11 Important Things I Learnt About High Shear Mixer Granulator

Are you new to high shear mixer granulator?

Well, in this article, you’re going to learn about some key aspects of a high shear mixer granulator. Remember, this an essential material processing machine in the food, pharmaceutical and cosmetic industries.

SaintyCo high shear mixer granulator

Whether you’re a newbie or a professional in the material processing industry, this will be a quick guide to use when sourcing for a suitable high shear granulator.

1. Key Applications of High Shear Mixer Granulators

Like most pharmaceutical equipments, this machine plays an important role in this industry. Its main purpose is mixing, granulating, humidifying, homogenizing and serving pharmaceutical materials.

Processed powder granules

Furthermore, you can use this equipment to mix both dry and wet powders. It can mix powders in a wide range of working conditions such as operating without varying pressure zones.

A high shear granulation is a perfect choice for highly cohesive material. Normally, a low shear mixer granulator machine cannot process such materials because they have a high amount of hydrophilic polymer.

2. Key Parts of High Shear Granulation Machine

The number of parts and design may vary depending on the type of machine. It is important to evaluate these parts to be sure that the machine will actually meet the various performance specifications and standards.

A section of high shear mixer granulator. Image illustrating how the chopper rotates

Here are key sections of this powder granulation equipment:

• Mixing impeller (number of blades depend on the design)
• Cylindrical mixing drum/bowl
• Multiple choppers
• Discharge port
• Motor to drive the impeller
• Spray nozzle for binding liquid
• Compressed air
• Control system

Generally, these are the basic parts if a granulation machine. Their precise design and coupling mechanism guarantees uniform and high quality granules.

3. Types of High Shear Mixer Granulator

Normally, classification these granulators depend on a range of factors. When choosing these equipment, you may consider the following options:

A section of a high shear granulation machine

• Type of dosing system

The available granulation machines may have automatic and manual systems. This may include powder and biding solution dosing system.

• Design of the impeller blade

The impeller blade determines the efficiency of the granulation process. Therefore, an equipment may have varying number of blades.

For instance, a machine may combine about 3-blade impeller. Moreover, the position and design of the impeller blades is also crucial.

In most cases, shear mixers granulator may have impeller tips located tangentially since this eliminates the possibility of dead spots.

Remember, it is the impeller will mix and spread the granulation fluid. Its speed of rotation will depend on the design and specification of the machine.

• Location or position of the impellers

You may go for either horizontal or vertical high shear mixer granulator. These two classifications depend on the position of the impeller.

But, what exactly brings this variation?

For the horizontal high shear mixer granulator, the rotation of the impellers takes place in a horizontal plane. That is, they are side driven.

On the other hand, in the vertical high shear granulators, the shaft rotates in a vertical plane. It can either be bottom or top driven.

4. Consider degree of accuracy

You need to be strict when it comes to this. Remember, in pharmaceutical material processing, accuracy is a key aspect.

First, the design should guarantee uniform granulation. If possible, the granules should be round and strong.

Granulation process

Second, the cylindrical mixing bowl or drum should process a wide range of batch sizes. This will save you the cost of buying a new equipment or the time consuming process of changing parts.

Don’t forget that this machine should allow for easy validation of the powder granulation process.

5. Regulatory Requirements

There should be a proof that the equipment adheres to a strict quality manufacturing process. For a fact, the cGMP is a crucial compliance requirement for all pharmaceutical equipment.

The cGMP regulations require that every machine should have tight mechanical seals. It should have better dust handling features while ensuring a high level of hygiene.

A tightly sealed section of the shear mixer made from aluminum

This explains why the entire structure of high shear mixer granulator is made from stainless steel.  The equipment should be made from FDA approved material while the electrical components should be CE compliant.

6. The Working Principle of High Shear Mixer Granulator

Broadly, the working principle of a high shear mixer granulator involves the following key processes. These may vary depending on the type of machine.

That is:

After switching on the granulator, it will:

• Mix the powder
• Automatically add binder (granulation liquid)
• Powder then becomes wet
• Powder crystals begin to form (nucleation)
• Densify the powder
• Attrition and breakage of granules

That is, as the powder enters the mixing chamber, it is sprayed with the liquid from the nozzle. During this time, the impellers and the hopper mixer the product forming round and strong powder granules.

7. Technology that Granulation Machine Use

High shear granulators feature a wide range of technologies. All these aim to ensure efficiency and the overall reliability of the machine.

A granulation machine with an LCD HMI

For instance, a high shear granulator may feature a fully automatic system. Siemens PLC is a perfect choice for most applications.

The machine may have an automatic discharge of compressed air seal and intelligent control system.

8. Which Factors affect the Quality of Powder granulation?

Choosing the best machine powder granulation machine is not enough. There is a wide range of factors that may influence the formation of the final granules either directly or indirectly.

These include:

• Physical and chemical properties of the powder
• Types and quantity of binder solution
• Design of granulator machine

Let me expound on the last point.

The design of the machines may have many variables and this will affect the granulation process. Some of the key aspects you need to focus on include loading process, impeller speed, chopper speed and applying granulation solution (method and rate).

9. Safety of granulation machine

Apart from the cGMP regulations, this machine comes with an overload relay protection, air pressure switch limit, proper sealing mechanism and the enclosed drive system.

All mechanical and moving parts are fully enclosed to guarantee the safety of machine users

10. Advantages of powder granulation machine

There are a number of reasons why this machine is popular most pharmaceutical processing industry. Some of the key advantages include:

• A fast powder granulation process
• Precise and accurate granule production
• Requires a small quantity of binder solution
• Short powder drying time
• A predictable production process
• Greater densification
• Reduces air pollution due to advanced dust handling properties

11. Disadvantages of powder granulation equipment

A high shear mixer has the following disadvantages:

• It may cause degradation of powder, especially for fragile or thermolabile powders
• Over wetting may cause the production of large lumps
• Produces less compressible granules
• A narrow range of operation conditions

Basically, this explains all the vital aspects of a high shear mixer.

Conclusion

From above, you can see that a high shear mixer granulator is an enclosed container with a range of blending equipment that process the powder either from below, above or sideways. The end result/output of this process is a round and compact granule.