Abstract: A separator tank (1) comprising an essentially cylindrical vertical tank, a tangentially arranged inlet (3) in an upper part (9) of the tank, at least one first outlet (4) for oil and gas in the upper part of the tank, and at least one second outlet (5) for water in a lower part of the tank. A vortex zone (7) comprises a downward protruding conical frusta shaped wall (8) with an opening (11) at the lower end to allow communication between the upper and lower part of the tank. A helical spiralling vane is disposed on the upward directed part of said conical frusta shaped wall.

Abstract: A fluid is mixed into a mixture that has been separated from an oil well stream and comprises water, oil, and gas. The mixture comprising the fluid is led into a separator (3) and allowed to separate into a water phase and an oil/fluid phase. The cleaned water phase is removed from said separator (3) via an outlet for water. The oil/fluid phase is subjected to a separation step separating the oil/fluid phase into an oil phase and a gaseous phase from which gaseous phase the fluid is recovered by a condensation step and recycled for injection into the mixture. The separator is a liquid-liquid/gas separator (3) in which the pressure is in the range of 0.5 bar to 25 bar while the mixture comprising said fluid is separated into said water phase and an oil/gas phase.

Abstract: A gravity separator comprises a vessel within which a mixture containing water, oil, and gas can separate under gravity to form vertically discrete oil and water layers and a gas phase. An inlet duct communicates with a vessel entrance for the mixture containing water, oil, and gas. The inlet duct of the gravity separator comprises injector means injecting a gaseous medium in a volume in the range of 0.01-1.9 Sm3 gaseous medium per 1 m3 mixture into the mixture containing water, oil, and gas.

Abstract: A well fluid separator tank comprises an essentially cylindrical vertical tank (1) having an upper part (6) and a lower part (7) divided by an upward protruding conical frusta shaped wall (5), a tangentially arranged inlet (2) for fluid in the upper part of the tank, at least one first outlet (4) in the upper part of the tank, at least one second outlet (3) in the lower part of the tank, and means (12) for calming a stream around the second outlet. The upward protruding conical frusta shaped wall (5) has a first opening (8) at an upper end of said upward protruding conical frusta shaped wall to allow communication between the upper part and the lower part of the tank. The conical frusta shaped wall (5) has an inclination (9) so that the angle between the wall of the tank and the upper side of the conical frusta shaped wall is in the range from 15° to 70°.

Abstract: A separator tank comprises an essentially cylindrical vertical tank (1) having an upper part (6) and a lower part (7), a tangentially arranged inlet (2) for fluid in the upper part of the tank, at least one first outlet (4) in the upper part of the tank, at least one second outlet (3) in the lower part of the tank, and means (12) for calming a stream around the second outlet. An inner annular wall (5) has a first opening (8) at an upper end of said inner annular wall to allow communication between the upper part and the lower part of the tank. The separator tank comprises a rod-shaped vortex eye breaker (11) extending vertically at the centre of the tank in order to improve the capacity of the tank.