Chemical Oil-driven Reagents Tertiary Recovery Process Evaluation Studies Of Laboratory In Xingbei Development Zone Tertiary-main Reservoirs

Main layers has already begun a class of tertiary in industrial production in Daqing Oil Field, tertiary oil recovery and achieved good development results, and the formation of a set of systems technology. Tertiary-main reservoirs'percent of the total geological reserves of oil reserves of 64.5% in Xingbei development zone. With the water-driven development, is currently developing three types of water-drive reservoir 91.3%integrated aquifer.Alone to carry out the exploitation of water flooding, the difficulty of remaining oil potential is growing.The project researches systematically chemical oil-displacing agent used to displace Class 3 reservoirs of Xingbei development zone of Daqing oilfield, selects the injection system with application prospect. It's positive significance for exploring chemical flooding agent of EOR to displace Class 3 reservoirs of Xingbei development zone of Daqing oilfield.1. Enhanced oil recovery mechanizationThe enhanced oil recovery mechanization is to achieve maximum oil production by increasing the factor of oil recovery factor equation. Oil recovery factor equation is: Polymer flooding increases the viscosity of injected water , improves the oil-water ratio and expands macro-and micro-reservoir sweep efficiency (EV) by adding a certain amount of high molecular weight of polyacrylamide to injected water; alkali flooding and surfactant flooding lowers the oil-water interfacial tension to displace waterflood residual oil , to further reduce the residual oil saturation and improve efficiency of oil displacement (ED); ASP increase the efficiency of oil displacement (ED) by using the interfacial tension reducing agent, decrease viscous fingering by injecting fluid viscosity increase, as the water phase relative permeability of fluid towards the reduction of lead and expand the sweep efficiency (EV) to improve oil displacement efficiency.2. Experimental research in laboratory2.1Research on the feasibility of polyacrylamide floodingResearch on the Adaptability of polyacrylamide system and tertiary-main layers in Xingbei development zoneResearch on Physicochemical Performance of polyacrylamideResearch on polyacrylamide flooding2.2Research on the feasibility of functional polyacrylamide floodingResearch on the Adaptability of functional polyacrylamide and tertiary-main layers in Xingbei development zoneResearch on physicochemical performance of Functional polyacrylamideResearch on Functional polyacrylamide flooding2.3Research on the feasibility of ASP floodingResearch on physicochemical performance of ASP floodingResearch on ASP flooding 3. The results of experimental research3.1 Research on the feasibility of polymer flooding(1) The polyacrylamide solution with 1900mg/L concentration and 6 million molecular weight can pass through a core with 0.1μm2 water permeability easily. The resistant coefficient is 10～12. The remaining resistant coefficient is 2～4. The retention rate of viscosity is higher. It is suit to the third type oil layer in Xingbei development zone.(2) The viscosity of the polyacrylamide solution will increase if its concentration increases. When the viscosity is 30mPa?s, The concentration of polyacrylamide solution with 6 million molecular weight will be 1900mg/L. The retention rate of viscosity of the polyacrylamide solution with 1900mg/L concentration and 6 million molecular weight after 90 days resting is 20～30%.(3) If the man made core is used in the experiment, when 640mg/L·PV polyacrylamide solution with 1900mg/L concentration and 6 million molecular weight is injected into the core, the enhanced oil recovery ratio is 7.35%. And in the natural core situation, it will be 6.97%3.2 Research on the feasibility of functional polyacrylamide flooding(1) When the functional polyacrylamide solution with 600mg/L concentration pass through a core with 0.1μm2 water permeability, the resistant coefficient and remaining resistant coefficient are both much higher.(2) The viscosity of the functional polyacrylamide solution is higher than the polyacrylamide solution with the same concentration. The functional polyacrylamide solution has the better ability to increase the viscosity. Although the retention rate of viscosity of the functional polyacrylamide solution with 1000mg/L concentration after 90 days resting is 20～30%, the viscosity is higher than the common polymer solution because it has a higher initial viscosity.(3) The ability to increase the viscosity and of dilution after being sheared of the functional polyacrylamide solution are better than the common polymer solution.(4) The functional polyacrylamide solution can form stable emulsified mixture with the crude oil.(5) If the man made core is used in the experiment, when 640mg/L·PV functional polyacrylamide solution is injected into the core, the enhanced oil recovery ratio is 9.35%. And in the natural core situation, it will be 8.78%.3.3 Research on the feasibility of ASP flooding(1) In the system of the Weak alkali/petroleum sulfonate/polymer compound, if the petroleum sulfonate concentration is 0.05～0.4%,and Na₂CO₃ 0.4～1.4%, the 10^-3mN/m super low interfacial tension between the system and the crude oil will be formed in the third type oil layer in Xingbei oil development area.(2) The super low interfacial tension between the system and the crude oil can last 150 days.(3) If the man made core is used in the experiment, when 640mg/L·PV Weak alkali/petroleum sulfonate/polymer system(3200 mg/L polymer + 0.3% petroleum sulfonate +1.2%Na2CO3)is injected into the core, the enhanced oil recovery ratio is 11.30%. And in the natural core situation, it will be 10.97%.3.4 The optimized scheme of chemical flooding systems can satisfy the criterion of increasing the oil recovery ratio 8%.