摘要
以亲油岩石孔壁上2类残余油膜为例,从理论上研究了粘弹性驱油剂驱替油膜的微观机理。根据对壁面油膜组成及分布特征的分析,采用变参数修正的宾汉模型描述其流变性;考虑油/水相界面物理化学特性和力学平衡关系,建立了驱替壁面油膜的数学模型。对这类界面化学与力学耦合问题进行了探索性的简化理论分析和数值计算。研究结果表明,在所考察的驱替条件下,分散油膜的驱替效率与驱油剂的流变性、油水界面张力、驱替速度、油膜厚度、孔隙尺度及油膜存在方式等因素有关。在同等原油性质条件下,油膜越薄,越难被驱替;界面张力越低,驱油剂的粘弹性越大,驱替速度越大,越有利于油膜的驱替。
The microscopic mechanism of viscoelastic oil displacement a-gent is studied theoretically for displacing two kinds of oil segment remained on hydrophobic rock wall. According to the composition and its distribution characteristics of the oil segment adhered to the rock wall,modified Bingham model with varied parameters is used to describe its rheological property. Mathematical model of the oil segment remained on displaced wall is developed based on the physicochemical property and the mechanical balance relationship of oil/water interface. As advanced research, the problem of coupling of interfacial chemistry and mechanics is simplified for theoretic analysis and numerical calculation. Under the displacement conditions taken into account, displacement efficiency of dispersed oil segment is concerned with rheological property of the displacement agent, o/w interfacial tension,displacement velocity,thickness of the oil segment,pore size and occurrence way of the oil segment. For the crude oil with same property, thinner the oil segment is, harder displacement is; lower interfacial tension, greater viscoelasticity is and faster displacement velocity is, and it is more available for oil film displacement.
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2007年第1期79-82,85,共5页
Petroleum Geology and Recovery Efficiency
基金
国家自然科学基金项目"聚合物溶液微尺度流动探索研究"(50574060)的部分成果
关键词
油膜
边界层
粘弹性流体
润湿性
驱油机理
聚合物驱
oil film,boundary layer,viscoelastic fluid, wettabili-ty,displacement mechanism,polymer flooding
