Cream Separator

cream separator, machine for separating and removing cream from whole milk; its operation is based on the fact that skim milk (milk with no butterfat) is heavier than cream. Most separators are controlled by computers and can produce milk of almost any fat content.

The separator consists of a centrifuge in the form of a rapidly revolving bowl containing a set of disks. The bowl is mounted on a spindle situated underneath the milk supply tank. As milk enters the bowl at the top, it is distributed to the disks through a series of openings, the distributor. Thin films of milk are generated as whole milk is forced out between the disks; the milk assumes the speed of the bowl, approximately 6,000 to 8,000 revolutions per minute, and the heavier skim milk is thrown to the outer edge of the bowl and led off through an opening. The cream concentrates in the interior and moves up to the cream outlet near the centre of the bowl. The most efficient separators leave less than 0.01 percent fat in the skim milk.

A separator also acts as a clarifier. Particles even heavier than skim milk, including sediment, somatic cells, and some bacteria, are forced to the outside and collected in pockets on the side of the separator. This material, known as “separator sludge,” is discharged periodically and sometimes automatically when buildup is sensed.