Laboratory Research On Advance Water-flooding In Low Permeability Oil Field

Based on Daqing peripheral oilfield for the study of the advanced water injection for low permeable oil fields in the interior.Advanced water injection for low permeability reservoirs similarity criterion research 26 similarity criterion,which ?10,?3,?8,?5 as the main similarity criterion,can flow oil saturation,irreducible water saturation,water phase permeability,relative position well,caliper and reservoir thickness affect indoor advanced water flooding experiment of low permeability oil reservoirs recovery degree of the key technical parameters.On the basis of similarity principle and produced a physical model,model size is 30 cm×30 cm×4.5 cm,vertical Wells using the nine point well pattern.By long core experiment of advanced water injection parameters at the same time,and tests this with the flat plate model.The experimental results show that the fuyu oil reservoir reasonable formation pressure level stood at 120%,the early production intensity is 0.356 t/d m.;Critical injection velocity is 2.4 4.19 m/d;Putaohua reservoir is reasonable formation pressure level stood at 115%,the early production intensity is 0.538 t/d m.;Critical injection velocity is 4.465.34 m/d;For low permeability reservoir,advanced water injection to achieve the same stress level,the volume of injected fluid required quantity,the lower the permeability,achieve the same advanced liquid injection pore volume multiple needed for formation pressure is larger;Indoor experimental injection-production balance,injection-production ratio of 1:1,should be carried out in accordance with the field injection-production ratio conversion,determine the injection of water compared with synchronous water injection,under reasonable pressure level,the advanced water injection in the early high produced fluid volume,early water breakthrough,but has certain inhibitory effect of water cut rise;Early production,the pressure is on the rise,near wellbore area of injection well increased speed gradually slow,middle pressure is on the decline,and decreased gradually increased,the early production well pressure near wellbore area declines,with the increase of extraction time,pressure tends to be constant;Contrast in fuyu oil layer of putaohua oil layer and the experimental result shows that the lower the reservoir permeability is more suitable for advanced water injection development mode,the need to maintain the formation pressure level is higher,the development effect is more obvious;"Adopt a low note high" core the moisture content of the moisture content of their generation "high injection low production" core overall level is low,"low injection high production" core has a long production period without water,and water cut rising slowly,to see the water has a certain inhibitory effect.Through the advanced water injection indoor experiment research can has strong guiding significance on the spot,to better development of low permeable oil fields.