|Application||Cement Plant, Slag Grinding Plant, Steel Mill,
fly ash processing
|Motor Power||1600-5000 kW|
Vertical Slag Mill is the equipment to grind Ground Granulated Blast furnace Slag into small particles. In China, quality slag (fineness:4200-4500cm2/g) produced by vertical roller mills are being used to substitute clinker in conventional cement manufacturing as well as to partially replace OPC for ready-mixed concrete production, for which the percentage of GGBS usage is typically at 10-15% and 20-25% respectively.
1. Iron extraction system
It is a well-known fact that iron particles in the granulated blast furnace slag are the main cause of wear in the mill. Therefore it is extremely important to remove the maximum possible amount of this iron. The external material circuit is very well suited for this purpose, because it handles a large quantity of material, some of which is already partly ground.
2. Wear protection
The grinding plant, which is carefully maintained by the owner, provided high availability and trouble-free operation. None of the wear protection plates in the roller mill housing and in the grit cone of the separator have yet needed replacing. Only the ceramic castable in the upper housing section of the separator was replaced by wear-resistant steel plates soon after the commissioning.
In a vertical roller mill, materials to be ground fall upon the center of a rotating grinding table. Centrifugal force causes the materials to spread out evenly towards the edge of the plate. As particles lying flatly on the plate reach a certain thickness, they are ground or crushed by multiple pairs of rollers.
When the crushed particles fall off the edge of the grinding table, they are met by a strong flow of hot air that has just passed through the nozzle ring at the bottom, which brings them through the center of milling chamber and out the top before entering the separator. During this process, the flying particles absorb enough heat from the hot air, causing the moisture contained in particles to evaporate rapidly.
Once inside the separator, particles finer than the required size pass through the separation device while larger ones fall upon the grinding table once again for further grinding. The desired fully-ground particles enter the finished product warehouse.
1. Combined static and dynamic separators improve the material selection efficiency.
2. Users can start the roller mill without load. The rollers can automatically rise and lower.
3. Arched plates are welded to the mill to maintain the seal. Simple as they may look, these arched structures ensure tight seals.
4. Special devices are added to roller mill so that the rollers can be flipped out of the way to allow easy repair and maintenance.
5. Position-limit mechanism prevents the roller from direct contact or collision with the Grinding Table. This ensures operational safety.
6. The hydraulic system operates at a low pressure, which lowers the risk of oil leak resulting from over pressure. This also helps reduce vibration, facilitating operation and management.
7. Centralized lubricating system makes sure the bearing to be lubricated can operate at a lower temperature and with clean lubricating grease. This provides for extended use life of bearing.
|Model||Grinding Table Diameter (mm)||Roller Diameter (mm)||Roller Number (n)||Motor (kW)||Output (t/h)|
Note: mill spectral pattern benchmark
1. Material medium friction (MFs) =0.9~1.0;
2. Material moisture max. 15%;
3. Refined powder granularity 4200~4500 cm²/g;
4. Refined powder moisture 0.5~1.0%;
5. The concrete mill installed power and technology parameter will be adjusted appropriately basing on the actual material property and requirements of owner.