Study On Stability And Demulsification Of The Simulated Emulsion Of Polymer Surfactants Flooding

The polymer flooding technology,polymer flooding emulsion and polyether demulsification performance were reviewed systematically in the paper.Based on the review,four kinds of polymeric surfactant,which have already been industrialized,were selected as the research objects and the emulsification stability and demulsification performance of the polymeric surfactant simulated emulsions were systematically studied.The oil-water ratio,the concentration of polymeric surfactant and the type of polymeric surfactant have an influence on the emulsion stability of the simulated emulsions.When the ratio of water and oil was less than 3:2,the simulated emulsion was mainly W/O,and the stability of the emulsions increased with the increase of the ratio of oil and water in the system.When the ratio of water and oil was 1:4,the simulated emulsion was mainly O/W.The order of the emulsifying ability of four kinds of polymeric surfactant is:(O/W)demulsifier,II demulsifier,BIII demulsifier,I demulsifier.The emulsification stability of the simulated emulsion increased with the increase of concentration of the polymeric surfactant.The results of the study on the strength of the film,the interfacial tension of oil-water interface and the viscoelasticity of the oil-water interface showed that the polymeric surfactant with the structure of polymer and surfactant could adsorbed on the oil-water interface,and reduced the interfacial tension of oil and water,which led to form a stable interfacial viscoelastic film.And the stability of the simulated emulsions increased.Moreover,the stability of the interfacial film increased with the increase of the concentration of the polymeric surfactant.The demulsification of series of polyether demulsifiers on the O/W polymeric surfactant simulated emulsions were investigated.The results showed that a series of polyether demulsifier has a certain demulsification effect on the emulsions of four kinds of polymer flooding emulsions.But the water content of oil and the oil content of water after demulsification didn't meet the requirements of the enterprise,and the demulsifier J-782 has good water separation efficiency,the water content of oil was lowest after demulsification by the demulsifier B-623 and the oil content in the aqueous phase was the lowest after demulsification by the demulsifier F-181.The demulsification of series of the compound demulsifiers on the O/W polymeric surfactant simulated emulsions were also investigated.The results showed that when the concentration of the demulsifier is increased to 150mg/L,the compound demulsifier FP-6 andthe compound demulsifier FP-1 have good demulsification effect on the emulating emulsion of the polymer flooding and the oil content of the water phase after demulsification was lower than 240mg/L and the oil content of the oil phase was less than 30%.The difficulty of demulsification of the emulating emulsion increased with the increase of the concentration of the polymeric surfactants.When the concentration of the polymer is lower than 200mg/L,the oil content of water and the water content in the water met the requirements of the enterprise after demulsification.