Study On The Polymer Selection And Its Properties Evaluation In ASP Flooding

In this paper, six different kinds of polymers(Refinery polymer of molecular weight of 19 million, 25 million, 35 million, homeo-polymer, Japan MO4000 and France 3630)were used to prepare relevant ASP ternary system respectly . By checking their phase stability, interfacial tension ,viscosity and the stability before and after shearing, we evaluated the compatibility between the polymer and surfactant and selected the polymer types which are suitable for the field application.By testing the viscoelastic of different ASP ternary system prepared by different types of polymer under different conditions, we evaluated the viscoelastic of these ASP system, it will povide the basic datas for the field application. By doing some flowing experiments and physical model experiments of different ASP ternary system prepared by different types of polymer in homogeneous artificial cores, we evaluated and selected the types and concertration of polymer and optimal injection methods which are fit for ASP flooding in he 1st or2nd oil reservoir.It shows that the compatibility between the polymer and surfactant and the viscoelastic of ASP system prepared by Refinery polymers of molecular weight of 25 million or 35 million are both better when compared with the better quality polymer abroad and they are available if blockage problem did not occur in the oil reservoir.The ASP system has a good ability to expand the swept volume when the concentration of ASP system increasing. Considering various factors and the field application, Refinery polymers of molecular weight of 25 million or 35 million are decided to be the optimal polymer types and two optimal injection methods can be obtained: One is that the main slug injection of ASP system is 1.2% A + 0.3% S + 2000mg/L PAM, the other is that firstly injecting 0.1PV 1.2% A+0.3% S+2000mg/L PAM ASP 0.3PV and then injecting 0.15PV1.0% A+0.1% S + 2000mg/L PAM based on the amount of the main slug injection of ASP system is same.Furthermore, flooding experiments of ASP system prepared by optimization formula and optimal injection methods in the natural core were investigated, it furtherly verifies the ability of ASP can enhanced oil recovery and the following conclusions have been obtained: (1)The flooding efficiency of ASP system prepared by Refinery polymers of molecular weight of 25 million or 35 million is best and EOR is larger; (2)high viscoelastic and interfacial activity of ASP system both can enhance the Flooding efficiency.