Vertical roller mill final grinding plant Solution
Capacity: 700 ~ 5,000 TPD
Main Grinding Equipment: vertical roller mill
Material: cement clinker
Working Process: cement vertical mill final grinding (closed circuit)
Solution: EPC service providing including design, procurement, construction, and trial operation
Solution Introduction
The vertical roller mill final grinding plant is a cement grinding station that uses a vertical roller mill alone as the main grinding equipment to achieve the final grinding effect. A complete vertical mill production line includes the crusher, elevator, storage hopper, vibrating feeder, vertical roller mill, classifier, dust collector, vertical fan, air compressor, electrical control system, etc.
Four mainstream grinding systems according to the cement mills using
ball mill final grinding system
ball mill final & vertical mill combined grinding system
vertical roller mill final grinding system
Cement grinding unit process with VRM mill
First Step： Proportioning bin
Cement clinker, gypsum, and additives are transported through the elevator separately to the proportioning bin.
Second Step： Belt conveyor feeder
Cement clinker, gypsum, and additives are mixed according to the proportion desired under the proportioning bin by the calculating system and loaded on the belt conveyor.
Third Step： Bucket Elevator
The prepared raw materials are delivered to the cement vertical mill with the help of an elevator.
Fourth Step： Cement vertical mill grinding
The raw materials are dried and ground in the vertical roller mill. The motor drives the grinding plate to rotate through the reducer, and the hot air enters the vertical mill from the air inlet. The raw material falls from the discharge port to the center of the grinding plate and moves evenly from the center to the edge under the action of centrifugal force. At this time, the bulk material is crushed, and the fine-grained material is crushed and crushed. The crushed materials continue to move to the edge of the grinding plate until they are taken away by the strong airflow at the air ring, and the larger granular materials fall back to the grinding plate for regrinding.
Fifth Step: Separator (Classifier)
The qualified fine powder is brought into the classifier for sorting with the circulating air of the blower. By adjusting the separator, the desired coarse particle size for different products can be achieved.
Sixth Step: Dust collector
The qualified fine powder passes through the bag filter with the airflow. The dusty gas is collected by the dust collector. The finished cement powder is separated and produced.
Seventh Step: Fan
The fan is installed behind the dust collector to meet the equipment resistance requirements and required air volume so that the airflow through the cement mill remains stable.
Eighth Step: Conveying and storage
The spiral conveyor sends the finished cement out from the dust collector to the storage silo.
Advantages & disadvantages of cement vertical mill final grinding system
Advantage
High efficiency of grinding and lower power consumption. 20-30% lower than cement ball mill.
The vertical mill grinding system has a strong drying capacity, using the new hot blast stove as an auxiliary heat source, which can dry 20% of the raw material moisture.
Allows the grinding material to have a large particle size （80-120mm）while the ball mill (＜30mm).
Small areas are required with low civil engineering costs which can save about 30%.
Less noise, 10db lower than ball mills.
Less wear and maintenance thus longer service life.
Disadvantage
Because the finished product is completely produced by extrusion, the particle gradation is not ideal, and the particle surface shape is not conducive to the hydration and strength of cement.
Related project
| Grinding materials | cement clinker, gypsum, and other auxiliary materials |
| Capacity | 3000t/d |
| Feeding particle size | clinker <10mm max.50mm |
| Feed moisture | max.15%H2O |
| Product fineness | Cement: specific surface area >340m2/g |
| Product moisture | <0.5%H2O |
