Centrifugal separator having ring with outlet flow restrictions

A centrifugal separator for clarification of a liquid mixture into a heavy phase and a light phase, comprising:

• a centrifugal separator bowl rotatable around an axis and encasing a separation space, and a sludge space radially outward of said separation space;
• a hermetic inlet for feeding a liquid mixture to said separation space;
• a first hermetic outlet for a separated clarified light phase;
• a second hermetic outlet for a separated heavy phase;
• a plurality of outlet conduits extending from an outer position in said sludge space to said second hermetic outlet;
• and
• a ring having a bottom surface contacting a top surface of the centrifugal separator bowl and forming a plurality of flow restrictions extending from the bottom surface of the ring to a top surface of the ring, the plurality of flow restrictions communicating with the plurality of outlet conduits,
• wherein a diameter of the plurality of flow restrictions varies between the bottom surface of the ring and the top surface of the ring.