Vertical roller mill is a kind of grinding machine for cement, raw material, cement clinker, slag and coal slag. It has the features of simple structure and low cost of manufacture and use. Vertical roller mill has many different forms, but it works basically the same.
The milling/grinding process doesn't raise the temperature of the flour by more than 112 F (45 C) to protect the integrity of the flour ... My personal opinion is that there is little incentive to buy an impact mill. Although it may cost less than a burr grinder, it won't grind to an ultra fine flour.