US Patent 7971815 Milling station and method for grinding milling material

A milling station and a method for grinding milling material using at least one coarse grinding circuit and at least one fine grinding circuit. The coarse grinding circuit includes a classifier and a material bed roller mill. The fine grinding circuit includes a tube mill with at least two grinding chambers, a central outlet, and a divider. In some instances, at least some of the milling material from the coarse grinding circuit is subdivided in the divider and delivered to the at least two grinding chambers of the fine grinding circuit while some of the milling material is jointly discharged from the at least two grinding chambers through the central outlet.