RESEARCH ON CO2 MISCIBLE FLOODING TO ENHANCE OIL RECOVERY IN LOW PERMEABILITY RESERVOIR

Basis on the development problems of Yushulin low permeability oil field,and in order to verify suitability of CO2 Miscible Flooding to this kind of reservoir,a series of experiment about CO2 displacement in slime tube,core and numerical simulation were developed,obtained minim miscibility pressure of Yushulin Oilfield,the experiment and numerical simulation results of recovery rate with different displacement in core can get well coincidence,and get flowing conclusion:the CO2 displacement can be used in Yushulin Oilfield,anhydrous miscible flooding in core can enhance 19% of recovery ratio and gas-water alternative displacement can improve 10% to 19%.Injection a suitable volume of gas can decrease the affection of water and enhance oil recovery ratio.