CENTRIFUGE TYPES

1. DOWNSTREAM PROCESSING
CENTRIFUGE

2. CENTRIFUGE
• The common types of centrifuges that find
application in bioseparations include:
– tubular bowl centrifuge,
– multichamber bowl centrifuge,
– disc stack centrifuge with or without nozzle,
– decanter centrifuge and
– basket centrifuge.

3. TUBULAR BOWL CENTRIFUGE
• It is the simplest type and can provide very high
centrifugal force.
• The centrifuge can be cooled and hence is
advantageous in protein and other thermally
labile bioproduct separation.
• The centrifuge is mostly used in pilot plant level.
• It consists of a long narrow cylindrical bowl
suspended from the top rotating at high speed of
about 10,000 rpm, in an outer stationary casing.

4. • Bowl dimensions range from 8 to 15 cm in
diameter and up to 150 cm in height.
• The schematic diagram of the tubular bowl
centrifuge is shown in Figure

5. • The feed is introduced at the bottom of the
bowl and the discharge of the supernatant
occurs through an annular opening at the top.
• The feed liquid moves upward at a uniform
velocity carrying with it the solid particles.
• The solids deposit on the bowl's inner wall as
a thick paste.
• The suspension can be fed until the solid loss
in the effluent becomes prohibitive, upon
which the bowl must be dismantled and
cleaned.

6. • The trajectory of the particle and the
distances from the axis of rotation to the wall
of the centrifuge (r0), to the liquid interface
(r1) and to the particle (r ) are shown in Figure.
• At the end of the residence time in the
centrifuge, if r ≃ r0, then the particle deposits
on the wall of
• the centrifuge and if r < r0, the particle leaves
the bowl along with the fluid.
• The particle is assumed to move radially at a
terminal velocity given by equation- 9.