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 separator with a rotating system includes a drum with a vertical axis of rotation, which drum is rotatable during operation, and a drum inner chamber subdivided into a lower double-conical centrifuging chamber and an upper double-conical centrifuging chamber. Both centrifuging chambers have solids discharge openings that are openable and closable in the lower centrifuging chamber by a piston slide and in the upper centrifuging chamber by an auxiliary slide. The mass moment of inertia J.sub.Q of the rotating system about a transverse axis Q extending through the center of gravity S of the rotating system of the drum and which is perpendicular to the vertical axis of rotation D is greater than the mass moment of inertia J.sub.D of the rotating system about the vertical axis of rotation D of the rotating system.

A separator with a rotating system includes a drum with a vertical axis of rotation, which drum is rotatable during operation, and a drum inner chamber subdivided into a lower double-conical centrifuging chamber and an upper double-conical centrifuging chamber. Both centrifuging chambers have solids discharge openings that are openable and closable in the lower centrifuging chamber by a piston slide and in the upper centrifuging chamber by an auxiliary slide. The mass moment of inertia J.sub.Q of the rotating system about a transverse axis Q extending through the center of gravity S of the rotating system of the drum and which is perpendicular to the vertical axis of rotation D is greater than the mass moment of inertia J.sub.D of the rotating system about the vertical axis of rotation D of the rotating system.

The method controls timing of a discharge event of a centrifugal separator, during which discharge event at least part of a heavier liquid and/or sludge or solids separated from a lighter liquid is discharged from the separator through at least one discharge opening. The discharge opening is opened and/or closed hydraulically. The method comprises the steps of waiting for a scheduled discharge time, measuring the pressure of the liquid used for opening and/or closing the discharge opening, comparing the measured pressure to a predetermined limit value, and, in the case the pressure is below the limit value, delaying the discharge event.

The method controls timing of a discharge event of a centrifugal separator, during which discharge event at least part of a heavier liquid and/or sludge or solids separated from a lighter liquid is discharged from the separator through at least one discharge opening. The discharge opening is opened and/or closed hydraulically. The method comprises the steps of waiting for a scheduled discharge time, measuring the pressure of the liquid used for opening and/or closing the discharge opening, comparing the measured pressure to a predetermined limit value, and, in the case the pressure is below the limit value, delaying the discharge event.

In a centrifugal machine, collecting chambers, which are in a rotary bowl allocated to centrifugal separation of at least two phases, include a discharge port that can be opened or closed as desired by pistons, movement of which is controlled from outside by a reduced-friction system. Drawing volume is adjustable and proportional to volume of a transverse aperture in the pistons, the ports and the openings of the collecting chambers being offset. The machine enables pseudo-continuous drawing which makes it possible to maintain a continuous supply. The drawing volume, composition of the drawn product, and compactness thereof, in a case of a near-solid phase, are controlled.

In a centrifugal machine, collecting chambers, which are in a rotary bowl allocated to centrifugal separation of at least two phases, include a discharge port that can be opened or closed as desired by pistons, movement of which is controlled from outside by a reduced-friction system. Drawing volume is adjustable and proportional to volume of a transverse aperture in the pistons, the ports and the openings of the collecting chambers being offset. The machine enables pseudo-continuous drawing which makes it possible to maintain a continuous supply. The drawing volume, composition of the drawn product, and compactness thereof, in a case of a near-solid phase, are controlled.

In a method of operating a centrifugal separator for separating at least one liquid phase and a sludge phase from a liquid feed mixture, the centrifugal separator includes a frame, a drive member and a centrifuge bowl. The drive member is configured to rotate the centrifuge bowl in relation to the frame around an axis of rotation. The centrifuge bowl encloses a separation space and a sludge space. The separation space includes a stack of separation discs arranged coaxially around the axis of rotation and the sludge space is arranged radially outside the stack of separation discs. The centrifuge bowl includes an inlet for receiving the liquid feed mixture, at least one liquid outlet for a separated liquid phase, and sludge outlets for a separated sludge phase arranged at the periphery of the centrifuge bowl. The method comprises a step a) of supplying a liquid feed mixture to be separated to the inlet of the centrifuge bowl, a step b) of determining a particle flow rate of the liquid feed mixture being supplied in step a), a step c) of determining a volume filled with particles within the centrifuge bowl based on the measurements of step b), and a step d) of discharging a sludge phase including the particles via the sludge outlets based on the determination of step b), wherein the discharge is of a specific volume or at a specific time point.

In a method of operating a centrifugal separator for separating at least one liquid phase and a sludge phase from a liquid feed mixture, the centrifugal separator includes a frame, a drive member and a centrifuge bowl. The drive member is configured to rotate the centrifuge bowl in relation to the frame around an axis of rotation. The centrifuge bowl encloses a separation space and a sludge space. The separation space includes a stack of separation discs arranged coaxially around the axis of rotation and the sludge space is arranged radially outside the stack of separation discs. The centrifuge bowl includes an inlet for receiving the liquid feed mixture, at least one liquid outlet for a separated liquid phase, and sludge outlets for a separated sludge phase arranged at the periphery of the centrifuge bowl. The method comprises a step a) of supplying a liquid feed mixture to be separated to the inlet of the centrifuge bowl, a step b) of determining a particle flow rate of the liquid feed mixture being supplied in step a), a step c) of determining a volume filled with particles within the centrifuge bowl based on the measurements of step b), and a step d) of discharging a sludge phase including the particles via the sludge outlets based on the determination of step b), wherein the discharge is of a specific volume or at a specific time point.