱油特点,建立了用来研究低渗透油藏的驱油机理的微乳液驱的三维三相5组分的渗流数学模型,在模型中对表面活性剂分子的吸附和扩散特征进行了考虑。并且在此模型中,采用考虑启动压力梯度的非达西渗流方程表征微乳液驱渗流规律,能够体现低渗透油藏渗流特点。根据室内实验,确定出非达西渗流方程中的有关系数,测定了微乳液相黏度、油水相对渗透率和吸附参数,并建立了这些参数的数学表达式,它们被作为辅助方程。采用隐式差分方法得到该模型数值解,并编制了相应的计算机数值模拟软件,进行了相应模型的数值模拟计算。获得了压力拟合的相对误差为3.26%,流量拟合的误差为2.72%,含水率的拟合误差2.56%。实验与理论计算表明,微乳液体系能够降低启动压力梯度0.011 MPa·m^(-1),注入压差降低0.62 MPa,含水率最高下降达到了34个百分点,采收率则提高了10.9个百分点。A three-dimensional three-phase five-component percolation mathematical model of microemulsion drive was developed to study the oil-driving mechanism of low permeability reservoirs based on the characteristics of microemulsion drive in low permeability reservoirs. In this model, the non-Darcy flow equation, which considered the starting pressure gradient, was used to characterize the percolation of microemulsion drive, which could reflect the percolation characteristics of low-permeability reservoirs. The coefficients in the non-Darcy seepage equation were determined based on the experiments in the room, and the microemulsion phase viscosity, oil-water relative permeability, and adsorption parameters were determined and mathematical expressions for these parameters were developed. The numerical solution of the model was obtained using the implicit difference method, and the corresponding computer numerical simulation software was prepared and numerical simulation calculations of the corresponding model were performed. The fitting relative errors of the pressure, flow rate and moisture content were 3.26%, 2.72% and 2.56% respectively. The experimental and theoretical calculations showed that the microemulsion system was able to reduce the threshold pressure gradient by 0.011 MPa·m^(-1), reduce the injection differential pressure by 0.62 MPa, reduce the water content by up to 34%, and enhance the oil recovery rate by 10.9%.

关 键 词：微乳液驱 启动压力梯度 数值模拟 渗流数学模型 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程]