Research On The Displacement Law Of Heterogeneous System Under Heterogeneous Conditions

Polymer oil displacement agent and gel particle profile control agent have been widely used to stabilize oil production and control water cut in oilfield.In order to solve the limited swept volume of polymer solution in serious heterogeneity reservoir,and the complicated injection process of pre-crosslinked particle,research group has developed a kind of heterogeneous system with gel and water soluble polymer double characteristics.This thesis research and solution properties of heterogeneous system and solution in the condition of homogeneous and heterogeneous conditions of migration rule are studied,for such the development and application of oil displacement agent provides a theoretical basis.With dual characteristic of gels and polymers,the heterogeneous system’s molecular structure contains a large number of branched chains.The heterogeneous system solution showed the effect of particles viscoelastic and viscous hydration layer.Based on the performance research of the heterogeneous system solution,the study found the heterogeneous system has rheological property,viscoelasticity,and the particle size distribution of the heterofeneous system is relatively uniform,the mesh number of the heterogeneous system has little impact on the performance,Mechanical shear effect on the rheological properties of heterogeneous system is small,and the perforation shear effect on the rheological properties of heterogeneous system.This paper has researched on the law of displacement in porous media of the heterogeneous system,and measured of the injection of the heterogeneous system in the one dimension sand filling tube,matching atrribute,the mobility control capacity,the changes of produced fluid and oil recovery.The results showed that:①the transportation of the heterogeneous system in porous media was by the way of alternate plugging and flooding which was accumulated plugging,pressure lifting,deformantion transporting;②Through mobility control and matching confirmed heterogeneous system only match the pore throat of porous media,to establish the best resistance coefficient and residual resistance coefficient,improve recovery efficiency is highest,profile control effect is best,should be considered in the process of practical application to the particles and the matching of pore throat;③By produced fluid found after porous medium shear heterogeneous system,the particle size increased with the increase of migration distance showed a trend of decrease,the elastic modulus decreases,and the viscous modulus increases,the produced fluid is given priority to with viscous modulus.By investigating the heterogeneous system under the condition of heterogeneous displacement law of research findings:①Fluid diversion and the mobility control capacity of the heterogeneous system improved the reservoir heterogeneity,decreased the absorption fluid volume in the high permeabibity formation fluid,and increased it in middle and low permeability formation,Have a good profile control effect;②30～50 mesh heterogeneous system can significantly improve the medium and low permeable formation oil recovery,and 100～150 mesh heterogeneous system due to the particle size is limited,can significantly improve the high permeable formation oil recovery;③Through the heterogeneous system in three-dimensional oil saturation in physical model study has found that heterogeneous system in three-dimensional physical model has better ability to expand sweep.