BLENDING & MIXING TECHNOLOGY
Selecting the right blender for
powder mixing plants One of the most significant functions and consequently one of the most important aspects in a powder processing system is blending. In this article we look at how to increase value of products in food applications - whether manufacturing sports nutrition products or bakery or anything in between.
A
growing challenge in the powder handling industry is how to accommodate a wide portfolio
well here, such as tumble-blending or ribbon blending. • On the other hand, for cohesive, sticky
of recipes and vast array of different
powders to mix homogeneously, work
ingredients, several of which pose an
needs to be applied to the material,
allergen risk. Some companies have been
forcing the particles to fold and join. In
willing to spend significant amounts of
this case, blenders offering high shear
capital installing highest speed mixers
in the form of knives or intensifiers are
and packing lines in order to achieve
required. Applying the right amount of
high efficiency and throughput. But just
shear is vital to intermesh and blend
because a mixer is high speed, does it
the particles, however, if mismanaged,
necessarily mean that it provides the best
particle degradation and heat build-up
process solution?
may occur.
Whether you are just getting started, or are a seasoned professional, the choice
BATCH SIZE
of mixers is so vast that the process can
• B ig isn’t necessarily beautiful for
become very confusing. This article poses
blenders. It might be large enough to
some questions to be considered when
match the order amount and batch size
making that all important selection.
but watch out for loading times. Take
Before we get started, the most
into account how long it will take to fill
The Matcon IBC Blender module enables the mixing of any recipe, at any time
important decision is whether to batch or
by ripping and tipping 25kg sacks of
continuously manufacture. Do you need
ingredients. Then think about how long it
operation. It might well only take four
to swap recipes on a regular basis or are
will take to empty the product to packing.
minutes to blend, but it could take two
you producing the same product day in
During this time the mixer will stand idle
hours to load and three hours for packing
day out? If there are no changes to be
and be unproductive which is not Lean.
to call off. Giving a total blending time of
made, then it makes sense to consider
Companies often do not realise the cost
continuous processing with large fixed
of this lost time in filling and emptying the
mixers which are coupled to the upstream
mixer. But it should be challenged for the
longer for the blend cycle (often 10 to
and downstream processes.
waste that it clearly represents.
15 minutes), but in the long run you save
As a lot of manufacturers are finding
• A lso consider whether you will have
five hours and four minutes. • In-bin/IBC Blending might take a little
time as formulation of the recipe is done
however, consumer desire for more variety
different batch size demands. Do your
off-line and the container is removed
means more and more recipes being added
customers always want the same size
immediately from the blender and
to the ever expanding product portfolio.
orders? Do you have to make small sized
taken off to packing. The filling, mixing
The consequence of which is more recipe
batches of half or a quarter of the large
and packing process steps take place
changes than ever before and means you
batches? If you have wide variability
simultaneously. The blender itself doesn’t
need to take a close look at how you plan
consider using IBCs (Intermediate
need cleaning so it is free to go back into
to conduct mixing. Here batch processing
Bulk Container) Systems for blending,
service immediately. The only limiting
is the only way. The points raised in this
whereby different sized containers can be
factor is how quickly your operators
article refer mainly to the case for batch
accommodated on the one blender.
can install and remove the bins from
processing as it is assumed this is an expanding area of consideration.
the blender.
MIXING TIME • Don’t be fooled by claims of only a four
CHANGEOVER TIME
POWDER CHARACTERISTICS
minute blend time. It’s important to
• If you are making several recipe changes
• A free-flowing powder with similar
weigh up the full end to end process
throughout the day, using a fixed mixer
ingredient particle sizes will mix easily.
stage of blending, from filling the mixer to
can be inflexible. You will need to
A gentler blending approach will work
it being emptied and ready to go back into
conduct a clean-down each time, thereby
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June 2021 | FOOD RE VIEW
