Research on the Performance of A Novel Compact Electrostatic Separator: from Laboratory Experiment to Oilfield Test

Water cut of oil well stream becomes high and crude oil emulsions are more stable and complex as most oilfields are in middle and late exploitation stage. It is difficult to meet the outlet oil quality requirement by using conventional electric dehydrator with bulky tank configuration in crude oil dehydration process. In this paper, we developed a novel compact electrostatic separator (CES) which combines the effect of electric field, centrifugal field and gravitational field. We firstly investigated the variations of oil content at the water outlet of CES under different working conditions in laboratory experiment. Then dehydration performance of the engineering prototype with two-stage CES were studied in the oilfield test. Oilfield test results showed the CES could effectively demulsify water-oil emulsions with water cut as high as 80%. Electric frequency has more significant influence on dehydration performance than electric voltage. Water content at the oil outlet and oil content at the water outlet of CES could be as low as 3.3% and 302.1 ppm, respectively. The laboratory experiment and oilfield test both have demonstrated good dehydration performance of CES. Results in this study can lay a solid foundation for further optimization and engineering application of compact electrostatic separator.