Experimental Research Of Reservoir Acoustic Velocity After Polymer Flooding

Polymer flooding technology is a cost-effective way to enhance oil recovery efficiency which has been widely applied and significant effected. Now generally oil fields usually use water to flood the reservoir before polymer flooding,which makes the fluid of reservoir more complex. Since the high concentration and high viscosity characteristics of the polymer solution,the change of reservoir fluid and pore structure make it possible that the acoustic characteristics of the reservoir have occured changes. Porosity evaluation method of reservoir after water flooding is applicable to reservoir after polymer flooding or not, further research and in-depth discussion are needed.This article is based on the experimental research of acoustic characteristic of polymer.It firstly studies the viscosity and acoustic properties of the polymer solution;Afterwards the acoustic impedance of rock samples in the polymer oilfield which simulated the rinse band formation. Analysis of variation of acoustic characteristics of rock samples after polymer flooding;Based on the comparison analysis of preferably pair well, focus on the contrast of acoustictime curve of reservoir before and after polymer flooding,then variation of acoustictime curve obtained. On the basis of the experimental measurements and actual comparison of the pair well,analyze and summarize the variation of acoustic characteristic after polymer flooding,and to study the impact of the strike on the reservoir parameter porosity. Finally the eventual establishment of porosity evaluation model for the study area after polymer flooding and compared the interpret results with core porosity results, and then the effectiveness of the model is tested. In brief it improved the interpretation accuracy of reservoir after polymer flooding.