Enhancement of flow characteristics in waxy crude oil under the influence of subtle magnetic fields

Abstract

The study aims to improve flow in weakly magnetized transportation of waxy crude oil. The magnetization of waxy crude oil with a weak magnetic field strength below 100 mT was investigated using magnetization processing equipment. By employing the orthogonal experimental principle and data processing method, the magnetization effect of crude oil and its primary influencing factors were examined and analyzed. A new concept, equivalent viscosity reduction rate, is introduced along with criteria for evaluating the effectiveness of reducing magnetization viscosity. The equivalent viscosity reduction rate increases as magnetization intensity rises, but initially increases and then decreases as magnetization temperature increases. The viscosity reduction is most significant when the magnetization temperature is close to the wax appearance temperature, resulting in an 18% equivalent viscosity reduction rate. We clarify the mechanism of enhancing crude oil flow with magnetic fields by integrating previous microscopic studies. The viscosity reduction effect of magnetized wax crystals is orderly under a weak magnetic field. The nucleation of magnetic wax limits the viscosity reduction effect of magnetization at high temperature. The reduction in the length-diameter ratio of magnetized wax crystals and boundary box dimensions contributes to enhancing the low temperature fluidity of crude oil.