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Industrial Mixer Types and Terms
Types of Industrial Mixers
- commonly
mix substances with low viscosities in low-shear applications. Agitators
range in size from small agitators used in laboratory applications
to large industrial agitators with 10,000-gallon capacities.
- mix
one load of material at a time and are refilled with one load after
another.
- usually
mix miscible substances possessing comparable viscosities. Because
substance properties remain similar, blending can usually be accomplished
with relative ease.
- are
important parts of large production lines that typically have paddle
type agitators with a series of mixing stages that progressively move
and blend ingredients. Materials are constantly fed in specified proportions
into continuous mixers, then are mixed, conveyed to the opposite end
and discharged.
- are
single-shaft mixers that break apart or dissolve solid particles into
liquid using a high-speed, rotating saw-tooth blade. The blade provides
high shear forces that break apart the ingredients of low viscosity
products, such as paints.
- are
low-cost plastic spouts containing plastic mixing elements. Disposable
mixers are as efficient as most metal mixers but are not appropriate
for in-line use at high pressures.
- have
adjustable blades in a swing-blade design that maximize liquid movement
at all speeds.
- are fast mixers that use horizontal rotating shafts
with fixed arms and attached paddle-shaped feet to impact the solids
and throw some of them onto the second shaft, while pushing the rest
toward one end of the device. The paddles on the other shaft push
the solids toward the opposite end and toward the other shaft and
paddle set.
- provide
high speed rotation and centrifugal force through a perforated screen
to achieve emulsification. Emulsifiers are very effective where a high
shear is required, as they can provide fast mechanical and hydraulic
shear
- utilize
counter-current mixing, which places very high parallel forces upon
substances. During counter-current mixing, the mixing pan and the mixing
tools rapidly revolve in opposite directions, resulting in substance
uniformity.
- are continuous mixers that break down particle masses
to efficiently provide fine dispersions and stable emulsions.
- are
high-shear mixers that subject mixtures of varying viscosities to intense
mechanical and hydraulic forces, reducing mixing time and assuring
uniform blend.
- have
three or four augers and are used for quick mechanical mixing of particular
substances, especially in feed processing.
- are
being used more and more in large volume operations, as they can handle
an extremely large batch with much lower horsepower and with predictable
batch turnover. Dynamic in-line mixers utilize a combination of pump
pressure and high-speed rotating elements, while static in-line mixers
have specially contoured stationary mixing elements located in a tubular
housing that serves as part of the pipeline.
- are
an integral part of any laboratory or processing environment, as they
can perform a variety of functions, such as mixing, emulsifying, homogenizing,
disintegrating and dissolving. Types of lab mixers include compact,
dual-shaft, constant-torque and high viscosity.
- create
a uniform mixture from various combined substances.
- push
materials around the mixer.
- ,
also known as static mixers, inline mixers and pipeline mixers, are
continuous mixers that operate inline and have no moving parts. Motionless
mixers allow for the blending of two or more fluids and disperse treatment
chemicals into fluid streams.
- are
used in processing a variety of liquids, powders and crystalline solids
in the pharmaceutical processing industry. Common applications that
utilize pharmaceutical mixers include the mixing of medicine, such
as cough syrups and the creation of tablet coatings for pills.
- are
efficient, high-speed dispersion mills that can quickly disperse, emulsify,
suspend, cook, aerate and deaerate masses of particles. Material can
be put in the production mill through radial slots where they are hurled
off the slot tips against the stator slots, which produces efficient
wetting-out of the solid phase and the quick achievement of stable
suspensions, dispersions and emulsions.
- properly
mix concentrations of water to produce working and make-up solutions
for applications that include coolants, cleaners, strippers, degreasers,
fertilizers and fungicides. Venturi proportional mixers use water passing
over an orifice to create suction to draw the concentrate from the
container and mix it with water, while water-driven mixers use water
to drive a piston, which then pumps concentrate into a mixing chamber
where the concentrate is mixed with water.
- create
an extremely diverse velocity field by using a counter-transport mechanism
consisting of an outside right-hand ribbon and an inside left-hand
ribbon, both connected to the same horizontal shaft. Ribbon mixers
provide fast blending and mixing in the vertical plane, as they can
transport an entire mass of solids a short distance in both directions
of the axis of the shaft while lifting a portion of the solids a short
distance in each direction; however, they are slow when mixing end
to end.
- contain
blades that spin around the axis of the drum, mixing the substances,
such as concrete. Drum mixer axes may be either horizontal or inclined.
- includes
high-speed mixers that utilize a rotor and stationary stator to produce
high rotor tip speeds. The differential speed between the rotor and
the stator in these mixers imparts extremely high shear and turbulent
energy in the gap between the rotor and stator.
- ,
also referred to as in-line mixers, are motionless mixers that operate
continuously. Static mixers remain quite efficient and generally require
very little maintenance.
- have
either top- or bottom-mounted mixers and are used to eliminate air
pulled into the material during mixing, which increases product quality.
Industrial Mixer Terms – The recombination of finely dispersed
particles into larger particles, typically caused by a disturbance of
surface forces resulting from a change in environment.
– Salt found in the cell wall of brown algae. Alginates
are used in food processing to stabilize certain mixtures (e.g. emulsions),
to seal in moisture and to thicken texture, among other things.
– The movement of fluid from the top to the bottom of
a tank.
– Mixing process
that involves the weighing and measuring of ingredients, the creation
of a mixture from separate ingredients, the removal of the mixture and
the cleaning of the mixer and mixing tools before the start of a new batch.
– Mineralized water consisting
of sodium chloride, metallic and/or organic contaminants. Brine solutions
are utilized in food processing procedures.
– Fine particles of a substance that remain between the
dissolution phase and the suspension phase. Colloids neither dissolve
into other substances, remain suspended within the other substances nor
settle out of the substances.
– Mixing process, involving the automatic creation
of a series of mixtures, in which the mixer contains a metering mechanism,
such as a pump, and measures, combines and mixes the ingredients. Because
smaller amounts are mixed continuously, cleaning of the mixer and mixing
tools usually remains fast and easy.
– The ratio of substance mass to substance volume, measured
in g/cm3 (grams per cubic cm).
– Small particles of a substance evenly distributed
throughout another substance. Dispersed particles are small, but remain
larger than colloids.
– A suspension in which one substance is suspended within
the other. They are unable to be blended or mixed but can be combined,
though not dissolved (e.g. oil and vinegar).
– Consisting of different components that may not
be distributed evenly throughout a mixture. The components, while mixed
together, still remain separate entities.
– Consisting of identical components distributed uniformly
throughout the mixture. The components no longer remain separate entities,
but have become one entity, as in a solution.
– The part of the agitator that imparts force to the material
being mixed. Examples of impellers are propellers, turbines, gates, anchors
and paddles.
– The use of motion to create and transmit power.
– A device consisting of two rings, one stationary
and one rotating with the agitator shaft, which is used to seal against
pressure where the shaft enters the vessel. Springs or tank pressure
forces the accurately machined faces of these rings together.
– A unit of measurement equivalent to one-millionth
of a meter.
– A substance containing two or more substances that may
not be distributed evenly throughout and do not bond together chemically.
Substances in mixtures, although combined, maintain separateness.
– A two-bladed impeller whose diameter is somewhat larger
than the radius of the tank.
– The average time a component remains in a continuous-process
mixing environment.
– The breakdown of immiscible particles in a mixture
that cannot be dissolved.
– A homogenous formation created by the dissolution of
a substance or substances into another substance.
– In a solution, the liquid, gaseous or solid substance
or substances that dissolve into a liquid or gaseous substance, called
a solvent. Solutes usually consist of smaller quantities than the substance
into which they are dissolved.
– The liquid or gaseous substance into which a liquid,
gaseous or solid substance, known as a solute, is dissolved.
– A heterogeneous mixture in which fine particles of
a solid neither dissolve into a liquid or gaseous substance nor settle
out, but remain within the substance supported by buoyancy. In suspension,
both substances remain separate entities.
– The resistance of a fluid, whether liquid or gas, to
flow easily. Fluids with high viscosity, such as molasses, flow slowly;
low viscosity fluids, such as water, flow easily.
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