Research On Emulsifying Properties Of Petroleum Sulfonate/Lipopeptide Weak Base ASP Flooding Produced Liquid

Weak base ASP flooding is the composite flooding oil production technology using inorganic weak base instead of strong base. Compared with strong base oil displacement system with NaOH as strong alkali, weak base ASP flooding produced fluid with Na2CO3 as alkali overcome the disadvantages of strong base ASP flooding that currently have been used in Daqing oil field. Little corrosion, little scaling, do little harm to the reservoir. Weak base ASP flooding produced liquid remains a considerable number of polymers, alkali and surface active agent, serious oil-water emulsion and multiple emulsion coexist, which caused difficulties for the oil-water separation. Research of Weak base ASP flooding produced fluid Emulsification Characteristics lay a theoretical foundation of weak base ASP flooding produced liquid oil-water separation technology and choice of operating parameter.The research is conductive to the application in weak base ASP flooding in oil field.The particle image analyzers detecting weak base ASP flooding emulsion type and degree of emulsification were mainly used In this paper; using zeta potential analyzer to detect electric double layer of weak base ASP flooding produced liquid.The interfacial tension meter and interfacial rheometer were used for the determination of weak base ASP emulsion interfacial tension, interfacial strength, including elastic modulus, viscosity modulus, complex modulus, interfacial viscosity. Through the study, weak base ASP flooding produced fluid has complex emulsification conditions, showing various types of emulsions coexistence which has high degree of dispersion. Internal phase particles have an average particle size is 4.48um~7um and interfacial film thickness increased, the maximum thickness can reach2.5um~3.75 um. The emulsification is between water flooding and strong base ASP flooding produced liquid. The potential absolute value of weak base ASP flooding produced fluid is between 30mV-50 mV. The interfacial tension of weak base ASP flooding produced fluid usually between 0.1~1mN/m, most of them are 0.01~1mN/m. The elastic modulus and viscosity modulus of weak base ASP flooding produced fluid are n×10-3 N/m, complex modulus is n×10-2 N/m; interfacial shear viscosity is between 7×10-4 mpa·s~10-3mpa·s.