Distribution Of Remaining Oil After Polymer Flooding And Analysis Of The Influencing Factors

There is much residual oil remained in the oilfield after polymer flooding, within the area where is flooded by polymer in the oilfield, the residual oil is more decentralization, multiplicity and complexity, which is calling for higher request to the measure of residual oil digging after polymer flooding, it will be having important theoretical supports and application value for residual oil digging after polymer flooding to ascertain the features of residual oil distribution as well as it microscopic affecting factor are studied.The paper was on the base of porosity parameters which is obtained by the pressing mercury experiment of the artificial core, the 3-D network models based on which will be built. By means of 3-D network model, the organic unity of reservoir rock pore structure parameters and the microscopic seepage mechanism are obtained, and simulation the process of oil saturated,first water flooding and polymer flooding. In the process of microscopic polymer flooding simulation, the variation of the viscosity of polymer is mostly considered. Calculating the distribution morphology of the residual oil and analyzing the affecting factor of polymer flooding, the validity is proved by visualization simulation modeling experiment. The result of 3-D network model simulation has show that compared with water flooding the residual oil is decentralization, and mostly of which arranged in the formed of fascicles, but the number of fascicles oil is decrease significantly, island shape and ventilation shape increased. The bigger of the average of the pore radius, the better of the effect of polymer flooding. With the increase of the shape factor, indicating the shape of pore section is more mellow, and it is more benefit to enhance oil recovery. With the increase of the coordination number, the more path pores have, the more smooth of the liquidity of pores, the less of the percentage composition of residual oil after polymer flooding, the wettability is very important to the effect of polymer flooding, the water wetting condition is better than the oil wetting condition. Enhancing the concentration of the polymer and pressure of injection is more availability to polymer flooding.