Oil Recovery Effect Evaluation Of "2+3" In Block S Of Liaohe Oil Field

In this paper, as to some prominent and severe problems of Liaohe oil field, such as reservoir heterogeneity is strong, absorbent is disproportion vertically of injection wells, and in the long run the water flooding development process, the underground water is in low, ineffective water injection increase, effects of various measures annual variation, according to "2+3"enhanced oil recovery technology principle, the improve situation of block development level, water injection utilization, and enhanced oil recovery were conducted a comprehensive assessment after taking into"2+3"program, by summing up the empirical formula and theoretical formulas about implementation control and flooding of all oil fields. The results showed that the extent of flooding and water flooding recovery were improved after the water-driven tune was carried out.Taking use of numerical simulation techniques, remaining oil distribution was studied. The history matching resulted that: the calculation of geological reserves is 138.58×10~4t, the actual geological reserves is 139.10~×10~4t, the relative error is 0.37%,calculation of cumulative oil production is 26.78×10~4t, the actual data is 26.91×10~4t, the relative error is only 0.40%, a simulation of comprehensive moisture is 84.53%, the actual moisture content is 84.25%, relative error was 0.30%.Residual oil saturation of the test group well in Liaohe oil field on the uneven distribution in the plane and in the vertical plane, particularly in the vertical plane, there are contiguous plane distribution of the remaining oil, the residual oil of imperfect injection formation, the residual oil of fault block occlusion formation, the residual oil of interlayer interference formation, the remaining area between wells such on four forms.According to residual oil saturation distribution law of Liaohe oil field, respectively, considering the concentration of profile control agent and the injection time of oil displacement agent two factors, two kinds of nine "2+3" technical solutions were designed. The result which calculated by simulating the implementation of "2+3" technical solution, showed that injecting profile control agent polymer gel systems (pre-slug 2500mg/L + Lord Slug 1500mg/L + protection slug 500mg/L) 0.03PV, directly injecting drive oil surfactant (7000mg/L) 0.02PV, stage recovery of which than water displacement recovery increased by 12.2%, which is optimal solution.