Study On Characteristics Of Adsorption And Retention Of Amphiphilic Polymers And Surfactants On Rocks And Minerals

In the actual development and application of oilfield, the loss of displacing agents is oneof the key factors in the success of complex chemical flooding. The research of adsorption ofamphiphilic polymer and surfactant systems on rocks and minerals can not only improve theunderstanding of the interaction law between them, but also have great importance tooptimize the prescription of polymer/surfactant systems and promote the EOR technology.The performance of optimized amphiphilic polymer/surfactant binary system has beenevaluated by means of viscometric and rheological method. The static adsorption isotherms ofdisplacing agent components in the binary system on three types of rocks and minerals havebeen obtained, and the influences of various factors on static adsorption have also beenexplored. And the difference between the adsorption kinetics of the binary system on the corewith oil and without oil has been analyzed.The factors affected the1500mg/L AP-Ⅲ+0.01%HF-E binary flooding system havebeen studied: with the increasing of salinity, the viscosity and elastic modulus G’ of the binarysystem increase at first and then decrease, reaching the maximum when the salinity is4000mg/L; when the divalent metal cations of Ca2+and Mg2+exists alone, the solutionproperties exhibit different trends, while when the two ions coexist, the regularity is veryclose to that of Mg2+exists alone; and as the temperature increases, the viscosity of the binarysystem shows a downward trend.The static adsorption isotherms of amphiphilic polymer are combined by L style and Hstyle on three rocks and minerals of quartz sand, kaolin and clay, and the static adsorptionisotherms of surfactant are in line with the Langmuir type. Amphiphilic polymer andsurfactant show competitive adsorption relationship, and the adsorption amount of bothdisplacing agents on three types of rocks and minerals is clay> kaolin> quartz sand; with thesalinity increasing, the static adsorption amount of amphiphilic polymer slightly decreases at first and then increases, while that of surfactant increases monotonically, and as temperaturerises, the static adsorption amounts of amphiphilic polymer and surfactant both exhibit anincreasing trend.The core circulating displacement experiment indicates that the dynamic adsorptionamount of amphiphilic polymer/surfactant binary system on the core is less than the staticadsorption amount of that, and the adsorption amount on the core with oil is also less than thaton the core without oil.