Change in the cold flowability and wax deposition of crude oil by weak magnetic treatment

Abstract

The research aims to study how the magnetic fields affect the cold flowability and wax deposition of the crude oil, which has been stirred by the low-intensity magnetic field for a long time. The corresponding cold flowability of crude oil can be improved under a certain level of exposure of magnetic field (60 mT with 600r/min stirring, in a 30 min exposure), which the crude oil tends to behave like Newtonian liquids. The magnetized oil could still maintain the viscosity-reduction effect when the temperature drops to a lower level, the viscosity-reduction rate was more than 10% near the pour point. What lead to the viscosity-reduction effect of magnetized oil is the promotion of the nucleation process of crystal, and subsequently, the obstruction of crystallization. It could be concluded that the weak magnetic treatment could also inhibit wax deposition based on the investigations of the deposition mass under two setups by treating the oil with or without magnetic field. Based on what has been observed in the present study, the wax who adhere to the cold finger tend to be more compact than it used to be after the magnetic treatment.