Industrial Vertical Grinding Mill

Vertical grinding mill is an ideal large-scale grinding equipment, integrating crushing, drying, grinding, and grading and conveying. It is widely used in cement, electric power, metallurgy, chemical, non-metallic mining and other industries. It integrates crushing, drying, grinding, grading and conveying, and has high production efficiency. It can grind bulk, granular and powdery materials into required powdery materials.

Working Principle of Industrial Vertical Grinding Mill

The motor drives the grinding disc to rotate through the reducer. The material falls from the discharge port to the center of the grinding disc. Under the action of centrifugal force, it moves to the edge of the grinding disc and is crushed by the grinding roller. Air ring) The high-speed upward hot air is brought to the high-efficiency separator integrated with the industrial vertical grinding mill. The coarse powder is sorted by the separator and returned to the grinding plate for re-grinding; the fine powder is discharged out of the mill with the air flow and is collected in the system. The dust collected in the device is the product. The coarse particles and metal parts that have not been brought up by the hot air flow and accidentally entered the metal parts sink from the wind ring, and are scraped out by the scraper, and then fed into the mill by the external circulation bucket elevator for grinding again.
vertical grinding mill

Structure of Industrial Vertical Grinding Mill

1. Grinding disc: including guide ring, wind ring, retaining ring, lining plate, disc body, scraper and lifting device, etc.
2. Grinding roller: The roller sleeve is an easy to wear part, which requires sufficient toughness and good wear resistance.
3. Powder separators can be divided into three categories: static, dynamic and high-efficiency combined powder separators:
a. The working principle of the static powder separator is similar to that of a cyclone, with simple structure, no moving parts, and not easy to malfunction. However, the adjustment is not flexible and the separation efficiency is not high.
b. Dynamic powder classifier This is a high-speed rotating cage. When dusty gas passes through the cage, fine particles are brought in by air friction, and coarse particles are directly blocked by the collision of the blades. The speed of the rotor can be adjusted according to requirements, and the speed is high. When, the fineness of the discharge is finer, which is the same as the classification principle of the centrifugal separator. It has high classification accuracy and easy fineness control.
c. The high-efficiency combined powder separator combines the dynamic powder separator (rotating cage) and the static powder separator (wind guide vane) together, that is, a cylindrical cage acts as a rotor, and air guide vanes are evenly distributed around it. The airflow enters the separator area evenly up and down, the coarse and fine powder is separated clearly, and the powder selection efficiency is high. However, the resistance of this classifier is relatively large, so the wear of the blades is also large.
4. Pressure device: hydraulic device, accumulator.
5. Monitoring device: rocker monitoring, vibration monitoring.
6. Transmission device: electric motor, reducer.
7. Water spray system: reduce the temperature and stabilize the material layer.
8. Coarse powder external circulation system: elevator.

Advantage of Industrial Vertical Grinding Mill

1. The production and investment costs are greatly reduced.
The industrial vertical grinding mill system has simple process flow, compact layout, and small building area. It covers an area of ??about 70% of the ball mill system, and the building space is about 60% of the ball mill system. It can be arranged in the open air, which directly reduces the investment cost of the enterprise. And the vertical grinding mill itself has a separator, so there is no need to add a powder separator and lifting equipment. The dust-containing gas from the mill can be directly collected by a bag filter or an electric dust collector.
2. High production efficiency, energy saving and environmental protection
The vertical grinding mill grinds materials by the principle of material layer grinding, with low energy consumption. The power consumption of the grinding system is 20% to 30% lower than that of the ball mill, and the energy saving effect is more obvious as the moisture of the raw material increases. Compared with the ball mill system, the energy consumption of the vertical mill system can be reduced by 30% to 40%. The vertical grinding mill does not have the metal impact sound of the steel balls colliding with each other and the liner in the ball mill, so the noise is low, which is 20-25dB lower than that of the ball mill. In addition, the vertical mill adopts a fully enclosed system, the system works under negative pressure, no dust, and the environment is clean.
3. Strong material drying ability
The vertical grinding mill adopts hot air to transport materials, and when grinding materials with high moisture content, the inlet air temperature can be controlled to make the product reach the required final moisture. It can be dried in the vertical mill—grind materials with a moisture content of up to 15% to 20%.
4. Easy operation and convenient maintenance
Equipped with an automatic control system, it can realize remote control and is easy to operate; by checking and repairing the oil cylinder and turning the boom, the roller sleeve and liner can be replaced conveniently and quickly, and the loss of the enterprise can be reduced.
5. Product quality is stable and easy to detect
The chemical composition of the product is stable, and the particle size is uniform, which is good for calcination. The residence time of the material in the vertical mill is only 2~3min, while it takes 15~20min in the ball mill. Therefore, the chemical composition and fineness of vertical mill products can be quickly determined and corrected.
6. Low wear and high utilization rate.
Because there is no direct metal contact between the grinding roller and the grinding disc in the operation of the vertical grinding mill, the wear is small, and the metal consumption per unit product is generally 5-10g/t.
vertical mill

Disadvantage of Industrial Vertical Grinding Mill

• It is not suitable for grinding hard and abrasive materials, with short service life and frequent maintenance. Moreover, its wear parts are more expensive than ball mills, but compared with the total maintenance of the ball mills, elevators, powder separators and other equipment it replaces, it still appears simple, easy to maintain and has a small workload.
• Compared with ball mills, industrial vertical grinding mills have a higher energy consumption utilization rate. This is the main reason why vertical mills are preferred to the grinding system. However, the fineness of the vertical mills is too uniform and there is no reasonable particle gradation, which limits the application of vertical mills. The main reason for clinker grinding.
• The energy consumption efficiency of the ball mill is low, and there is a tendency to be replaced by vertical grinding mills, roller presses and other equipment. However, the ball mill has the unique advantage of "the particle shape is approximately spherical, which is beneficial to the calcination of raw materials and the hydration and hardening of cement". Material grinding is still the main reason for most use of ball mills.

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