The vertical roller mill fulfills four main functions in one compact piece of equipment:
The process is called a drying /grinding process, where most of the material/product is transported pneumatically by drying gases.
Grinding: the material is ground between rollers and grinding table while passing from the center of the table to the nozzle ring. The commnation method belongs to the most efficient grinding processes applied in the cement manufacturing.
Separation: the ground and dried material is lifted up with the drying gases. In the separator, the too coarse particles (tailings) are rejected to the grinding table. The fines leave the mill and are conveyed to dust collector.
Drying: the process air consists mostly of waste gas from a kiln or cooler or is supplied by a hot gas generator. Drying occurs during transport through the grinding and separating process stage.
Transport: the drying gasses are utilizing to serve as conveying media. The first transport stage is the internal circulation and the second is the separator. At last, the product is extracted from the separator and pneumatically conveyed to cyclones or a filter where the product is collected and fed to a silo. The clean gases are exhausted to the ambient and/ or re-circulated to the mill.