Oil Displacement Mechanism And Effect Evaluation Injecting Polymer Alternately In Pu13Oil Layer Block Xing13

With the wide application of polymer flooding technology in Daqing Oilfield, some experts have studied the mechanism of polymer viscoelastic, which fully proved the polymer can not only expand the swept volume, but also play a certain role in displacement efficiency in enhanced oil recovery.This paper studied the residual oil stress distribution in the core channel and the EOR mechanisms by injecting polymer solution alternately, deepened about the flooding mechanisms of inject polymer solution alternately.First of all, by studying the flow equations and numerical solution methods and analyzing the stress and deformation conditions of the residual oil in the different permeable layer, we can conclude that the horizontal driving force of residual oil droplets in the process of polymer flooding is about20times than that in water flooding.Furthermore, compared to general injection, alternating injection can more effectively exploit oil in low and medium permeable layer, so as to effectively expand the swept volume and oil displacement efficiency.Secondly by indoor oil displacement experiments, researching different alternating combinations and the timing.Results showed that at the same molecular weight, choose the main slug0.1PV2000mg/L, Vice slug0.1785PV700mg/Land the displacement solution of alternative4times, the displacement effect is best,In different molecular weight, choose the main slug0.1PV2000mg/L, Vice slug0.1785PV700mg/L and the displacement solution of alternative4times, the displacement effect is best.Finally contrast and analysis the same molecular weight combinations and different molecular weight combinations, we can conclude that the oil displacement efficiency of different molecular weight combinations is better than the same molecular weight combinations, And the chemical agent, economic benefit were studied, concluded that reasonable chemical agent and the optimization of slug combinations is very important for enhance oil recovery and maximize the economic benefit.