Separation characters of an axial-flow hydrocyclone with oil collecting pipe

Abstract

In many offshore fields, water takes up 90 % of the produced fluid. The compact and efficient centrifugal pre-separation method is expected to replace the traditional sedimentation separator, which takes up a large area and is low in efficiency. The centrifugal separator can achieve rapid separation of produced fluids in the compact space of offshore platforms. However, conventional tangential inlet or axial hydrocyclone is poor-performed for high water content mixture due to droplet breakage caused by tangential inlet and unstable oil core in outlet section caused by axial inlet. In this paper, based on experiment and numerical simulation, a new type of efficient oil–water separator of high separation accuracy is constructed by the structural innovation of adding oil collecting pipe. In the treatment of 10 % oil mixture, when the inlet flow rate was 0.5 m/s, the volume fraction of oil at the oil outlet can reach 45 % and the volume fraction of oil at the water outlet can be reduced to 0.0724 %. According to the laboratory-scale tests, the novel separator shows great potential in oil field with high water content or offshore platforms.