What industries use rotary kilns?
The indirect rotary kiln is a prominent application in these and other industries:
- Cement.
- Infrastructure.
- Building Materials.
- Lime/Limestone.
- Gypsum.
- Process Metallurgy.
- Food Processing.
- Pharmaceuticals.
Where is rotary kiln used for?
A rotary kiln is a physically large process unit used in cement production where limestone is decomposed into calcium oxide which forms the basis of cement clinker particles under high temperatures.
Is a calciner a kiln?
Even today the most common “calciner” is a lime kiln where limestone is heated, driving off carbon dioxide to produce calcium oxide – “lime”. Apart from lime and cement manufacture calciners are also used for processing bauxite, gypsum and petroleum coke.
What are the main parts of rotary kiln?
The basic components of a rotary kiln are the shell, the refractory lining, support tyres (riding rings) and rollers, drive gear and internal heat exchangers.
What are kilns made of?
Electric ceramic kilns are very simple structures. They are essentially closed boxes made from soft, porous, highly insulating bricks. Inside the electric kiln, running along channels grooved into its walls, are coils made from a special alloy.
What is the purpose of kiln?
A kiln is a thermally insulated chamber, a type of oven, that produces temperatures sufficient to complete some process, such as hardening, drying, or chemical changes. Kilns have been used for millennia to turn objects made from clay into pottery, tiles and bricks.
How does a calciner work?
The heat source for a calciner is either electric resistive wires or fuel-fired burners. The heat source heats the surface of the cylinder. In turn, the cylinder heats up the material by radiant heat transfer, indirect heat transfer, and direct contact of the product and the hot surface of the cylinder.
What is the length of rotary kiln?
Rotary kiln is basically a cylinder of length 50 – 120 m (modern kilns) and 3.5 to 6.5 feet in diameter. During kiln mainly on how long it takes until the temperature of the raw material clinker temperature of about 1370˚C is, it depends.
How many types of kilns are there?
In the broadest terms, there are two types of kilns: intermittent and continuous, both being an insulated box with a controlled inner temperature and atmosphere. A continuous kiln, sometimes called a tunnel kiln, is long with only the central portion directly heated.
What are rotary calciners used for?
Rotary calciners, also commonly called indirect kilns, are used in various calcination operations where exhaust gases must be minimized, when processing finely divided solids, or where temperature must be tightly controlled along the length of the kiln. A calciner is comprised of a rotating drum inside a furnace, which is externally heated.
What is a calciner kiln?
Unlike direct-fired kilns, which utilize direct contact between the material and process gas to carry out processing, in a calciner, heat is transferred from the shell of the externally heated kiln to the bed of material through radiation.
What are the different types of rotary kiln?
Rotary kiln can be divided into cement kiln, metallurgical chemical kiln and lime kiln according to different processing materials.
What are the components of a direct-fired calciner?
The batch and pilot direct-fired equipment can be configured to include the following: combustion chamber, afterburner, baghouse, quench chamber, and wet scrubber. The image below shows the standard components of a calciner. Click image to view larger. Rotary Kiln Resource Rec…