Influencing Factors And Laws Of Polymer Solution Properties In Core

According to the problem of dramaticly changing of polymer solution properties in the process of polymer flooding in oil reservoir,and it's difficulty to accurately predict,mainly conducted by means of experiments,the research on the influence factors and rules of changes in properties of polymer solution cores is carried out.The main research contents are the thermal degradation and chemical degradation characteristics of polymer solution,the influence of mechanical degradation on the viscosity of polymer solution,and the distribution of polymer solution in the long rock.The results show that the polymer solution viscosity loss caused by chemical degradation in polymer flooding process is relatively small,about 5%;thermal degradation caused by the viscosity loss of about 10%,mainly occurred in the first 5 days;in the end of injection(injection wells)near the main reason for the viscosity loss of polymer solution is the mechanical degradation,mechanical degradation of viscosity loss rate is above 30%,which the tensile shear degradation is the principle category,degradation as a supplement;by introducing the concept of regional PV number,according to the experimental results to determine the core polymer retention volume reached saturation in the critical region of PV(PV_L);in the end away from the injection(injection wells)in deep reservoir,when the injection volume is less than PV_L,the main factorsof polymer solution viscosity decline is the concentration retention;According to the experimental results,the viscosity of polymer solution,resistance on the polymer molecular degradation and retention which led the distribution law of force coefficient in the core of long rock is discussed,which lays a foundation for deducing the distribution of polymer solution for oil displacement in actual reservoir.