Study On Reconstruction Strategy Of Seepage Field In High Water Cut Stage Of S Oilfield

At present,the S oilfield is in the stage of “high water cut and high recovery”.The distribution of remaining oil is complex,and the overall characteristics of “extended dispersion and local enrichment” are presented.It is more difficult to continuously improve the development effect of oilfields.Therefore,it is necessary to describe and evaluate the current seepage field and formulate corresponding reconstruction plans.In order to achieve the purpose of clarifying the characteristics of the target oilfield in each development stage,the physical simulation laboratory experiments are carried out from three dimensions: one dimension,two dimensions and three dimensions.Considering the seepage characteristics and static characteristics of the plane wave sum coefficient and the longitudinal wave coefficient,respectively,the corresponding theoretical calculation formula is deduced,and the sensitivity analysis of the main influencing factors is carried out.A representative characterization index-surface flux was selected from a number of static and dynamic factors affecting the seepage field.The intensity of the seepage field was graded by fuzzy C-means clustering analysis method to establish a complete seepage field evaluation system.Considering the phenomenon of physical property time-varying,the corresponding modules are compiled in FORTRAN 90 language.On the basis of the potential development of the target oilfield,a variety of seepage field reconstruction measures are proposed,including: well network adjustment diversion line,layered deployment equilibrium drive,potential layer open layer production,liquid extraction,single well injection concentration Optimization and other measures.The results show that the combination of indoor experiments and theoretical derivation determines that the recovery rate of the target oilfield is more than 55%,indicating that the target oilfield has great development potential at this stage.Through the study of plane wave and coefficient sensitivity,it is found that the smaller the starting pressure gradient is,the larger the pressure difference is,the smaller the plane permeability difference is,and the larger the plane wave sum coefficient is.Through the sensitivity of the longitudinal sweep coefficient,it is found that the larger the coefficient of variation of permeability,the larger the oil-water viscosity ratio and the smaller the longitudinal sweep coefficient.The results of the seepage field reconstruction scheme show that when the source direction is consistent with the direction of the well row,the development effect is better;the measures of layered water injection,liquid extraction and opening layer can also effectively improve the development effect;Reasonable concentration of polycondensation.Finally,the ineffective water circulation of the dominant seepage field was effectively alleviated.The remaining oil at the non-dominant seepage field was effectively used,the utilization rate of the injected water became higher,the effect of injection was more obvious,and the development effect was significantly improved.