En separatortank for separasjon av fluid omfattende vann, olje og gass, anvendelse av en slik tank og en fremgangsmåte for å separere et fluid som inkluderer vann, olje og gass

摘要

The invention relates to a separator tank in particularly suitable for separating an oil/gas phase from a water phase. Said separator tank comprises an essentially cylindrical vertical tank, a tangentially arranged inlet, at least one outlet for oil and gas in the upper part of the tank, an outlet for water in the lower part of the tank, means for establishing a calm stream around the outlet for water, and a vortex zone located below the tangentially arranged inlet and above the outlet for water, wherein said vortex zone comprises a downward protruding conical frusta shaped wall dividing the tank into an upper part and a lower part with an opening at the lower end of said downward protruding conical frustra shaped wall to allow communication between the upper and lower part of the tank, and a helical spiralling vane disposed at and secured to the upward directed part of said conical frustra shaped wall.