Higher Concentration Polymer Flooding And The Mechanism Of Reducing Injection Pressure With Surfactant

The macroscopic and microscopic oil recovery mechanisms were studied by the experiment of etched glass and physical analogue models. Through the adsorption characteristics of surfactants on Daqing oil sand,the injection pressure reduction mechanism of the surfactants are probed. A new surfactant of polyoxyethylene polyoxypropylene ether carboxylate of fatty alcohol is synthesized.In etched glass model,the residual oil displacement course is examined with higher concentration polymer flooding.The method that get the displacement efficiency of polymer elasticity is given by studies the HPAM and Folcon4800 permeability characteristic in poros medium respectively.Through interfacial tension of several surfactants and the injection pressure reduction,the relationship is found out between them. The adsorption behavior of anionic and nonionic surfactants were measured with two phase titration method and visible spectrophoto metry respectively. The injection pressure reduction is correlated to the surfactant adsorption on oil sand .The adsorption of polymer on sand decreased after the surfactant absorbed,the adhere force between polymer and sand decreased ,the injection pressure droped.The relationship between reducing injection pressure and surfactant foaming ability is discussed.Polyoxyethylene polyoxypropylene ether carboxylate of fatty alcohol is prepared with polyoxyethylene polyoxypropylene fatty alcohol as raw materials by the method of carboxy methylation.Through the studies on the effect of reaction temperature, reaction time and the ratios of reactants, the relatively optimum reaction conditions are obtained. The interfacial activity is improved .