In a method of separating a liquid mixture in a centrifugal separator, the centrifugal separator includes a centrifuge bowl arranged to rotate around an axis of rotation and in which the separation of a liquid mixture takes place; a frame which delimits a surrounding space that is sealed relative the surroundings of the frame and in which the centrifuge bowl is arranged; a drive member configured to rotate the centrifuge bowl in relation to the frame around the axis of rotation, wherein the centrifuge bowl further comprises an inlet for receiving the liquid mixture to be separated, at least one liquid outlet for discharging a separated liquid phase and a sludge outlet for discharging a separated sludge phase to the surrounding space and a vessel connected to the surrounding space and arranged for collecting the separated sludge phase discharged from the centrifuge bowl. The method includes supplying a liquid feed mixture to be separated to the inlet of the centrifuge bowl; separating the liquid feed mixture into at least one separated liquid phase and a separated sludge phase; removing gas from the surrounding space to obtain a sub-atmospheric pressure in the surrounding space; discharging a separated sludge phase to the surrounding space; collecting the sludge phase in the vessel; removing the sludge phase from the vessel; and spraying liquid into the vessel after removing the sludge phase from the vessel to reduce the level of foam present in the vessel.

In a method of separating a liquid mixture in a centrifugal separator, the centrifugal separator includes a centrifuge bowl arranged to rotate around an axis of rotation and in which the separation of a liquid mixture takes place; a frame which delimits a surrounding space that is sealed relative the surroundings of the frame and in which the centrifuge bowl is arranged; a drive member configured to rotate the centrifuge bowl in relation to the frame around the axis of rotation, wherein the centrifuge bowl further comprises an inlet for receiving the liquid mixture to be separated, at least one liquid outlet for discharging a separated liquid phase and a sludge outlet for discharging a separated sludge phase to the surrounding space and a vessel connected to the surrounding space and arranged for collecting the separated sludge phase discharged from the centrifuge bowl. The method includes supplying a liquid feed mixture to be separated to the inlet of the centrifuge bowl; separating the liquid feed mixture into at least one separated liquid phase and a separated sludge phase; removing gas from the surrounding space to obtain a sub-atmospheric pressure in the surrounding space; discharging a separated sludge phase to the surrounding space; collecting the sludge phase in the vessel; removing the sludge phase from the vessel; and spraying liquid into the vessel after removing the sludge phase from the vessel to reduce the level of foam present in the vessel.

In a method of operating a centrifugal separator, the centrifugal separator includes a centrifuge bowl arranged to rotate around an axis of rotation and in which the separation of a liquid mixture takes place; a stationary frame which defines a surrounding space in which the centrifuge bowl is arranged; and a drive member configured to rotate the centrifuge bowl in relation to the frame around the axis of rotation. The centrifuge bowl includes an inlet for receiving the liquid mixture to be separated, at least one liquid outlet for discharging a separated liquid phase and an intermittent discharge system for discharging a separated sludge phase from the centrifuge bowl. The method includes supplying a liquid feed mixture to be separated to the inlet of the centrifuge bowl; separating the liquid feed mixture into at least one separated liquid phase and a separated sludge phase; and supplying hydraulic fluid to the intermittent discharge system to initiate discharge of a separated sludge phase from the centrifuge bowl. The amount of supplied hydraulic fluid is determined by the magnitude of a generated trigger signal Tgen and the magnitude of the generated trigger signal Tgen is dependent on the air pressure around the centrifuge bowl.

In a method of operating a centrifugal separator, the centrifugal separator includes a centrifuge bowl arranged to rotate around an axis of rotation and in which the separation of a liquid mixture takes place; a stationary frame which defines a surrounding space in which the centrifuge bowl is arranged; and a drive member configured to rotate the centrifuge bowl in relation to the frame around the axis of rotation. The centrifuge bowl includes an inlet for receiving the liquid mixture to be separated, at least one liquid outlet for discharging a separated liquid phase and an intermittent discharge system for discharging a separated sludge phase from the centrifuge bowl. The method includes supplying a liquid feed mixture to be separated to the inlet of the centrifuge bowl; separating the liquid feed mixture into at least one separated liquid phase and a separated sludge phase; and supplying hydraulic fluid to the intermittent discharge system to initiate discharge of a separated sludge phase from the centrifuge bowl. The amount of supplied hydraulic fluid is determined by the magnitude of a generated trigger signal Tgen and the magnitude of the generated trigger signal Tgen is dependent on the air pressure around the centrifuge bowl.

A valve for draining off gas from a centrifugal separator includes a valve body having a central axis around which the valve may be rotated; a cavity arranged at a radial distance from the central axis and including a valve ball and a valve seat; at least one drain channel extending from the valve seat of the cavity to the outside of the valve body; and at least one gas intake extending from the outside of the valve body to the cavity. The valve ball is in a relaxed state within the cavity and thereby arranged to float on a liquid surface present within the cavity, and thereby being movable in the cavity in the radial direction from rotational axis from a closed position, in which the ball rests against the valve seat and thereby blocking gas in the cavity from entering the at least one drain channel, to an open position, in which the valve ball is at a longer radial distance from the axis compared to the closed position, and in which open position the valve ball does not block the valve seat and thereby allowing gas in the cavity to drain from the valve via the drain channel. A centrifugal separator and a method for draining gas from the inlet of a centrifugal use the valve.

A valve for draining off gas from a centrifugal separator includes a valve body having a central axis around which the valve may be rotated; a cavity arranged at a radial distance from the central axis and including a valve ball and a valve seat; at least one drain channel extending from the valve seat of the cavity to the outside of the valve body; and at least one gas intake extending from the outside of the valve body to the cavity. The valve ball is in a relaxed state within the cavity and thereby arranged to float on a liquid surface present within the cavity, and thereby being movable in the cavity in the radial direction from rotational axis from a closed position, in which the ball rests against the valve seat and thereby blocking gas in the cavity from entering the at least one drain channel, to an open position, in which the valve ball is at a longer radial distance from the axis compared to the closed position, and in which open position the valve ball does not block the valve seat and thereby allowing gas in the cavity to drain from the valve via the drain channel. A centrifugal separator and a method for draining gas from the inlet of a centrifugal use the valve.

A vacuum centrifuge (10) has a housing (15) and a vacuum chamber (14a) which is disposed in the housing (14) and is connected to a vacuum pump (26) via a suction line system (24, 48) in order to generate a required vacuum in the vacuum chamber (14a). The vacuum centrifuge (10) has a rotor (12), mounted rotatably about its rotor axis (12a) in the vacuum chamber (14a) and provided with sample container receptacles (64) for introducing sample containers (66) into the sample container receptacles (64). The vacuum centrifuge (10) also comprises a cover (16) disposed on the housing (14), closes the vacuum chamber (14a) in a vacuum-tight manner and, in the open state, frees the rotor (12) to enable loading and unloading of the rotor (12) with sample containers (66). Only one drive motor (52a) is provided for the rotor (12), disposed outside the vacuum chamber (14a) and coupled to the rotor (12) in the vacuum chamber (14a) to transmit the driving torque as part of a first drive mechanism. The rotor (12) is designed as a rotor of a dual centrifuge.

A vacuum centrifuge (10) has a housing (15) and a vacuum chamber (14a) which is disposed in the housing (14) and is connected to a vacuum pump (26) via a suction line system (24, 48) in order to generate a required vacuum in the vacuum chamber (14a). The vacuum centrifuge (10) has a rotor (12), mounted rotatably about its rotor axis (12a) in the vacuum chamber (14a) and provided with sample container receptacles (64) for introducing sample containers (66) into the sample container receptacles (64). The vacuum centrifuge (10) also comprises a cover (16) disposed on the housing (14), closes the vacuum chamber (14a) in a vacuum-tight manner and, in the open state, frees the rotor (12) to enable loading and unloading of the rotor (12) with sample containers (66). Only one drive motor (52a) is provided for the rotor (12), disposed outside the vacuum chamber (14a) and coupled to the rotor (12) in the vacuum chamber (14a) to transmit the driving torque as part of a first drive mechanism. The rotor (12) is designed as a rotor of a dual centrifuge.

A separator arrangement includes a drum with a vertical axis and which is rotatably mounted in a hooded area and placed on a rotatable drive spindle. The arrangement also includes a sealed drive area containing one or more or all of the components of a separator drive, and a pump that generates negative pressure in the sealed drive area relative to the surroundings outside of the drive area.

A separator arrangement includes a drum with a vertical axis and which is rotatably mounted in a hooded area and placed on a rotatable drive spindle. The arrangement also includes a sealed drive area containing one or more or all of the components of a separator drive, and a pump that generates negative pressure in the sealed drive area relative to the surroundings outside of the drive area.