【作者】 王刚；

【导师】 王德民；

【作者基本信息】 大庆石油学院 ， 油气田开发工程， 2009， 博士

【摘要】 论文根据流变学理论、界面化学理论、流体力学理论、渗流力学理论,以提高油田采收率为研究目的,针对三元复合驱工业化应用中出现了一些问题,如三元复合驱含碱对驱油体系造成采出液处理困难、注入的碱能引起地层黏土分散和运移,导致地层渗透率下降,碱也与油层流体及岩石矿物反应,形成碱垢,对地层造成伤害并影响油井正常生产,碱还会大幅度降低聚合物的黏弹性,从而降低波及效率等,应用新研制的在无碱条件下形成超低(10-3mN/m)界面张力的两性甜菜碱型表面活性剂,开展了下列研究:实验研究了甜菜碱表面活性剂及其二元驱油体系与油的界面特性及其体相流变性,研究表明化学剂的相对分子质量、浓度、矿化度、温度等因素对驱油体系的界面特性有不同的影响规律。随着化学剂浓度的变化,一元体系与油的界面特性均有变化;二元体系中,化学剂之间的相互作用对界面黏度、界面张力、体相黏度影响程度与化学剂的浓度有关。选取波纹管模型,从能量平衡的角度出发,建立了体系的能量平衡方程,得到了无因次界面轴向驱替速度、无因次界面体积流量和无因次界面平均体积流量三个无因次量与聚合物-油之间的无因次界面张力、无因次界面黏度和润湿角的关系式。分析了聚合物溶液-油之间的无因次界面黏度、无因次界面张力以及润湿角对波纹管中油的驱替的影响。结果表明:对于波纹管中聚合物溶液的驱替,当界面的曲率方向与驱替方向相反时,聚合物-油之间的无因次界面张力以及无因次界面黏度都使上述三个无因次量降低,它们的值越大,三个无因次量降低的也越大;当无因次界面张力不变时,随无因次界面黏度的增加,平均体积流量下降。当无因次界面黏度不变时,随无因次界面张力增加,平均体积流量也下降。开展了人造浇铸和柱状岩心的驱油实验,对比分析了水驱后和聚驱后进行具有超低界面张力的表面活性剂驱、二元驱的驱油效果,定量分析了聚驱后表面活性剂驱、二元驱提高采收率的可能性。结果表明:具有超低界面张力的表面活性剂驱和二元驱均能够进一步提高聚驱后采收率,但表面活性剂驱提高采收率效果不明显,二元驱提高采收率的效果较为明显。利用可视化的简化孔隙模型驱油实验,在微观模型驱油实验中,分析了具有不同界面张力的表面活性剂驱和不同黏弹性、不同界面张力的表面活性剂/聚合物二元驱在盲端孔隙模型和仿真孔隙模型中的微观渗流过程、剩余油的分布及各类残余油的启动运移机理,研究了水驱后、聚驱后表面活性剂驱和表面活性剂/聚合物二元驱提高采收率的可能性。结果表明:表面活性剂驱和表面活性剂/聚合物二元驱均能进一步提高采收率;随着表面活性剂一元体系界面张力的降低,表面活性剂驱的采收率提高值和最终采收率都增大;随着二元体系聚合物黏弹性的增大和油水界面张力的降低,聚驱后表面活性剂/聚合物二元驱的采收率提高值和最终采收率都增大。更多还原

【Abstract】 Based on rheology, surface chemistry, fluid dynamics and fluid mechanics in porous medium theory, aimed on the enhanced oil recovery, the problems after ASP compound flooding that clay is dispersed and migrated, alkali incrustation is formed, permeability is reduced can be caused by the displacement liquid with alkali, and alkali also reduces viscoelasticity of polymer solution making sweep efficiency reduced. Using the new amphoteric surfactant that can attain ultralow interfacial tension with oil at the condition with no-alkali, following works are researched.The interfacial characteristic and the rheological property between polymer solution, surfactant solution, polymer-surfactant solution and oil are studied. The research results show that concentration, molecular weight, temperature and salinity have the effect on the interfacial characteristic of chemical solution. The concentration variety of mono-system has the effect on the interfacial characteristic between mono-system and oil. The interaction of polymer, surfactant and alkali has the obvious effect on interfacial characteristic and viscosity and the influence and effect mechanism are related with polymer, surfactant and alkali concentration on the binary system.A great deal of work is reviewed including the status of effect of interfacial behavior between polymer and oil upon displacement. An integral mechanical energy balance equation for the system is established. The relation between interfacial dimensionless axial displacement speed, dimensionless flow rate dimensionless and the relation of dimensionless average flow rate and dimensionless interfacial tension, interfacial viscosities and wetting angle between polymer and oil. We study the effect of in dimensionless interfacial tension, interfacial viscosities and wetting angle between polymer and oil upon diaplacing velocity in the undulating tube mode is analyzed. The conclusions are gained, when the direction of interfacial curvature is adverse with the direction of polymer flooding, the dimensionless interfacial tension and interfacial viscosities between polymer and oil all make dimensionless interfacial axial displacement speed, dimensionless flow rate and dimensionless average flow rate decrease, the larger its value is, the more larger dimensionless interfacial axial displacement speed, dimensionless flow rate and dimensionless average flow rate decrease. When the direction of interfacial curvature is same with the direction of polymer flooding, the dimensionless interfacial axial displacement speed, dimensionless flow rate and dimensionless average flow rate all increase with the accretion of dimensionless interfacial tension.The displacement oil experiments were finished in artificial core,the displacement oil effects of surfactant flooding and SP flooding after water flooding are analyzed with that of after polymer flooding. The probability of enhancing oil recovery of surfactant flooding and SP flooding are analyzed quantitatively after polymer flooding. The results of investigation indicate that oil recovery can be enhanced by surfactant flooding and SP flooding further after polymer flooding. But the effect of enhancing oil recovery is not obvious especially by surfactant flooding after polymer flooding, the effect of enhancing oil recovery is more obvious by SP flooding after polymer flooding.The displacement oil experiments of microscopic model were progressed, the seepage flow process of different interfacial tension surfactant flooding and different viscoelasticity and interfacial tension SP flooding is acquired after polymer flooding in the dead-end model and artificial homogeneous model. The distribution of remaining oil are analyzed, startup and moving mechanism of kinds of residual oil are analyzed. The probability of enhancing oil recovery is verified further by surfactant flooding and SP flooding after polymer flooding. The results of investigation indicate that oil recovery can be enhanced further by surfactant flooding and SP flooding after polymer flooding. The advancing value of oil recovery and final oil recovery are enhanced with interfacial tension decreasing in surfactant flooding after polymer flooding. The advancing value of oil recovery and final oil recovery are enhanced with viscoelasticity of polymer raising and interfacial tension decreasing in SP flooding after polymer flooding.更多还原