Research On Flow Mechanisms Of Polymer Elastic Microspheres In Porous Media

With the increasing demand of oil resources,and the more and more difficulty of oilfield development,so it is an effective way to enhanced oil recovery and alleviate this problem.Polymer elastic microspheres depth profile control is a new type of deep drive flooding recovery technology developed based on the characteristics of reservoir pore structure and seepage characteristics of reservoir rocks.The migration of microspheres in porous media is widely used in industrial and environmental processes such as water flooding,wastewater treatment,water purification,soil pollution and chemical separation.It has always been the field of energy,environment,health and high-tech hot topic of concern.Therefore,it is great theoretical and academic value to study the micro-flow mechanism of polymer elastic microspheres in porous media.In this paper,the appearance,particle size distribution,swelling property and viscoelastic properties of polymer microspheres were investigated by using the method of characterization of polymer materials.Secondly,the polymer elastic microspheres were studied by the sandwich tube core model in the movement of the closure mechanism and retention law.Then,the micro-migration mechanism and the mechanism of the micro-migration of the polymer elastic microspheres in porous media were studied by using the three-dimensional microscopic visualization model.The microstructures of the porous microspheres were studied by means of experimental and theoretical calculations.Finally,Study on the Change of flow pattern and flow law of polymer elastic microspheres by different fracture in simulated fracture model.The results show that the polymer elastic microspheres have good roundness and sphericity.Their particle size distribution is uniform and has good viscoelasticity,swelling property,temperature and acid and alkali resistance.The pH value of the suspension is 6.5-7.5 between.In the process of displacement,the polymer elastic microspheres can enter the core smoothly,and the pressure of the injection increases first and then the fluctuation is stable.The use of parallel sand filling model shows that the polymer elastic microspheres are preferred to flow to the large channels,causing them to block the hypertonic channels,so that the follow-up flooding fluid to achieve around the drive to achieve deep drive effect.Polymer elastomer microspheres in the sand filling tube from the entrance end closer to the polymer elastic microspheres retention more,and most of the microspheres through the simulation of the core,to achieve deep transfer effect;recovery with the polymer elasticity The increase of microsphere concentration increased with the increase of the injection rate,the increase of the degree of mineralization and the increase of the temperature.The migration of polymer elastic microspheres in porous media is mainly the migration,blocking,breakthrough and re-migration.The microstructures of the polymer microspheres and the surface of the polymer show that the influence of the degree of mineralization The higher the degree of mineralization,the stronger the gravitational effect between the microspheres and the surface of the porous media,and the more attractive polymer microspheres are adsorbed on the rock surface.The experimental results show that with the increase of the particle size and the increase of the implantation rate,the minimum injection pressure required to inject the suspension into the simulated fracture will also increase When the fracture width changes radially,the smaller the crack width will be,the front end will hold up the high pressure,and the larger injection pressure will be generated.On the other hand,when the crack width is large,the polymer elastic microspheres will be easier to move and deform.