Study On The Effect Of Magnetic Nanoparticles On Emulsification And Viscosity Reduction Of Heavy Oil

In recent years,heavy oil viscosity reduction and drag reduction transportation technology has been tried and studied at home and abroad.One of them is oil-in-water emulsion viscosity reduction transportation technology,and stability and rheology are the key to evaluate this technology.Therefore,this paper carried out the research on the influence of amphoteric surfactant-magnetic nanoparticles emulsification viscosity reduction of heavy oil,so as to provide experimental and theoretical basis for the application of emulsification viscosity reduction transportation technology of heavy oil in practice.In this study,the water separation rate and viscosity reduction rate are the main evaluation indexes.Firstly,the efficient surfactant is selected from four different types of zwitterionic surfactants.Secondly,on the basis of the optimized amphoteric surfactant,the influence of the type and concentration of magnetic nanoparticles on the O/W emulsion of heavy oil was analyzed,so as to optimize the magnetic nanoparticles.Thirdly,the effects of p H value,oil-water ratio,Na Cl concentration,stirring speed and emulsification temperature on the stability and rheology of heavy oil O/W emulsion prepared by optimizing amphoteric surfactant and magnetic nanoparticles were systematically evaluated.Then,in order to further analyze the influence of the above factors on the rheological properties of the emulsion,SPSS software is used to analyze the variance and nonlinear regression of the experimental results of five factors and three levels,and the prediction model of pipeline pressure drop of heavy oil O/W emulsion is obtained.Finally,matlab software is used to solve the optimal value of the prediction model of pipeline pressure drop,and the main influencing factors and the optimal solution are verified by experiments.The results show that:（1）The O/W emulsion prepared by 0.5%CAB-35 and 400mg/L Co₃O₄ has good stability and high viscosity reduction rate.When the emulsification temperature is 25°C,the oil-water ratio is 7:3,and the stirring speed is 1000r/min,the 4h water separation rate and viscosity reduction rate are 30.51%and 99.41%,respectively.（2）The p H value,oil-water ratio and emulsification temperature are the main factors affecting the rheology of heavy oil O/W emulsion.When the p H value is 6.43,the oil content is 69.48%,the Na Cl concentration is 0.14mol/L,the stirring speed is 230.33r/min,and the emulsification temperature is 12.14°C,the pressure drop reaches the lowest value of 41.74Pa.After experimental verification,the model can better predict the pipeline pressure drop of the emulsion in the orthogonal experimental range.