Useful information
Used in combination with an S 18-series dispersion tool, the drive
unit is a high-speed dispersing and emulsifying unit capable of
handling free-flowing and liquid media in batches.
Dispersion is the dissolution and diffusion of a solid, liquid or
gaseous phase in a liquid that is not consolute with that phase.
The rotor/stator principle
Due to the high rotation speed of the rotor, the medium to be
processed is automatically drawn axially into the dispersion head and
then forced radially through the slots in the rotor/stator arrangement.
The high accelerations acting on the material produce extremely
strong shear and thrust forces. In addition, high turbulence occurs in
the shear gap between rotor and stator, which provides optimum
mixing of the suspension.
The dispersion effectiveness is heavily dependent on the product
of the shear gradient and the time the particles spend in the shear
zone. The optimum range for the circumferential velocity of the
rotor/stator arrangement is 6-24 m/s.
A processing time of a few minutes is usually sufficient to produce
the desired fineness. Long processing times bring only insignificant
improvements in the obtainable fineness; the energy expended
serves merely to increase the temperature of the medium.
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Drive unit
The drive unit opens up a wide range of possibilities for dispersi-
on technology in the conventional laboratory with a respective per-
formance output of approximately 300 watts at 24,000 rpm.
The speed of the ULTRA-TURRAX
set by using the differently adjusting wheel. In order to measure
the speed of the dispersion unit an IKA DZM control tachometer
may be connected after removal of the cover (pos. 3), (see fig. 1).
Fig. 4
®
T 18 basic dispersion unit is
032007