Research And Application Of Particle Sealing Simulation And Profile Control System

The position of the particle profile control agent in the pore throat determines its influence on the pressure difference of the throat,which in turn causes the sealing of the injected water to be diverted,guiding it to the remaining oil enrichment area,and finally improving the effect of profile control and water shutoff.At present,the research on the particle profile control mechanism focuses on the digital-analog derivation,and the lack of intuitive process presentation.In the experimental research part,there is still a lack of research on the combined profile-distribution cooperative displacement system,so the establishment of particle-blocking pore throat The model has a positive effect on the application of particle profile control.Eight basic pore throat models are designed according to three characteristics of sand body size,sand body gap and sand arrangement symmetry.The pressure field distribution and profile control agent when the flow field was stabilized after the profile control agent was plugged were studied by using COMSOL Multiphysics software.Block transient velocity field disturbances.Through the microscopic visualization of the displacement experiment,the migration state of the particle profile control agent between the pore throats was studied.After basic screening experiments such as the effective flocculation volume test of bentonite-polymer suspension and the particle size measurement experiment of microsphere particles,the effect and mechanism of the profile control plugging of the single injection of bentonite particles and the separate injection of microsphere particles were studied,and then the particles were developed.The double parallel tube experiment of the profile control agent and other profile control water-blocking agents was injected to analyze the sealing mechanism of the combined profile control under the condition of heterogeneous formation.On this basis,based on the 22F block characteristics and oil-water parameters of Shengli Chengdao Oilfield,a homogeneous low permeability but high permeability water channel mechanism model was established to study the profile control agent slug combination,the amount of profile control agent,The effects of injection pressure,injection speed and other factors on the oil control effect of the reservoir.The results show that when the particle profile control agent is used to seal the eight basic pore throat models,the pressure difference between the left and right flow channels of the pore throat structure is increased by different sealing methods,and the pressure difference increase rate is 19%-74%.Blocking large holes is better for improving the differential pressure than sealing small holes.Blocking the flow path between the large sand particles is better than increasing the pressure difference between the small sand particles.The larger the sand body gap is,the smaller the ratio of the sand body particle size to the sand body spacing is,and the more obvious the pressure difference of the sealing hole throat is.It is better to block the equal-diameter sand body than to block the non-equal diameter sand body.The grain size of the sand body,the gap of the sand body,the symmetry of the sand arrangement,etc.all have an influence on the disturbance of the transient flow velocity field of the particle profile control agent to block the pore throat.The larger the particle size,the larger the particle spacing and the sparse distribution of the surrounding velocity field.The smaller the sand spacing,the finer the sand,and the faster the initial velocity of the flow through the channel.The symmetry of the particle distribution,the distribution of the velocity field is also asymmetrical.In the experimental study of the particle profile control system,under the condition of heterogeneous formation,the particle size profile matching agent and the pore throat matching degree also have an important influence on the enhanced oil recovery.The subsequent enhanced oil recovery combined with other profile control agents is 15%-20%higher than the subsequent enhanced oil recovery by separate injection.On this basis,using Eclipse to carry out the mechanism digital model study of the Shengli Chengdao block,the particle profile control construction design scheme is proposed,that is,using the profile control agent multiple rounds of combination sealing,blocking 50 grids,wellhead injection pressure 30 MPa,injection speed of 100 m~3/d,to provide appropriate guidance for on-site construction applications.