| In the situation of energy crisis,Enhanced oil recovery has become an important research field.Methods of Enhanced oil recovery by surfactants and polymers have attracted considerable attention.Characteristics of dynamic interfacial tension are one of the important indexes of the performance of surfactants and polymers in EOR. Therefore,investigating the dynamic interfacial tension of surfactants and polymers in EOR in the interests of fundamental research or industrial applications is of great importance.In this paper,the dynamic interfacial tensions of different surfactants were investigated in their own field or other field.In order to know the change of dynamic interfacial tensions of different surfactants in different fields.Then,based on dynamic interfacial tensions of three surfactants in three fields were investigated,screening method of surfactant in different fields was established,Parameters of this method include the minimal interfacial tensions,concentration window and time window.Tow anionic petroleum sulfonate,nonionic sorbitan monooleate and quaternary ammonium salt gemini surfactant were synthesized.The dynamic interracial tensions of them in different fields and the mixing system of sorbitan monooleate and Tween80 were investigated.Results showed that the sorbitan monooleate and Tween80 mixtures had the best synergic effect.The minimal interfacial tensions reached 10-3mN/m.The interfacial activity of gemini surfactant is strong,in the range of 0.1%～0.8%,the stable value of interfacial tension can reach 10-3mN/m.Effect of salinity,sodium silicate,mixed alkaline,promoters and polymer on dynamic interfacial tension were studied.We were enlightened by interaction between surfactants and polymers,the graft copolymer of lignosulfonate and acrylic acid was synthesized,not only this graft copolymer has strong interracial activity,but also can increase sweep efficiency.The effects of the reaction conditions on the viscosity also were studied,the technology process and factors were determined.The results showed that the single use of graft copolymer had no obvious effect,but the mixing system of graft copolymer and surfactants had a coordinated effect.The stable value of interracial tension can reach 10-3mN/m in three fields.We also were enlightened by the molecular structure of sorbitol and the interracial property of gemini surfactant,the modified nanometer-silicon dioxide and the organic-inorganic nanocomposite were respectively prepared.Their structure and morphology were characterized by IR and TEM.The results showed that they were new surfactants which have a lot of hydrophilic group and lipophilic group on their surface. The dynamic interfacial tensions of them in different fields and the mixing system of these new surfactants and petroleum sulfonate were investigated.In the optimal conditions,the stable value of interfacial tension can reach 10-3mN/m.The mechanism of nanometer material also was studied.Finally,the uniform experimental design applied to the mixing system of surfactants.A multiple linear regression model was built by SAS software,through establishing multi linear regression model,experiments were predicted and guided.The results showed that the uniform experimental design can greatly reduce the number of experiments,enhance the work efficiency and save time and expenses.It has obvious advantage that uniform experimental design compares with traditional experimental method.The main creative points in the dissertation are as followings:The screening method of surfactant in different fields was established through their characteristic parameters.The graft copolymer of lignosulfonate and acrylic acid was synthesized,not only this graft copolymer has strong interfacial activity,but also can increase sweep efficiency.The modified nanometer-silicon dioxide and the organic-inorganic nanocomposite were respectively prepared.They have a lot of hydrophilic group and lipophilic group on their surface.The uniform experimental design applied to the mixing system of surfactants.
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