Research On Optimization Design Of Depth Profile Control Scheme In Weixing Oilfield

The Weixing oil field was put into development in 2001 and has gone through three stages of development.At present,the composite water cut rate is 80%,and has entered the high water cut development stage.The composite water cut rate of the target well group is even as high as 90.5%.Serious interlayer and intra layer heterogeneity are the reservoir characteristics of Weixing oilfields.Combined with the problems of fast rising of water cut,rapid production decline,high comprehensive water cut,serious water flooding in main oil layer,scattered distribution of residual oil,and difficult to dig deep in water flooding and so on,and in order to further understand the heterogeneity of reservoir,we should focus on reducing the influence of reservoir heterogeneity to water drive development,and reduce the internal contradictions,interlayer contradictions and plane contradictions in the reservoir.Therefore,it is necessary to further expand the water flooding sweep volume and further excavate the remaining oil through the depth profile control and flooding technology,thus enhancing the oil recovery.In this paper,based on the research results of the geological,reservoir engineering of the satellite oilfield and the cost factors of the flooding agent,the compound ion polymer gel system which is suitable for the reservoir conditions of the Weixing oil field is selected.Physical simulation experiments were conducted to optimize parameters such as volume of flooding,timing of flooding,slug ratio,polymer and crosslinking agent concentration.The system was evaluated from the aspects of shear resistance,thermal stability and plugging performance.On the basis of fully understanding the reservoir characteristics,a fine 3D geological model and numerical model are established.Select the whole area and single well daily oil and comprehensive moisture content as the main fitting index to complete the historical fitting.The results of numerical simulation are used to quantify the remaining oil type,well layer and micro phase in the industrial area,and the remaining oil enrichment position can be accurately carried out,and the potential of residual oil in the block is cleared up.Considering the three aspects of reservoir geological factors,development status and construction parameters,this paper mainly studies the influence of reservoir permeability differential,displacement timing,drive radius,slug combination and other factors on the effect of deep adjustment and drive,and determines the influence degree of various factors on the effect of flood control,so as to provide some reference for the optimization of the flood control case.Finally,on the condition of the optimal adjustment and drive scheme,the effect of the whole block and well group's profile control and flooding is predicted,and the recovery rate is increased by 2.62%.