Centrifugal separator, in particular sterilization separator, and method for sterilizing milk

A centrifugal separator configured to separate a flowable product to be processed in a centrifugal field into a solid phase, a first, lighter liquid phase, and a second, heavier liquid phase, the centrifugal separator comprising:

• a rotatable centrifugal drum with a vertical axis of rotation and a separating chamber, wherein the separating chamber has a radially outer solids collecting chamber;
• a separating disc pack arranged in the separating chamber of the rotatable centrifugal drum;
• a distributor arranged in the rotatable centrifugal drum, wherein the distributor comprises distributor channels and is configured to feed the flowable product from a product feed pipe into the separating chamber, and configured so that, during operation of the centrifugal separator, the flowable product is fed into the separating chamber via the distributor, wherein the distributor comprises
• first openings configured so that a first portion of the flowable product fed through the distributor is fed from the distributor channels into the separating disc pack;
• and
• one or more second openings configured to introduce a second portion of the flowable product into the rotatable centrifugal drum in an outward direction;
• discontinuously closable solids discharge openings configured to discharge the solid phase;
• a first liquid discharge configured to discharge the first, lighter liquid phase;
• and
• a second liquid discharge configured to discharge the second, heavier liquid phase.

A method for sterilizing milk with a sterilization separator comprising a centrifugal drum with a vertical axis of rotation and a separating chamber having a radially outer solids collecting chamber, a separating disc pack arranged in the separating chamber of the centrifugal drum, and a distributor having distributor channels and arranged in the centrifugal drum, the method comprising:

• i) providing the sterilization separator;
• ii) accelerating the centrifugal drum to an operating speed;
• iii) continuous centrifugal separation of milk fed into the centrifugal drum in the centrifugal drum, wherein the milk is separated into a solid phase, a first, lighter liquid phase, and a second, heavier liquid phase, wherein the second heavier liquid phase is formed from a flowable protein and germ concentrate;
• and
• iv) recirculating a first part of the second, heavier liquid phase into the centrifugal drum and discharge a second part of the second, heavier liquid phase from the sterilization separator,
• wherein, when the milk is fed into the sterilization separator, a first part of the milk to be processed is fed through first openings in the distributor into the separating disc pack and a second portion of the milk to be processed is fed through one or more second openings into a region radially outside the separating disc pack.