Clarifier
• Purpose is removal of solid impurities (dead epithelial cells, leucocytes, dirt, dust,
microorganisms clusters) from milk prior to further processing.
• Large number of individual chambers divided by milk into thin layers. Which reduces
settling distance of foreign particles
o Increase area available for sedimentation
Separator
• Purpose is separation of fat from milk
• In principle, similar to clarifier
• Heavier (aqueous) phase (skim milk) is channeled towards the disk perimeter and
collected in space outside disk stack and routed to top outlet
• Less dense fat phase moves inwards towards center of disk.
Milk is acted upon by two forces
o Gravity
o Centrifugal
Centrifugal force is so much greater than force of gravity (that force of
gravity becomes negligible)
Specific Gravity
• Milk serum → 1.036 → (heavier)
• Milk fat → 0.93
Clarifier Separator
Removal Solid Impurities Fat
Outlets 1 (milk) 2 (skim milk; cream)
Discs Central
Perforation
Factors influencing fat content in cream (other factors kept constant)
o Speed of discs → ↑ Speed ↑ fat in cream
o Temperature → ↑ Temp ↑ fat
o Fat of incoming milk → ↑ ↑ Fat in cream
o Inflow of milk → ↓ ↑ Fat in Cream
