Application Note

Accelerate Bulk Powder Dispersion Into Liquid

Source: Charles Ross and Son Company

Mixing bulk solids into liquid can be challenging not only due to low solubility or resistance to wet-out/dispersion. The difficulty may simply be due to sheer volume. Certain processes call for exceptionally fast mixing of large quantities of powders such that the traditional method of adding solids from the top of an agitated tank is no longer efficient. In reality, any mixing step that normally takes hours using conventional batch mixing equipment can benefit from huge gains in productivity by shifting to a different system that can complete the batch in minutes.

High speed, high volume powder dispersion
One viable solution is the use of a specially modified rotor/stator mixer designed to generate a powerful vacuum within the mix chamber. The negative pressure produced by this type of mixer can serve to induct a wide variety of solids, from fine powders to friable pellets. In Ross mixers, this technology is called SLIM – Solids/Liquid Injection Manifold.

The inline rotor/stator SLIM mixer behaves like a centrifugal pumping device and can easily move liquid materials up to 10,000-20,000 cP. Dry solids enter from a separate port and encounter the incoming liquid stream right where materials are instantly subjected to high shear and turbulent mixing. The rotor turns at tip speeds ranging from 3,000 to 4,000 fpm and expels the mixture out of the chamber through the holes of the stationary stator.

The SLIM technology eliminates the clogging and poor dispersion quality associated with eductor-based systems. Operation is simple and the portable inline SLIM easily serves multiple process lines.