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Every process engineer who has worked with powders
such as fumed silica, CMC, guar, xanthan,
carageenan, alginates and other thickeners has come
face to face with one of the toughest challenges in mixing.
Many of the powders that are most often used in
the process industries are hard to wet out and mix.They
will float for hours on the surface of a liquid batch. Even
with vigorous agitation, they'll sail in circles on the
slopes of a vortex and resist being drawn down into the
batch. Once submerged, they form agglomerates that
continue to resist being separated and dispersed.
In-line mixing systems are designed to break down
those agglomerates and wet out the solids. But many
systems designed for powder induction actually create
more problems than they solve. Especially in first-generation
induction systems that combine a pump,
eductor and rotor/stator mixer, clogging and
maintenance problems can be unrelenting,
while the mixing process slows to a crawl.
The cost of mixing hard-to-disperse
powders — considering all of the processline
delays and maintenance costs that these
powders cause in the process industries — is enormous.
But today, many process engineers are looking
at these powders from a new perspective.
Precisely because powder induction is often the
cause of bottlenecks, excessive maintenance
costs and downtime, it also represents great
The quest for a new way to mix and disperse
lightweight powders began as an effort to solve one
of the oldest challenges in mixing. But the result
turns out to have much greater importance than
that. By solving numerous production problems at
once, the new SLIM (Solid/Liquid Injection
Manifold) technology for high-speed powder
induction offers gains in overall production and
The system accelerates the mixing process without
having to finance additional lines, equipment upgrades
or construction; eliminates the costs associated with frequent
clogging; and, in many cases, produces an
improvement in end-product quality.