Publish Time: 2022-05-20 Origin: Site
We only introduce and analyze the wet rotary kiln process. Wet rotary kiln is usually long (length diameter ratio is 30 ~ 40). In order to increase the heat transfer area of the kiln, chains are often hung at the kiln tail to accelerate water evaporation. During the production of wet rotary kiln, water is added into the raw material mill to make the raw material into slurry with water content of 30% ~ 40%. After homogenization, the slurry meeting the requirements is sent to the kiln by the kiln head feeder to be calcined into clinker. The clinker out of the kiln is cooled by the cooler and sent to the clinker silo. The raw coal is dried and pulverized into coal powder, and then burned to supply the heat required for clinker calcination.
The characteristics of wet rotary kiln calcination are: because the raw material is made into slurry, it has strong adaptability to heterogeneous raw materials, uniform raw material composition, stable process, high clinker quality, high clinker strength grade, less dust in the grinding process and less fly ash at the kiln tail. However, the evaporation of 30% ~ 40% slurry water in wet production requires large heat consumption, and the energy consumption accounts for 1 / 2 ~ 1 / 3 of the cement cost, which is higher than that of shaft kiln and dry rotary kiln. Due to high heat consumption, large energy consumption, large water consumption and water resources consumption in wet production, wet cement production has been listed as a restricted and eliminated kiln in China.
1. The equipment of ceramsite rotary kiln is composed of rotary cylinder, supporting device, supporting device with retaining wheel, sealing device at kiln head and kiln tail, coal injection pipe device, etc.
2. The kiln body has a certain slope with the horizontal. The whole kiln body is supported by the supporting wheel device, and there is a wheel blocking device to control the up and down movement of the kiln body.
3. In addition to the main drive, the transmission part is also provided with an auxiliary drive device to ensure that the kiln body can rotate slowly and prevent the deformation of the kiln body when the main drive power supply is interrupted. The head of Hengchang kiln adopts shell and cover sealing, and the kiln tail is equipped with axial contact sealing device to ensure the reliability of sealing.
4. When the working temperature reaches (950 ℃ ~ 1050 ℃), the ultra-fine kaolin is calcined and the ceramsite sand is operated, and then the temperature is adjusted according to the number of materials, so as to finally achieve the desired goal. This calcination technology has been proved by practice that the energy consumption is low, the product is dewatered, decarburized and whitened, and the performance stability is good.
There are two types of shaft kilns used in China: ordinary shaft kiln and mechanical shaft kiln.
Ordinary shaft kiln is manual feeding and manual unloading or mechanical feeding and manual unloading; Mechanical shaft kiln is used for mechanical feeding and mechanical unloading. Mechanical shaft kiln is operated continuously, and its production, quality and labor productivity are higher than ordinary shaft kiln. According to the technical policy requirements of building materials, mechanized shaft kilns are used in small cement plants to gradually replace ordinary shaft kilns.