The document discusses the processes of compaction granulation and pelletizing, highlighting their differences, advantages, and disadvantages in material processing across various industries. Compaction granulation, a dry process, offers lower operating costs but requires a higher capital investment, while pelletizing, a wet process, ensures uniform pellets but has higher operational costs due to binder use and drying. Choosing between the two methods depends on factors like material characteristics, costs, and product requirements, with feasibility testing recommended when uncertainty exists.

1. Agglomeration:
Pelletizing or
Compaction?
Experts in process design and material
processing for over 60 years.

2. The choice of whether to use
compaction granulation or pelletization
to process material fines is one
commonly seen throughout a variety
of industries.

3. The two processes are very different, with
each offering different advantages and
disadvantages. And while the material will
sometimes dictate which process must be
used, often times, both methods must be
explored to determine which method will best
suit the material and process requirements.

4. Compaction
Granulation

5. Compaction granulation is a type of pressure
agglomeration that produces dense, jagged
granules.

6. Compaction granulation is a type of pressure
agglomeration that produces dense, jagged
granules.
This is a dry process, and relies on the
principle that some materials will naturally
adhere to themselves under extreme
pressure. Not all materials will behave this
way, so compaction granulation is not
always an option.

7. This process is used to process a variety of
materials, from chemicals and fertilizers, to
minerals and clays.

8. How it Works

9. Compaction granulation is carried out in a
compactor, or double roll press.

10. Material fines are
fed between two
counter rotating
rolls. The rolls use
extreme pressure
to press the fines
into a form.

11. Material fines are
fed between two
counter rotating
rolls. The rolls use
extreme pressure
to press the fines
into a form.
This form is then
broken up into the
desired granule
size.

12. Since this process utilizes pressure, typically no
binder is needed.
Subsequently, this processing method also
does not require a drying stage in most
applications.

13. Granules are sometimes conditioned after
compaction, in order to help reduce the
opportunity for attrition.

14. This can be carried out in paddle mixer, or a
coating/conditioning drum.

15. This can be carried out in paddle mixer, or a
coating/conditioning drum.
This step can also be used to include
desirable additives, such as anti-caking
additives and the like.

16. Simplified Compaction Diagram
1. Raw Feed Materials
2. Mill
3. Surge Hopper
4. Humidificator Mixer
5. Protecting Screen
6. Compactor
7. Flake Breaker
8. Granulators
9. Screen
10. Polishing Drum
11. Screen
12. Screw for Recycles

17. Advantages

18. Lower Operating Costs
The main advantage to compaction
granulation is that it offers lower operating
costs than pelletizing. This is because a binder
is usually not needed, so there are no binder
costs, and subsequently, no drying step is
needed, so there are no costs in terms of
drying energy.

19. Disadvantages

20. Larger Capital Investment
Compaction granulation does require
a higher initial capital investment.

21. Attrition
Attrition is commonly seen with
granules produced via the
compaction process, because of the
rough, jagged edges. There are
methods to help combat attrition, but
these can increase operating costs.

22. Pelletizing

23. Pelletizing is a non-pressure (tumble growth)
agglomeration method used throughout a
variety of industries to process all sorts of
materials into uniform, round pellets.

24. How it Works

25. The pelletizing process is most often
comprised of three main steps: pre-
conditioning, pelletizing, and drying. In
many applications, the pre-conditioning
stage is optional, but offers many benefits.

26. Pelletizing is a wet process, requiring the use
of a binding agent to foster particle size
enlargement.

27. In a typical pelletizing process,
material fines are first conditioned in a
pin mixer.

28. In a typical pelletizing process,
material fines are first conditioned in a
pin mixer.
The material is then fed onto a disc
pelletizer, where the pellets are
“grown.” This is achieved by tumbling
the fines against themselves in the
presence of a binder, a process similar
to rolling a snowball.

29. Once pellets have reached the
desired size, they exit the pelletizer,
and are carried via a conveyor to a
dryer – most often a rotary dryer.

30. Once pellets have reached the
desired size, they exit the pelletizer,
and are carried via a conveyor to a
dryer – most often a rotary dryer.
Here, pellets are dried into their final
form, allowing them to withstand
further handling and transportation,
but still break down as needed.

31. Simplified Pelletizing Diagram
1. Paddle/Pin Mixer
2. Disc Pelletizer
3. Liquid Spray System
4. Transfer Conveyor
5. Rotary Dryer
6. Vibrating Screen
7. Oversize Mill
8. Surge Hopper

32. This process produces uniform, round pellets
that break down easily, but can still withstand
handling and transportation.

33. Advantages

34. Faster Nutrient Delivery
Because pellets are not created
through the use of pressure, they are less
dense than granules created in the
compaction process. Pellets are
capable of withstanding handling and
transport, but can still break down
quickly upon application.

35. Faster Nutrient Delivery
Because pellets are not created
through the use of pressure, they are less
dense than granules created in the
compaction process. Pellets are
capable of withstanding handling and
transport, but can still break down
quickly upon application.
This is particularly beneficial in
agricultural settings, such as with soil
amendments and fertilizers, as well as
other products that benefit from faster
product breakdown.

36. Less Dust & Fines
Round pellets produce significantly less
dust and fines than jagged granules.
This is because there are no rough
edges to break off, creating dust.

37. Binders as a Benefit
Though required in the pelletizing
process, binders can actually serve as
beneficial additives. This allows for tight
control of product formulation, and
can help to create a pellet product
enhanced with desirable additives.

38. Lower Capital Costs
Pelletizing operations require a lower
capital investment than compaction
granulation.

39. Disadvantages

40. Higher Processing Costs
The use of a binder, and subsequently
the required drying step, results in
higher processing costs compared to
compaction granulation.

41. Conclusion
The choice between compaction
granulation and pelletizing is one that
requires careful consideration.

42. Conclusion
The choice between compaction
granulation and pelletizing is one that
requires careful consideration.
End product use, capital costs, operating
costs, and other factors must all be
considered.

43. Sometimes, the choice between the two
methods is clear, while other times, it is not.
When it’s not clear which method will best suit
your processing needs, testing your material in
a feasibility lab can also help to determine
which method will produce the desired results.

44. has been a leader in the agglomeration industry
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