Air swept coal mill

Description

The drying air sweep grinding technology is simply that the material is crushed and dried during the grinding process. Because the material stays in the mill for a long time and is crushed while drying, the large particle material is dispersed in the hot air and the surface is dried and the particle size is decreasing. Small particles and powdery materials: suspended in the hot air, directly in full contact with the hot air, the contact area is large, and the heat exchange quickly makes it dry instantaneously.

At the same time, due to the high wind speed in the mill, the water vapor and fine powder generated in the drying and grinding process can be discharged outside the mill in time, avoiding the undesirable phenomena such as sticky ball, paste grinding and blockage, and reducing the opportunity of grinding and forming the material pad, so the grinding efficiency of the mill is very high. With the development of dry production in cement industry, the technology of raw material drying air sweeping grinding system has become more and more mature and has received more and more attention. According to the situation of small and medium-sized cement 傿 raw material grinding, Global Heavy Industry has invested heavily in the research and production of new raw material drying air sweeping grinding technology and equipment on the basis of original experience, which has been widely applied to raw material grinding water. No dryers or small raw mill with poor drying and low yield technical transformation. This product has a large production range and saves electricity; Compared with the use of dryers, it can save 40 to 70 percent of coal, and is a substitute for dryers. The equipment technology is mature and reliable.

Performance Advantages

• 01
  High grinding efficiency, easy fineness adjustment: continuous production, large production capacity, high grinding efficiency, easy fineness adjustment, small energy loss.
• 02
  Strong adaptability: strong adaptability to materials, can grind and dry various hardness of coal.
• 03
  Smooth feed, no clogging phenomenon: the feed device of the mill adopts the louver structure of oblique air intake and oblique feed, which enhances the heat exchange capacity of the mill and makes the feed more smooth, so as to effectively prevent the clogging phenomenon of the coal mill inlet.
• 04
  Less transmission parts, low maintenance costs: compact equipment structure, fewer transmission parts, low maintenance costs, smooth operation, easy installation.

Working Principle

Raw coal enters the feeding device of the wind-swept coal mill from the feeding equipment, and the hot air with a temperature of about 300℃ also enters the feeding device through the air inlet pipe. The raw coal is raised by a special lifting plate in the drying bin, so that the raw coal is dried after intense heat exchange here, and the dried coal enters the grinding bin through the double compartment plate equipped with the lifting plate. A grinding body (steel ball) is installed in the pulverizing bin, in which the coal is crushed and ground into pulverized coal. At the same time when the coal is crushed, the pulverized coal and gas are taken out of the mill by the special induced draft fan through the discharge device of the wind-swept coal mill, and the coarser particles are returned to the grinding bin through the return screw of the discharge device for re-grinding.

More Pictures

Question&Answer

Q:What is the cause of insufficient drying capacity?

A:The length ratio between the drying bin and the grinding bin is 1∶1.67, and the drying heat source of the raw coal into the grinding is provided by the high temperature fan. The thermal insulation effect of the hot air from the fan to the inlet of the coal mill is not good, the heat loss is serious, and the temperature of the hot air into the grinding is as high as 100℃. The actual temperature of the air into the grinding is only about 190℃, resulting in insufficient drying capacity in the mill. The moisture content of pulverized coal exceeds the standard.

Q:What is the cause of insufficient grinding capacity?

A:Compared with the production capacity of the kiln system, the grinding capacity of the wind-swept coal mill itself is lacking, and the use of inferior coal has poor grindability and needs to be ground finer. This is very unfavorable to the high yield and fine requirements of coal mill, and the grinding capacity is insufficient.

Technical Data: