Rotary kiln

Basic function:

Wet rotary kiln should have the following basic functions in order to calcinate good cement clinker and reduce coal consumption.
1. Inject pulverized coal to kiln with the dispersed shape and a certain speed. Try to strengthen coal and air mixing.
2. Strengthen air disturbance and increase air diffusion speed in order to blow away Volatile gas membrane around pulverized coal particle and enlarge the contact of fixed carbon and secondary air.
3. Add right amount of fresh air and solve the problem of hypoxia in the flame center.
4. Low primary air consumption and improve the heat recovery efficiency of clinker.
5. Adapt to feeding material change, flame shape and length quickly. It should be easy to control and adjust the position of flame.
6. Strong adaptability toward combustion quality.
7. Wet rotary kiln environmental temperature is very high and rotary kiln nozzle has high temperature resistance. Effective high temperature resistance measures should be done to prevent nozzle from being burned.

Composition:

1. Cylinder and kiln lining: Cylinder, rolled by steel plate, is the container for the completion of physical and chemical changes. So it is the body of rotary kiln. Kiln material temperature is up to 1450℃, so cylinder body has masonry refractory material to protect cylinder and reduce heat dissipation. According to the process of material change, cylinder is divided into various working zones, such as drying zone, preheating zone, decomposition zone, firing zone and cooling zone.
2. Heat exchanger: To enhance the effect of heat transfer, the cylinder body often also has a variety of types of chain to make up heat exchange devices.
3. Wheel belt: cylinder, kiln lining, material and all rotary kiln weight comes to support device through wheel belt.
4. Support device: It consist a pair of roller bearings and a big base plate. A pair of roller supports a wheel belt to allow cylinder to move freely and convey huge load to the basic. Support device has generally 2-7 blocks. It is equipped with retainer wheel on a certain block or several blocks, which is called support device with retainer wheel. Its role is to limit or control the rotary kiln section of axial movement.
5. Drive device: gear ring is equipped in the middle cylinder and fixed in the cylinder by spring plate. It drives through gear wheel to make cylinder rotate. At the same time, in order to adapt to operation and maintenance needs, large rotary kiln is equipped with auxiliary drive to make kiln drive with a very low speed.
6. Kiln hood: it is intermediate which connects kiln head and middle process equipment and it is the zone for looking at the operation of fire. Therefore kiln hood is equipped with fire hole and access door.
7. Burner: Rotary burner injects through cylinder rotary head and heat material by frame radiation to the desired temperature. Burner consist coal burner, gun oil, gas nozzle and so on.
8. Cold smoke chamber: it is intermediate of connecting kiln end and material feeding equipment. Smoke comes into smoke flue and dust collecting system through cool smoke chamber. Feed material directly to kiln end from feeding device.
9. Feeding device: it is accessory equipment for rotary kiln. Feeding should be stable, uniform and easy to control so that it can cooperate with the operation of kiln.