Mixing # pharmaceutical engineering # pharmaceutical technology # STATISTICAL PARAMETERS # FACTORS INFLUENCING MIXING # V CONE BLENDER # DOUBLE CONE BLENDER # RIBBON BLENDER # SIGMA BLADE MIXER # PLANETARY MIXER # AIR MIXER OR FLUDIZED MIX #

1. PREPARED BY
L.GOPI M.PHARM.,
DEPARTMENT OF PHARMACEUTICS
K.BHARATH KUMAR B.PHARM SECOND YEAR
561990009
MIXING
PHARMACEUTICAL
ENGINEERING

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MIXING
 Mixing is defined as a process that tends to result in a randomization of dissimilar
particles with in system.
 Some of the mixing operations in the dispensing practice are spatulation , trituration
, tumbling , geometric dilution etc.,
 A major complication in the intimate mixing of particles is the segregation of
particulate solids that result from gravitational effects on the agitated bed.
 Mixing can also be achieved by milling , kneading etc.,
 There are significant differences between solid mixing & liquid mixing.
LIQUID MIXING:
 Flow currents are responsible for transporting unmixed material to the mixing
unmixed material to the mixing zone adjacent to impeller.
 Truly homogeneous liquid phase can be observer.
 Small sample size is sufficient to study degree of mixing.
 Mixing requires low power.
SOLID MIXING:
 Flow currents are not possible.
 Product often consists of two or more easily identifiable phases.
 Large sample size is required.
 Mixing requires high power.

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APPLICATIONS:
Mixing is one of the most common pharmaceutical operations. It is involved in the
preparation of many types of formulations.
Mixing is also an intermediate stage in the production of several dosage forms.
1) Wet mixing in the granulation step in the production of tablets & capsules.
2) Dry mixing of several ingredients ready for direct compression as in tablets.
3) Dry blending of powders in capsules , dry syrups & compound powders
( insufflations).
4) Production of pellets for capsules.
INTER PARTICLE INTERACTIONS – SEGREGATION
The particle characteristics such as size , size distribution , shape & surface influence the
inter particle interactions in a powder bed.
Inertial forces:
I. Inertial forces tend to hold neighbouring particle in a fixed relative position.
II. These are van der walls , electrostatic & surface forces.
III. A special mention of surface forces is relevant.
Surface forces:
I. Poor flow properties of the powder bed inside a blender.
II. Wide different in particle sizes in a dry mixture.
III. Differences in the mobility of individual ingredients.
IV. Differences in particle density & shape to a lesser extent.
V. Transporting stage , pouring the powder from one container to another (hopper or
drums ) , or emptying the container.
VI. Dusting stage , fine particles become air borne & separate from the bulk of the
powder.

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MECHANISMS OF MIXING IN SOLIDS
Segregation of particles occurs due to a number of reasons. Mixing can prevents it. The
principle mechanisms in solid – solid mixing:
CONVECTIVE MIXING:
 It is achieved by the inversion of the powder bed using blades or paddles or screw
elements.
 A large mass of material moves from one part to another.
 Convective mixing is referred to as macro mixing.
SHEAR MIXING:
 In this type , the forces of attraction are broken down so that each particle moves on
its own between regions of different composition & parallel to their surfaces.
 In a particulate mass , the forces of attraction are predominating , which make the
layers slip over one another.
 Such types of attraction forces are predominant among same type of particles.
 Shear forces reduces these attractions & reduce the scale of segregation.
DIFFUSIVE MIXING:
 It involves the random motion of particles within the powder bed , there by particles
changes their positions relative to one another.
 Diffusive mixing occurs at the interfaces of dissimilar regions.
 Diffusion is sometimes referred to as micro mixing.
MIXING PROCESS – STEPS
In the solid – solid mixing operation four steps involved
1. Expansion of the bed of solids.
2. Application of three – dimensional shear forces to the powder bed.
3. Mix long enough to permit true randomization of particles.
4. Maintain randomization ( no segregation after mixing ).
Mixing is expected to produce random distribution of particles. It depends on the
probability that an event happens in a given time. The law of mixing appears to follow a
first order.

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M = A ( I – e-kt )
Where as ,
M= degree of mixing after time .
t = time , min
A and k =constants
DEGREE OF MIXING AND
STATISTICAL EVALUATION
 Degree of mixing is also known as degree of homogeneity.
 The degree of mixing must be considered for the purpose of economics.
 Time of mixing should be long enough to obtain an acceptable randomization.
IDEAL MIXING OR PERFECT MIXING:
 As illustrated by equation (1) , the mixing process will never yield an ideal or perfect
mixing.
1 2
1 = perfect mix
2 = random mix

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ACCEPTABLE MIXING :
 Since perfect mixing can not be achieved , other alternatives for obtained an
acceptable mix must be considered.
1. Random mixing
2. Ordered mixing
RANDOM MIXING :
 It is indicated by random distribution of particles.
 Random mixing means same ratio of components in the entire mixture.
 Instead number of propertie4s of the powders being mixed influence this approach
to randomness.
ORDERED MIXING :
 Ordered mixing is described as the use of mechanical , adhesion & coating forces.
 Ordered units in the mix should be such that ordered unit will be the smallest
possible sample to the mix.
 Ordered mixing probably yield the closest situation of the perfect mix.
 This can be achieved by a number of ways .
1. Mechanical means of ordered mixing
2. Adhesion means of ordered mixing
3. Coating means of order mixing.
MECHANICAL MEANS OF ORDERED MIXING :
The mass of each ingredient is divided & re4combined a number of times in the powdered
bed.
The smaller the units , the more uniform the mix.
Since no particulate adhesion is present , segregation of the mix easily takes place on
further handling.

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ADHESION MEANS OF ORDERED MIXING:
 These forces of particles may create ordered units of nearly identical
composition depending on the process.
 Partial solubilisation or the use of a binding agent during wet granulation
approximates the same effects .
COATING MEANS OF ORDERED MIXING :
 Particles in an assemblage may also be coated with other ingredients to give
an ordered mix either as individual or coated particle agglomerates.

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adhesion
solubilization
coating
coating
particle
ordered – unit
. single coated particle
STATISTICAL PARAMETERS:
ARITHMETRIC MEAN:
The mean ( assay value or size distribution analysis ) value of a group of random samples is
a measure of the central tendency of the batch population.
The arithmetic mean is expressed as:
Arithmetic mean 𝑦
̅ =∑
𝑛
𝑖
𝑦𝑖
𝑛
taking a number of samples ( n ) , the true mean 𝑦
̅ , is estimated . mean may be attributed
to concentration of a component or partical size of a particular component.

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STANDARD DEVIATION:
The spread of individual samples is important , because it is impracticable to obtain the
same true mean for the same product mix obtained by another lot or by another mixer.
Therefore , standard deviation is used. It is expressed as :
Standard deviation , σ =
√∑
𝑛
𝑖
( 𝑦𝑖−𝑦
̅
( 𝑛−1)
RELATIVE STANDARD DEVIATION :
One way follows the mixing operation in a given process by plotting the standard
deviations as a function of time.
The relative standard deviation ( RSD ) should replace the standard deviation as a measure
of sample uniformity , which is expressed as :
Percent relative standard deviation (RSD) =
𝑆𝑇𝐴𝑁𝐷𝐴𝑅𝐷 𝐷𝐸𝑉𝐼𝐴𝑇𝐼𝑂𝑁 ( 𝜎 )
𝑀𝐸𝐴𝑁 ( 𝑌 )
× 100
MIXING INDICES :
The selection of a mixer depends on the mixing index or degree of mixing.
The above mentioned statistical parameters are useful for evaluating the mixing indices.
Mixing index involves the comparison of standard deviation of sample of a mixture under
study with the estimated standard deviation of a completely random mixture.
Mixing index is expressed by lacey . two of them are :
Mixing index , M =
𝑆𝑇𝐴𝑁𝐷𝐴𝑅𝐷 𝐷𝐸𝑉𝐼𝐴𝑇𝐼𝑂𝑁 𝑂𝐹 𝑅𝐴𝑁𝐷𝑂𝑀 𝐵𝐿𝐸𝑁𝐷
𝑆𝑇𝐴𝑁𝐷𝐴𝑅𝐷 𝐷𝐸𝑉𝐼𝐴𝑇𝐼𝑂𝑁 𝑂𝐹 𝑇𝐻𝐸 𝑆𝐴𝑀𝑃𝐿𝐸 𝐵𝐿𝐸𝑁𝐷𝑆
=
𝜎𝑅
𝜎

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Mixture index , M =
𝜎𝑜− 𝜎
𝜎𝑜− 𝜎𝑅
Where as ,
σ0 = standard deviation of unmixed powders
before mixing has begum , the material in the mixer exists in two layers , one of which
contains no tracer material & one of which is tracer only .
under these conditions , the standard deviation at zero time (σ0) may be expressed as :
σ0 = √𝛼 ( 1 − 𝛼)
where as
α = over all fraction of tracer in the mixture.
FACTORS INFLUENCING MIXING
 Particle and powder characteristics the mixing process.
 Aggregation inhibits proper mixing.
 Therefore , higher shearing forces are applied.
 Hence , correct mixing of one component does not imply good mixing of other
components.
 Therefore , adding dye to the mixture is often misleading.
 The dye may not aggregate , but active substance may aggregate.
 A single factor can in no way be considered as a unique indication of mixing.
 However , flow properties of the components is the most important consideration
which is again influenced by a number of factors.
NATURE OF THE SURFACE :
 Rough surface of the components does not induce satisfactory mixing.
 This can be due to the entry of active substance into pores of the other
ingredients.

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 Adding a substance , which will be adsorbed on its surface , can decrease
aggregation.
 Example is the addition of aerosol ( colloidal silicon oxide ) .
 Thus, a strongly aggregating zinc oxide becomes a fine dusting powder , which
can be mixed easily.
DENSITY OF THE PARTICLES :
 It is of minor importance.
 Demixing is accelerated when the density of the smaller particles is higher
or when the mixing process is stopped abruptly.
 This is due to the fact that dense material always moves downward & settles
at the bottom.
PARTICLE SIZE :
 It is easy to mix two powders having approximately the same particle size.
 The variation of particle size can lead to separation , because the small
particles move down word through the spaces between the bigger particles.
 As the particle size increases , flow properties also increase due to the
influence of gravitational force on the size.
 Beyond a particular point , flow property decrease.
 The powders with a mean particles size of less than 100 micro meter are free
flowing , which facilitates mixing.
PARTICAL SHAPE :
 The ideal particle is spherical in shape for the purpose of uniform mixing.
 The irregular shapes can become inter locked & there are less chances of
separation of particles once these are mixed together.
PARTICLE CHARGE:
 Some particles exert attractive forces due to electrostatic charge on them.
 This can lead to separation or segregation.

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PROPORTION OF MATERIALS :
 The best results can be obtained if two powders are mixed in equal proportion by
volume.
 If there is a large different in the proportion of two powders , mixing is always
done in the ascending order of their weights.
 The fundamental aspects of the particles and powders are discussed in the
pharmaceuticals.
CLASSIFICATION OF EQUIPMENT FOR
SOLIDS MIXING
S.NO NATURE OF
MIXER
EXAMPLES MECHANISM OF
MIXING
1 Batch type small
scale
Mortar and pestle trituration
2 Tumbling mixers or
cylindrical mixers
with out mixing
blade
Double cone blender , V cone
mixers with out baffles cube
blender
Tumbling action
3 Tumbling mixer with
a mixing blade
V cone blender with a mixing
blade double cone blender with
a mixing blade
Tumbling action as well as
shearing with blade
4 Static mixers Ribbon blender sigma blender
planetary
Stationary shell and
rotating blade
5 Air mixer or
fluidized mixers
Fluidized mixer Air supported blending
6 Continuous type
large scale
Barrel type , zigzag type Rotating shell with rotating
blade

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Free flowing solids = V cone blender
Double cone blender
Cohesive solids = planetary mixer
Sigma blender
EQUIPMENT
 A mixture that promotes the randomness in mixing should be selected.
 It should also prevent the conditions responsible for segregation.
 Therefore , optimization of operational conditions is critical.
MIXING EQUIPMENT – CRITERIA :
o The powder bed may expand sufficiently , therefore , equipment should never be
filled for more than about 60% so as to leave sufficient mixing volume.
o The particles should be subjected to movement in three directions.
o The shearing force should be sufficient to prevent aggregation.
o Appropriate mixing mechanism should be selected and allowed to continue for
optimum time.
o There should be no centrifugal effect , so that the powder does not get separated
according to their weights.
o The forces should not cause breakage of the particles , which may bring about
demixing due to differences in particle size.
o The mixing process should be stopped , because slow or diminishing forces in one
direction might cause demixing.
o Therefore handling of powder blend after mixing is equally important.

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TUMBLERS OR CYLINDRICAL BLENDERS
WITH NO MIXING BLADE
 This is a general class of equipment meant for blending of dry powders.
 The equipment consists of a container of one of the several geometric form.
 Cubes or hexagonal cylinders may be rotated in any axis depending on the
manufacture.
 Such a cylinders vessel is not suitable for mixing since one – dimensional
movement would be obtained.
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( A ) CYLINDRICAL BLENDER ( B ) CUBE BLENDER
 Slow rotation – no intense tumbling , no cascade motion . not enough shear rates is
applied.
 Rapid rotation – sufficient centrifugal action to hold the powder to the sides of the
mixer , more dusting & segregation of fines is possible.
TWIN SHELL BLENDER OR V CONE BLENDER

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v Cone blender , rotating shell with out baffles.
1. The construction of a twin shell blender .
2. It is made of either stainless steel or transparent plastic.
3. Smaller models take a charge of 20kg & rotate 35 revolutions per min , while larger
ones take a charge of about 1 ton & rotate at 15 revolutions per min.
4. The material is loads through either of the shell hatches.
5. The material ( to be blender ) is loaded approximately 50 to 60 % of the total
volume.
6. The powder mass is converted shock wise , so that no demixing due to density
differences will occurs.
7.At high speeds , more dusting or segregation of fines is possible , while at low
speeds , not enough shear may be applied.
ADVANTAGES :
1. If fragile granules are to be blended , twin shell blender is suitable because of
minimum attrition.
2. They handle large capacities.
3. Easy to clean , load & unload .
4. This equipment requires minimum maintenance.
DISADVANTAGES :
1.Twin shell blender needs high headspace for installation.
2.It is not suitable for fine particulate system or ingredients of large differences in the
particle size distribution , because not enough shear is applied.
3.If powders are free flowing , serial dilution is required for the addition of low dose
active ingredient.

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DOUBLE CONE BLENDER
1. The construction of a double cone blender is it is usually charged & discharged
through the same port.
2. It is an efficient design for mixing powders of different densities.
3. These are used mostly for small amounts of powders.
4. The rate of rotation should be optimum depending on the size & shape of the
tumbler , nature of material to be mixed.
5. Commonly the range is 30 to 100 revolution per minute.
6. The method remains same as that of the V – cone blender.
7. The advantage & disadvantage for double cone blender are same as given in twin
shell blender or V- cone blender.

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TUMBLING BLENDERS WITH AGITATOR
MIXING BLADE
V cone blender. Rotating shell with rotating baffles.
Advantages :
1. Baffles are useful for both wet & dry mixing.
2. Wide range of shearing force can be applied with agitator
bars permitting the intimate mixing of very fine as well as coarse
powders.
3. Serial dilution is not needed when incorporating low-dose
active ingredient.

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DISADVANTAGES :
1. Attrition is large , size reduction of friable particles result.
2. Scale-up can prove a problem , because general principles of scale up do not
work.
3. Cleaning may be a problem , because the agitator assembly must be removed
& the packing should be replaced for a product change over.
4. Potential packing ( sealing ) problems.
RIBBON BLENDER
RIBBON MIXER . STATIONARY SHELL & ROTATING BLANDER
PRINCIPLE :
1. The mechanism of mixing is shear.
2. Shear is transferred to the powder bed by moving blades ( ribbon shaped ) in a fixed
( non – movable ) shell.
3. High shear rates are effective in breaking lumps & aggregates.
4. Convective mixing also occurs as the powders bed is lifted & allowed to cascade to
the bottom of the container.
5. An equilibrium state of mixing can be achieved.

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Construction :
1. The construction of a ribbon blender it consists of a non – movable
horizontal cylindrical trough ( shell ) usually open at top .
2. It is fitted with two helical blades , which are mounted on the same shaft
through the long axis of the trough.
3. The blades have both right & left hand twists.
4. The blades are connected to a fixed speed drive.
5. Ribbon blender is top loading with a bottom discharge port.
6. The trough can be closed with a lid
.

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WORKING :
1. Through the fixed speed drive , ribbons are allowed to rotate.
2. One blade moves the solids slowly in one direction & the other moves them
quickly in opposite direction .
3. Different powders are introduced from the top of the trough.
4. The body is covered because considerable dust may be evolved during dry
blending & granulating solution may evaporate during wet granulation.
5. The powder are lifted by a centrally located vertical screw & allowed to cascade to
the bottom of the container ( tumbling action ).
6. The counteracting blades set up high shear & are effective in breaking up lumps or
aggregates.
7. Helical blades move the powders from one end to another as shown in diagram.
8. The final stage of mix represents an equilibrium state.
9. The operating conditions of a given mixer can markedly effect the study & thus the
quality of the mixing.
10. The blend is discharged from the bottom opening.

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USES :
1. Ribbon blender is used to mix finely divided solids , wet solid mass , sticky & plastic
solids.
2. Uniform size & density material can be easily mixed.
3. It is used for liquid – liquid & solid – solid
.
ADVANTAGES :
1. High shear can be applied by using perforated baffles , which bring about a
rubbing & break down aggregates.
2. Headroom requirement is less.
DISADVANTAGES :
1. It is a poor mixer , because movement of particles is two – dimensional.
2. Shearing action is less than is planetary mixer.
3. Dead spots ( areas that remain unmixed ) are observed in the mixer , though
they are minimum.
4. It is having fixed speed drive.

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SIGMA BLADE MIXER
PRINCIPLE :
 The mechanical of mixing is shearing.
 The inter – meshing of sigma shaped blades creates high shear and kneading
actions.
 Convective mixing is achieved by cascading the material.
CONSTRUCTION :
 It consists of double trough shaped stationary bowl , two sigma ( indicates the shape
of the greek letter ) shaped blades are fitted horizontally in each trough of the bowl ,
these are connected to a fixed speed drive.
 The mixer is loaded from the top & unloaded by tilting the entire bowl by means of a
rack – and – pinion drive.

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WORKING :
 Different powders are introduced from the top of the trough.
 The body is covered because considerable dust may be evolved during dry blending
& granulating solution may evaporate during wet granulation.
 Through the fixed speed drive , the sigma blades are allowed to rotate.
 The blades move at different speeds , one usually about twice the speed of other ,
resulting in lateral pulling of the material.
 They turn towards each other so that the powders move from the sides to the centre
of the bowl.
 The material further moves from the top to downwards over the point & then
sheared between the blades & the wall of the trough.
 Thus cascading action ( convective ) as wall as shear action can be achieved.
 The perforated blades help in breaking lumps & aggregates.
 Thus high shear forces are set up.
 The final stage of mix represents an equilibrium state.
 The operating conditions of a given mixer can markedly effect the steady state &
thus the quality of the mixing.
 By means of a rack – and – pinion drive the bowl is tilted to empty the blend.
USES :
 Sigma blade mixer is commonly used for mixing of dough ingredients in the baking
industry.
 It is used in wet granulation process in the manufacture of tablets , pill masses &
ointments.
 It is primarily used for liquid – solid mixing , although it can be used for solid – solid mixing.
ADVANTAGES :
 Sigma blade mixer creates a minimum dead space during mixing.
 It has close tolerances between the blades & the side – walls as well as bottom of the
mixer shall.

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DISADVANTAGES :
 Sigma blade mixer works at a fixed speed.
PLANETARY MIXER
PRINCIPLE :
 In a planetary , mixer , the blade tears the mass apart & shear is applied between a
moving blade & a stationary wall.
 The mixing arm moves in two ways , around its own axis & around the central axis ,
so that it reaches every spot of the vessel.
 The plates in the blade are sloped so that the powder makes an upward movement.
 Therefore , tumbling ( convective ) motion is also obtained.
CONSTRUCTION :
 The construction of a planetary mixer is shown in.
 It consists of a vertical cylindrical shell , which can be removed either by lowering it
beneath the blade or raising the blade above the bowl.
 It rotates around the ring gear , which further rotates round the mixer blade.
 It is normally built with a variable speed drive.

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WORKING :
 In the planetary mixer , the agitator has a planetary motion.
 It rotates on its own & around the central axis so that it reaches all parts of the vessel.
 Beater is shaped to pass with close clearance over the side & bottom of the mixing bowl.
 Therefore , literally there are no dead spaces in the mixing bowl.
 The blade tears the mass apart & shear is applied between the moving blade & the
stationary wall.
 The plates in the blade are sloped so that the powder makes an upward movement.
 Therefore , tumbling ( convective ) motion is also obtained.
 Since it is a variable speed driven , initially the blade moves slowly for premixing &
finally at increased speed for active mixing.
 Thus high shear can be applied for mixing.
 Emptying the bowl may be done by dumping mechanism.
USES:
 Planetary mixer produces precise blends in addition to breaking down for of
agglomerates rapidly.
 Low speeds are used for dry blending & faster speeds for the kneading action required
in wet granulation.
 Steam jacketed bowls are used in the manufacture of sustained release products &
ointments.
ADVANTAGES :
 Speed of the rotation can be varied at will , so it is advantageous over sigma blade or
ribbon type blenders.
 This is more useful for wet granulation process.
 There are no packing glands in contact with the product.
DISADVANTAGES :
 Mechanical heat is built up with in the power mix.
 It required high power.
 It has limited size and is useful for batch work only

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AIR MIXER OR FLUDIZED MIXER
PRINCIPLE :
The air movement is used for mixing powders.
The powders are mixed in a stationary cylindrical vessel.
Air is admitted at its base at an angle.
This gives tumbling action spiral movements to the powder.
Thus mixing is achieved.
The construction & working of an air mixer or fluidized mixer remains same as
shown in fluidized bed dryer in the chapter drying.
ADVANTAGES :
 Air mixer shortens the mixing time.
 It is useful as a through – output.
 Mixing is intimate & effcient .
 It is also used for wet granulation in tablets.
 With additional attachments , this equipment is useful for mixing , wet massing & drying
in the wet massing & drying in the wet granulation method.
 This method is also used for coating with some modifications.

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BARREL TYPE CONTINUOUS MIXER
PRINCIPLE :
 In the barrel type continuous mixer , the rotating shell keeps the material under
tumbling motion.
 The presences of baffles further enhances the mixer action.
 When the material approach the mid – point of the shall , another set of baffles
causes part of the material to move towards the direction of inlet end allowing the
remaining part to move forward.
 Such a mechanism provides intense mixing of ingredients.
 This process continues up to discharge & where another set of baffles guide the
discharge port.
 The blended material at an equilibrium state overflows from the discharge end.
CONSTUCTION :
 It resembles a large cement mixer.
 Baffles are fitted to the inner surface of the shall.
 The shall is fixed to a shaft , which is allowed to rotate using electric power.
 Side opening are provided on each side for chare & discharing of material.

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WORKING :
 The mixer is allowed to rotate.
 Along with it the baffles also rotate.
 The begin moving towards the opposite end of the blender due to tumbling action.
 Baffles further enhance the mixing.
 As the material approaches the mid – point of the mixer shall , the baffles are so
positioned to cause the feedback of part of the material in the direction of the inlet
end.
 The feedback action continues up to the discharge end , where another set of baffles
guides the material to the discharge port.
 The overflow of material causes the blended solid to discharge.
 Since charging & discharging are simultaneously done , the process becomes
continuous.
ZIGZAG CONTINOUS BLENDER
PRINCIPLE :
Zigzag continue blender is a rotating shall type having several V shaped blenders
connected in series.
The material undergoes tumbling motion.
When the V section is inverted , the material splits into two portions ; one – half of
material moves backward ( in to the preceding section ) , while another – half of
material moves forward.
Due to inclined axis of the shell towards the discharged end , the material gets
discharged.

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As the first V section clears the charge , fresh feed enters.
Thus , it is used for continuous blending of solid.
CONSTUCTION :
The shell takes the shape of several V shaped blenders connected in series.
A chamber for charging is attached to one end of the shell.
The other end allows the discharged of material.
The shell is inclined towards the discharge end.
WORKING :
A single pre – weighed charge is introduced into the charge chamber.
As the shell rotates , at one particular angle a metered material enters the V –
shaped section by gravity.
With each rotation , one – half of the material moves forward back to the preceding
leg & another – half of the material moves forward to the next leg of the blender.
In each rotation a part of the material moves towards the discharge end.
As the first charge clears the first V section , which may take only a few minutes, the
next charged is added.
The uniformity of blending depends on the flow properties of the ingredients.

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29
29
OTHER EQUIPMENT
1. BATCH MIXER
2. CONICAL MIXER

31. abcp |
30
30
3.BATCH MIXER DRYER & DRUM WITH
DCS – DES POWDER TRANSFER
4.STATIC MIXER

32. abcp |
31
31
5.DRUM – BLENDER
6.BATCH MIXER & TABLET PROCESS

33. abcp |
32
32
7.MIXING TANK
7. V-TYPE BLENDERS

34. abcp |
33
33
REFERENCES :
C.V.S.SUBRAHMANYAM M.pharm.,Ph.D.
THE END