Newsletter 3/2007

Dear Customers,

We would like to take the liberty of presenting you with our third newsletter of the year with which we want to inform you about new developments and products from Lipp Mischtechnik.

Striking Increase in Effectiveness through new Supplementary Units for Solid Matter Mixers:

Rotor/Stator-Shear Head

Horizontal or vertical Intensive Mixers, with plough blades which sweep close to the wall, or with similar paddle mixing mechanism usually have no problems mixing bulk materials of differing particle size and bulk density. Problems do often arise, however, when the mixture contains very fine powders, which, due to their particle size and shape, form agglomerates even without the addition of liquids. To assist in the mixing process, it is usually sufficient in these cases to install high-speed knife shear heads. However, when liquids are added such knife shear heads boost granulation tendencies. This effect is enhanced if by addition of highly viscous liquids even larger inhomogeneous agglomerates are created. Extended periods of exposure do not lead to disintegration, but rather to compression of the agglomerates.

Picture 1: Intensive Mixer with built-in Rotor/Stator Shear Heads

Rotor/stator Shear Heads with defined shear zones and forced material passage provide a remedy. These additional units are mounted in the lower area of the mixer chamber, where the greatest accumulation of material occurs due to the operating principle of the mixer. Basically, such Rotor/Stator shear heads can also be installed in already existing mixers.

Operating principle of the patented Rotor/Stator-Shear Heads:

The rotor of the R/S Shear Heads sucks in the material from the bulk mass at the top and the bottom side. The centrifugal acceleration presses the material through the shearing zone of the stators. Both material currents are reunited and than pushed out through the milling apertures into the bulk mass by the centrally mounted blade rotor.

The outer rotor edges form shearing gaps with the lateral webs of the apertures, which reliably disaggregate agglomerates. The central mixing mechanism continuously feeds new product into the intake zone of the R/S-Shear Heads, which also pull in larger agglomerates without danger of blockage.

Picture 2: Patented Rotor/Stator Shear Head with counter-current suction

Interesting applications for Intensive Mixers with the patented Rotor/Stator Shear Head

Plant protection:
Mixing fine mineral powders with liquid active agents.

Ready-to-bake flours:
Mixing fine powders with highly viscous additions – e.g. fats, lecithin.

Preparing pastes from oleiferous fruits:
Grinding of oleiferous fruits such as almonds or nuts

Drying of powders from solutions or suspensions:
Continuous disintegration of agglutinations and agglomerates to achieve maximum surface area.

Picture 3: Operating principle of the Rotor/Stator Shear Head

Reprocessing of chocolate rework, chocolate bars, pralines with wafer, nut or biscuit content as well as water based fillings:
Disintegration, dispersion and homogenization of the rework masses as well as simultaneous evaporation of the volatile components within a vacuum drying process.

Tests in the pilot plant facilities:
In the pilot plant facilities of Lipp Mischtechnik GmbH in Mannheim, trials can be carried out under production like conditions.

Picture 4: Vacuum Mixing Dryer with 3 built-in Rotor/Stator Shear Heads

Picture 5: Intensive Mixer in cantilever design and 2 built-in Rotor/Stator Shear Heads (for inside view see picture 1 )