Method and a Device for Separating a Multiphasic Liquid

A liquid/liquid separation cyclone for separating two liquid phases of different densities in a fluid, in particular aqueous and oil phases in crude oil, the cyclone comprising:

• a separation chamber having a wall that forms a surface of revolution that extends between:
• at least one tangential admission orifice for the fluid to be separated and a top axial outlet orifice for the lower density liquid phase at the top end of said chamber;
• and
• a bottom outlet orifice for the higher density liquid phase;
• the cyclone being characterized in that said separation chamber comprises a single cylindrical body extending at least between said admission orifices and a platform on the same axis as said cylindrical body, the platform being of diameter smaller than that of said cylindrical body and being positioned over said bottom outlet orifice, such that two volumes are created under the effect of the fluid for separation entering via said tangential admission orifice(s), the volumes comprising a central volume of lower density liquid phase, in particular oil phase, in the form of a substantially cylindrical central column supported by said platform, and an annular peripheral volume of the higher density phase surrounding said central column, enabling the lower density liquid phase to be discharged via said top axial outlet orifice and said higher density liquid phase to be discharged via said bottom outlet orifice.