The document discusses the functions and advantages of rotary kilns, which have been used for over 65 years in thermal processing to cause chemical reactions or physical changes in materials. Key processes include calcination, thermal desorption, organic combustion, sintering, heat setting, and reduction roasting, each serving distinct industrial needs. The company provides comprehensive services in the thermal processing industry, including custom rotary kilns and related support.

1. Rotary Kilns
Experts in process design and material
processing for over 65 years.
Processes Carried Out Using

2. Rotary kilns are an advanced thermal
processing tool used to cause a chemical
reaction or physical change in a solid
material through the application of
high temperatures.

3. Rotary kilns are extremely flexible and can be
used to process a multitude of materials.

4. Rotary kilns are extremely flexible and can be
used to process a multitude of materials.
An overview of some of the most common
processes carried out in a rotary kiln are
covered here.

5. Calcination

6. Calcination is the process of heating a
material to cause chemical dissociation
(separation).

7. Calcination is the process of heating a
material to cause chemical dissociation
(separation).
Calcination is a common process and is
frequently used in the creation of
inorganic materials, such as the
dissociation of calcium carbonate to
create calcium oxide and carbon dioxide.

8. Calcination can also be used to remove
bound moisture, such as that which is
chemically attached in Borax.

9. Thermal Desorption

10. Thermal desorption is the process of using
heat to drive off a volatile component,
such as a pesticide, from an inorganic
mineral, such as sand.

11. Thermal desorption is the process of using
heat to drive off a volatile component,
such as a pesticide, from an inorganic
mineral, such as sand.
This process is not to be confused with
incineration; instead, it is a separation
process that relies on the different
reaction temperatures of absorbent
minerals and chemicals.

12. At high temperatures, the volatile
component is vaporized, resulting in
separation without combustion.

13. At high temperatures, the volatile
component is vaporized, resulting in
separation without combustion.
An indirect kiln is most suitable for this type
of application, because the volatile
chemicals may be combustible.

14. At high temperatures, the volatile
component is vaporized, resulting in
separation without combustion.
An indirect kiln is most suitable for this type
of application, because the volatile
chemicals may be combustible.
An indirect kiln would supply the heat for
desorption, while avoiding direct contact
between the material and flame.

15. Organic
Combustion

16. Organic combustion is the thermal
treatment of organic wastes with the
intent of reducing mass and volume.

17. Organic combustion is the thermal
treatment of organic wastes with the
intent of reducing mass and volume.
This process is commonly seen in waste
treatment plants in order to reduce the
volume of organic wastes for deposit
into landfill.

18. Organic combustion leaves behind an ash
product of considerably less mass and
volume.

19. Organic combustion leaves behind an ash
product of considerably less mass and
volume.
This process is most commonly carried out
in a direct-fired kiln, because contact
between the burner flame and material
is not a concern.

20. Sintering/
Induration

21. Sintering is the process of heating a
material to just below its melting point.

22. Sintering is the process of heating a
material to just below its melting point.
This increases the strength of the material,
and is commonly seen in the proppant
industry, where material must be strong
enough to hold open rock fissures under
extreme pressures.

23. Heat Setting

24. Heat setting refers to the process of
bonding a heat resistant core mineral with
another, less heat resistant coating
material.

25. Heat setting refers to the process of
bonding a heat resistant core mineral with
another, less heat resistant coating
material.
During heat setting, the coating material is
heated to just below its liquefaction point,
at which it can evenly and more securely
coat the core material.

26. This process is commonly seen in the
roofing granule industry, where minerals
such as granite, are coated with other
materials such as colored pigments, in
order to produce a material that both
looks good and performs as needed.

27. Reduction
Roasting

28. Reduction roasting is the removal of
oxygen from a component of an ore
usually by using carbon monoxide.

29. Reduction roasting is the removal of
oxygen from a component of an ore
usually by using carbon monoxide.
The CO is typically supplied by mixing a
carbonaceous material such as coal or
coke with the ore, or by feeding it
separately.

30. A common example of this is the roasting
of a hematite-containing material to
produce magnetite that can then be
magnetically separated.

31. Conclusion
Rotary kilns are extremely flexible and can be
used to process all sorts of materials. They are
capable of carrying out a wide variety of
processes, with some of the most common
including calcination, thermal desorption,
organic combustion, sintering, heat setting,
and reduction roasting.

32. has been a leader in the thermal processing
industry since the 1950s, providing process &
product development, feasibility testing,
maintenance services, and high-quality,
custom rotary kilns.

33. Want to learn more?
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