What Is Rotary Kiln
Rotary kilns refer to rotary calcining kilns (sometimes called rotary furnaces). It is a pyroprocessing device used to heat materials to high temperatures in a continuous process. The kiln body is a cylinder vessel with a certain degree of tilt to the horizontal level. Raw materials are fed into the vessel from the upper end and moved to the lower end, being stirred and mixed relying on the inclination and rotation of the kiln. The kiln burner produces a lot of heat by burning fuel. This kind of heat is usually transferred to materials through flame radiation, hot gas convection, kiln brick conduction, etc., which causes the chemical reaction between raw materials and finally forms clinker.
Rotary kilns can be divided into cement kiln, metallurgical and chemical rotary kiln, lime rotary kiln and so on. Cement kilns are used for calcining cement clinker in the cement plant, which can be divided into dry cement kiln and wet cement kiln. Metallurgical and chemical rotary kilns are mainly applied in the metallurgical industry. As for the lime rotary kiln, it is the main equipment for calcining active lime and light burned dolomite used in iron and steel plants, ferroalloy plants, calcium carbide plants, and magnesium metal plants.
How Rotary Kilns Work
The rotary kiln is mainly composed of cylinder, supporting device, drive gear, refractory lining, catch-wheel device, kiln head sealing device, kiln tail sealing device, kiln hood, and other components. On the cylinder, there is a large gear ring fixed with a spring plate near the kiln tail, some pinions below are engaged with it, jointly forming the drive gear. In normal operation, the main drive motor will transfer power to this gear device through reducer to run rotary kiln. The raw material usually enters the rotary kiln from the upper end and move slowly to another end along with the chamber as it rotates. In this process, raw materials will be heated by high temperature and then decompose and produce chemical reactions so that their state finally changed. Under normal conditions, the heat source of indirect fired rotary kilns is supplied from the kiln burner outside the kiln. This kind of way protects the integrity of raw materials, while the heat source of the direct-fired rotary kiln is inside the kiln. Besides, the rotation speed and temperature of the cylinder are tightly controlled and changed according to different desire processes and material applications. After the calcination is completed, the clinker will be pre-cooled in the chamber and then be sent into the cooler for further cooling.
Rotary Kiln Diagram
- Decades of experience with the rotary kiln production and material development.
- Full automatic operation and instrument control.
- Suitable for a variety of production environments.
- Continuous monitoring of the equipment operation and product quality.
- High production efficiency and quality.