Study On The Emulsification Law Of Weak Alkali Ternary System And L Crude Oil

At present,there is no uniform standard for preparing simulated oil emulsions in the laboratory.For different oil fields,it is preferable to prepare emulsions according to their specific characteristics,and to reserve technical support for the subsequent influencing factors of emulsions.The effects of various factors on the stability and interfacial activity of L crude oil emulsion were investigated by experiments to determine the emulsification law of weak base ASP system and L crude oil.Since crude oil is rich in natural active substances such as crude oil,it is necessary to further explain the emulsification behavior of crude oil from the perspective of surfactants,and to study the effect of the complex system on the emulsification of L crude oil.For the compounding system with good emulsifying properties,the kinetic stability was analyzed and verified from the perspective of emulsion kinetics,and the compounding system with lower decomposition rate k_d of emulsion was determined.The oil displacement effect was evaluated to verify the emulsification.The extent to which the effect on oil displacement efficiency.Based on the crude oil properties of L oilfield,the simulated oil emulsion was prepared by five methods:constant temperature magnetic force,constant temperature oscillation,propeller type,intermittent high shear emulsification stirring method and hand shaking method.The oil-water ratio was 1:1,and the oil-water mixing method was adopted.The mixing is carried out successively,mechanical stirring is carried out at different shearing times and shearing strength,respectively,and the optimal combination is preferably compared by comparison:shearing time+shear rate+emulsification equipment.The effects of polymer,surfactant,sodium carbonate concentration,oil-water ratio,temperature and salinity on the interfacial activity of L crude oil and the stability of the emulsion were studied.By studying the effects of different sodium carbonate concentrations and different compounding systems KPS/LJS-2,KPS/LJS-4,KPS/LJS-6,KPS/LJS-8 on the interfacial activity of L crude oil and the stability of emulsion,it is preferred.A compounding system with better emulsifying ability.The emulsion dynamics stability model was established.Through the linear fitting,the decomposition rate k_d of the emulsion under the compound system was obtained,and the compounding system with the lower decomposition rate k_d of the emulsion was selected.The displacement efficiency of the compound system was evaluated by a displacement test.The research shows that the best combination of preparation of L simulated oil emulsion is:high shear emulsifier+shear time 20 min+shear rate 1000 r/min,the particle size is mainly distributed in 1-15?m.The concentration of HPAM,KPS and Na₂CO₃ increased,the stability of the emulsion increased,the system IFT decreased;the temperature increased,the emulsion stability became weak,the system IFT decreased;the oil-water ratio increased,the emulsion stability became stronger;the salinity increased.The stability of the emulsion deteriorates,and the system IFT decreases first and then rises.The emulsifying ability of the compound system KPS/LJS series is obviously stronger than that of the single system KPS.Among them,the emulsion prepared by the KPS/LJS-6 and KPS/LJS-8 compound system has strong stability.From the fitting results of the dynamic stability of the emulsion,the stability of the emulsion prepared under the KPS/LJS-6 compounding system is relatively strong,and the decomposition rate k_dof the emulsion is at least 0.02105.Through the analysis of the displacement experiment results,the oil displacement efficiency of the compound ASP flooding is significantly stronger than that of the ASP flooding,and the enhanced oil recovery range is 11.7%-15.3%.Formulation 0.1%KPS/LJS-6+1.2%Na₂CO₃+2000 mg/LCp has the best oil displacement effect.