Designed for multiple mixing requirements such as high-speed dispersion, emulsification, particle-size reduction and homogenization, the Ross VersaMix Triple Shaft Mixer is now available with Solid/Liquid Injection Manifold or S.L.I.M.™ System. The incorporation of this high-speed powder induction technology adds to the VersaMix's flexibility and broadens its applicability for various formulations.
When introducing solids of low surface energy like Fumed Silica, alginates and CMC, agglomerates can form when using top-entry slow speed mixers such as propellers or turbines. In some cases, this lumping event is irreversible – subsequent shearing will not eliminate the ‘fish eyes' that have formed, restricting plant operators to very slow addition of powders which hurts production throughput. Other powders will simply resist wet-out and float on the liquid surface for hours.
Our SLIM system injects materials directly into the rotor/stator agitator of the VersaMix. The strong vacuum force above the high shear mixer sucks in powders or liquids for immediate dispersion or emulsification. As wet-out is virtually instant, mixing time is significantly decreased and the volume of air-borne particles resulting from powder dusting is minimized.
The specially designed rotor and lower flange enable direct connection of a tube to a hopper or wand arrangement. The SLIM system works well under ambient or vacuum conditions. Under vacuum, the differential pressure between the vessel's interior and surroundings creates a supplemental driving force for powder or liquid induction. In addition, incorporating ingredients under vacuum helps maintain an air-free mixture, eliminating the need for lengthy post-process deaeration steps.
At the Ross Test and Development Center in Hauppauge New York, successful medium-scale batches of various products including adhesives, coatings and resin dispersions have been produced using this technology. The final products were smooth, air-free dispersions of good consistency and up-to-standard physicochemical properties.
SOURCE: Charles Ross and Son Company