Abstract:

The dissipative particle dynamics(DPD) was used to simulate the emulsification and wettability alteration phenomena in the process of chemical flooding.The spontaneous emulsifications of sodium dodecylbenzene sulfate(SDBS),dodecane and three-component water system were simulated on the basis of the reasonable selection of particles and definition of interaction parameters between particles.The solid wall boundary conditions were adopted to simulate the non-spontaneous emulsification process of oil drop remained on the surface of rock under the action of hydrodynamics.The wettability alteration phenomena induced by the adsorption of surfactant on the surface of rock were investigated.The motion of residual oil drop on wetting and non-wetting rock surfaces shows that the dissipative particle dynamics,as a mesoscopic discrete particle dynamics method,provides a proper access to the problems of porous flow with physicochemical phenomena in chemical flooding for enhanced oil recovery.

Key words: enhanced oil, recovery chemical, flooding, emulsification wettability, alternation dissipative particle, dynamics mesomechanics

摘要：

利用耗散粒子动力学方法,研究了化学驱过程中乳化和润湿反转两个重要的物理化学现象。通过合理划分流体粒子和定义粒子之间相互作用参数,模拟了十二烷基苯磺酸钠、正十二烷和水三组分体系的自发乳化现象;通过附加固壁条件,模拟了在水动力作用下吸附在岩石表面的油珠发生破裂的非自发乳化过程,以及由于表面活性剂在岩石表面吸附而引起的润湿反转现象,比较了润湿反转前后残余油珠的运动情况。模拟结果表明:作为介观力学的离散粒子动力学方法,耗散粒子动力学方法可作为研究包含物理化学现象的化学驱渗流问题的重要手段。

关键词: 强化采油, 化学驱, 乳化, 润湿反转, 耗散粒子动力学, 介观力学