EFFECT OF SURFACTANT ON RHEOLOGICAL PROPERTIES OF CRUDE OIL AND MOLECULAR DYNAMICS SIMULATION

Abstract

Abstract: Five surfactants (acrylic acid, acrylamide, maleic anhydride, vinyl acetate and styrene) commonly used as synthetic pour point depressants were selected and the effects of these surfactants on the rheological properties of crude oil were investigated by means of experiments and molecular dynamics simulation.The results showed that at the dosage of 2000ug/g, the addition of 5 surfactants had little effect on the freezing point of crude oil, which increased the freezing point of crude oil by only 1℃; but the effect on the viscosity and yield value of crude oil was significant, the relative degree of influence as follows: acrylamide>acrylic acid>styrene>maleic anhydride>vinyl acetate; compared with the blank crude oil system, the potential energy of the crude oil systems with five additives decreased, and the non-bond energy increased negatively. The order of the effect was consistent with the experimental results. The mechanism of the effect of surfactant on the rheology of crude oil was explained from the molecular level.

Key words: surfactant, solidificasion point, rheological property, molecular dynamics simulation

CLC Number:

References

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