Study On The Mechanism Of The Demulsifiers On Water And Polymer Flooding Emulsion

As this paper,the model emulsions are used to study on the mechanism of the demulsifiers on the simulating water and polymer flooding emulsion. Oil film life , thinning rate of oil film .interfacial tension.interfacial viscosity and interfacial elasticity of water-oil and their effect on demulsification of model petroleum emulsion(W/O) in the presence of demulsifiers are studied systematically. Simultaneously,the research on the mechanism of the demulsifiers are made by the structure of demulsifiers.The results of the experiments indicated that there is always no corresponding relationship between the effect of demulsifiers on interfacial tension,interfacial viscosity of water/oil and their effect on demulsification. there is corresponding relationship between the effect of demulsifiers on interfacial elasticity of water/oil and its effect on demulsification.lt indicates that in most cases the interfacial elasticity of water/oil can be an important parameter for evaluating properties of demulsifiers . the interfacial elasticity decreases with the adding of demulsifiers,which makes the strength of the interfacial film of water/oil decrease.the life of oil film shorten and interfacial film thickness thin.When the thinning of interfacial film thickness comes to a limit, the film breaks,which water separation by demulsification. For the series of NP.the higher the EO content the lower interfacial viscosity .interfacial elasticity of water/oil by them and the higher water separation per cent of emulsion.For the series of SA, the better water separation per cent of emulsion is dependent on the ratios of EO/PO,the better ration of EO/PO the lower interfacial tension.interfacial viscosity .interfacial elasticity and the better water separation per cent of emulsion. Demulsifier suitable for water flooding produced liquid may not be suitable for polymer flooding produced liquid .For polymer flooding system, Demulsifier selection is dependent on polymer concentrations in produced liquid.