Rotary dryers are an integral component throughout the processing of phosphate rock into phosphatic fertilizers and animal feed products. This presentation goes over how rotary dryers are used in the phosphates industry, the benefits they can offer, and factors to consider during the phosphate dryer design stage.

1. Phosphates Processing
Experts in process design and material
processing for over 65 years.
Rotary Dryers in

2. Phosphorus is essential to all life on Earth. Its
life-giving properties are key to a variety of
cellular and biological processes that allow
plants, animals, and even humans to grow
strong and healthy.

3. For this reason, phosphate rock is processed
into a variety of products, namely, animal
feeds and fertilizers.

4. For this reason, phosphate rock is processed
into a variety of products, namely, animal
feeds and fertilizers.
Despite variation in end use, however, one
tool helps to make the phosphate products
that keep our world running possible:
the rotary dryer.

5. FEECO Rotary Dryer

6. There are three areas where rotary dryers
are a key tool in processing:

7. There are three areas where rotary dryers
are a key tool in processing:
• Drying phosphate rock

8. There are three areas where rotary dryers
are a key tool in processing:
• Drying phosphate rock
• Drying fertilizer products

9. There are three areas where rotary dryers
are a key tool in processing:
• Drying phosphate rock
• Drying fertilizer products
• Drying animal feed products

10. Drying Phosphate Rock
While the beneficiation of phosphate
rock differs greatly depending on the
deposit, in general, phosphate rock is
processed via a wet process, resulting in
a material that must be dried before it
can move on to any subsequent
processing.

11. And while this is a necessary part of the
process, it does offer benefits as well:

12. And while this is a necessary part of the
process, it does offer benefits as well:
Improved Product Handling: Handling
issues associated with wet or sticky
phosphate rock are avoided.

13. And while this is a necessary part of the
process, it does offer benefits as well:
Improved Product Handling: Handling
issues associated with wet or sticky
phosphate rock are avoided.
Reduced Potential for Buildup: Drying
decreases the potential for material to
build up, thereby improving process
flow and efficiency, and helping to
prevent clogged equipment.

14. Drying Phosphatic Fertilizers
Drying also is a key component in the
production of phosphatic fertilizers.

15. Drying Phosphatic Fertilizers
Drying also is a key component in the
production of phosphatic fertilizers.
Phosphatic fertilizers must be dried
before they can move on to bagging,
storage, or shipping. This not only creates
a product that can maintain its integrity,
but it also helps to reduce caking issues.

16. Drying Animal Feeds
Much like fertilizers, drying also plays a
key role in animal feed production.

17. Drying Animal Feeds
Much like fertilizers, drying also plays a
key role in animal feed production.
Again, this not only creates a product
that can maintain its integrity, but it also
helps to reduce the opportunity for
caking issues to occur.

18. The drying of granular products like those
mentioned here offers two major benefits…

19. Enhanced Product Quality: Granule
characteristics are improved through
drying in a rotary dryer. The tumbling
action further rounds and polishes the
pellets, creating a premium product,
and reducing the potential for attrition
to occur.

20. Hardened Granule Surface: Drying cures
granular products into their final form –
a hardened product that is capable of
withstanding handling, transportation,
and application.

21. Hardened Granule Surface: Drying cures
granular products into their final form –
a hardened product that is capable of
withstanding handling, transportation,
and application.
Again, this also helps to reduce caking.

22. How Phosphate Dryers
Work

23. Rotary dryers work by tumbling the material
in a rotating drum in the presence of a
drying air.

24. Rotary dryers work by tumbling the material
in a rotating drum in the presence of a
drying air.
Flights, or material lifters pick up the material
and drop it through the air stream to
maximize heat transfer.

25. These dryers are typically of the
co-current configuration, meaning the
material and air stream flow in the same
direction.

26. These dryers are typically of the
co-current configuration, meaning the
material and air stream flow in the same
direction.
When drying a granular product, this
helps to prevent the most dry material
from becoming too hot, which would
result in excess fines and attrition.

27. When drying phosphate rock, this serves
to “flash off” initial surface moisture,
allowing the rock to be dried through to
the core as it moves down the length of
the drum.

28. Advantages of the
Rotary Dryer

29. Rotary dryers are the dryer of choice
throughout the phosphates industry for
many reasons…

30. Heavy-Duty Build
Rotary dryers are robust in design and
construction, making them ideal for the
rigors of processing phosphates.

31. Heavy-Duty Build
Rotary dryers are robust in design and
construction, making them ideal for the
rigors of processing phosphates.
High Capacities
Rotary dryers are valued for their high
through-put, also ideal for processing
phosphates.

32. Uniform Results
Rotary dryers are valued for their ability
to accept variance in feedstock and
turn out a uniform product.

33. Uniform Results
Rotary dryers are valued for their ability
to accept variance in feedstock and
turn out a uniform product.
This is especially valuable at phosphate
mining and beneficiation sites, where
variance in makeup and moisture
content is often a given.

34. Material Considerations
in Drying

35. Phosphates can be a challenging material
to work with, presenting a number of
characteristics that will need to be taken
into consideration during the design and
development stages of an industrial drying
system.

36. Buildup
Phosphates can tend to clump and
buildup in dryers.

37. Buildup
Phosphates can tend to clump and
buildup in dryers.
For this reason, knocking systems are
often employed to dislodge buildup in
the drum. The ball and tube type
knocker is the most common choice.

38. A screw conveyor can also be an
option. Screw conveyors “fling” material
into the dryer, helping to break up
clumps as the material enters the dryer.

39. A screw conveyor can also be an
option. Screw conveyors “fling” material
into the dryer, helping to break up
clumps as the material enters the dryer.
Additionally, materials of construction
(such as stainless steel with a 2B finish)
can be used to help prevent buildup.

40. Abrasion
Phosphates can also be abrasive in
some forms.

41. Abrasion
Phosphates can also be abrasive in
some forms.
For this reason, materials of construction
should be carefully chosen. High-wear
areas (such as the material inlet) may
require additional modifications.

42. Dusting
Phosphates can also be dusty. This is
especially problematic when drying
phosphate rock.

43. Dusting
Phosphates can also be dusty. This is
especially problematic when drying
phosphate rock.
Here, dust is collected in a baghouse as
part of the emissions control system.

44. Dusting
Phosphates can also be dusty. This is
especially problematic when drying
phosphate rock.
Here, dust is collected in a baghouse as
part of the emissions control system.
Opportunity does exist in agglomerating
phosphate rock fines so they can be
more easily reintroduced to the process.

45. Conclusion
Rotary dryers are an integral component in
the phosphates industry, helping to produce
the many phosphate products our world
relies on.

46. Conclusion
Rotary dryers are an integral component in
the phosphates industry, helping to produce
the many phosphate products our world
relies on.
Their heavy-duty design, high capacities,
and ability to accept variance in feedstock
make them ideal for processing phosphates
of all kinds.

47. And while phosphates can present
challenges, a rotary dryer designed around
the unique characteristics of phosphates will
produce the best results.

48. has been working with phosphates for over 65
years, providing testing services, process
design and development, and custom
phosphate processing equipment.

49. Want to learn more?
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Phosphates Processing
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