Two H2 Iii Oil Group Polymer Flooding The Remaining Oil Distribution And Adjustment Of Tapping The Potential Research

The results from laboratory and field test show that polymer flooding can improve 8~15% OOIP, but still 50% remaining oil underground after polymer flooding. Compared with that after waterflooding, the remaining oil is less, more scattered, and fluid property is more complicated, and exportation is more difficult after polymer flooding. So how to make clear residual oil distribution after polymer flooding and how to improve development effect of polymer flooding become the present main research subject.The results from physical simulation experiments indicate that, the remaining oil which is cut apart, dispersed, retented in small pores is displaced through visco-elasticity of polymer solution and residual oil are normally enriches in the middle of pore, and water further injected diverts into small pore where oil occupys originally and residual oil is different from that after waterflooding, and residual oil are mainly remained in middle and low permeability layers and residual oil saturation is 32.8~69.6% in low permeability layers.On the basis of the results from physical simulation experiments and aimed at the complicated geological structure, longterm development features, many commingled producers and injectors, frequent operations of H2III in Xia ermen Oilfield, some numerical simulation techniques are applied to the quantitive analysis of water flooded feature and remaining oil distribution after polymer flooding, and to the determination of the main facrtors of influence on remaining oil distribution and potential distribution. It includes optimized grid, stratified control of physical properties of reservior and fluid, accurate control dynamic data, refined history matching. Based on the above remaining oil distribution and potential, improving development effect of polymer flooding and subsequent waterflooding is studied. Areally, through infilling wells, matching production and injection, oil wells converting to water, to optimize injection-production system and to improve developed reserves; Vertically, through reperforation, water shut-off, profile modification, subdivision development and injection, etc. performance adjustment measures, to increase potential in middle and low permeability layers. Performance prediction results show that productivity will improves 2.52×10~4t, oil recovery rate is more than 1.03%, steady production period is prolonged for two years, and recovery will be enhanced by 2.05% and satisfactory results will have been obtained.The paper has complished the integrated study of the remaining oil distribution combinations of microscopic with macroscopic research, of qualitative with quantitive research, potential exploitation and result prediction, which has important directive effect on adjustment and expoitation of polymer flooding for other fields.