Separator for oil, gas and water

Claim 1

A cyclone separator suitable for separating a crude oil feed containing gas and water into (i) gas, (ii) an oil rich liquid and (iii) a water rich liquid, said cyclone separator comprising a vessel having: (a) an inlet for the crude oil feed disposed so that the feed introduced under a pressure gradient is caused to form a downwardly flowing vortex of liquid from which the gas separates, said inlet being controllably variable to provide a turndown capability (b) an upper outlet for the gas comprising a pipe extending downwardly into the vessel from the top thereof to a level below the inlet, the diameter of the outlet pipe being from 0.4 to 0.8 that of the vessel in the region of the inlet, (c) a downwardly extending hollow truncated cone whose apex angle is less than 20°, located below the inlet and disposed so that its internal surface provides a surface for the downwardly flowing vortex of liquid, the vessel having an enlarged lower portion, the walls of the vessel being spaced apart from the truncated cone to define therebetween a disengaging chamber, (d) an outlet for the discharge of gas from the disengaging chamber, (e) a baffle disposed transversely with respect to the truncated cone and located between the lower end thereof and sized so as to provide a gap between its edges and the walls of the vessel, the vessel being sized so as to allow the downwardly flowing liquid to separate into an oil rich liquid layer and a water rich liquid layer, (f) a first lower outlet for the oil rich liquid and located so as to withdraw liquid from below the lower end of the cone, (g) a second lower outlet for the water rich liquid layer and located below the first lower outlet to withdraw liquid from near the base of the vessel, and (h) a deflector located within the vessel at above and below the oil-water interface as to promote the upward movement of the oil and downward movement of the water.