Patent ID: 7350727

Claim:
A roller mill operating on a grinding material containing magnetizable constituents, the roller mill comprising: a mill casing defining a milling area; a grinding pan having a grinding path, the grinding pan rotatably mounted in the milling area; at least one grinding roller in the milling area of the mill casing for rolling on the grinding material on the grinding path of the grinding pan; slave rollers located upstream of the at least one grinding roller and rolling on the grinding material for preparing the grinding material, wherein one of the slave rollers is a roller including an electromagnetic device for separating the magnetizable constituents from the milling area, the roller including the electromagnetic device having a roller-like construction for rolling on the grinding material for separating the magnetizable constituents from the grinding material and including a nonmagnetic roller jacket and an interior, wherein the electromagnetic device has an adjustable electromagnet having an iron core and electrical coils which are located in the interior of the nonmagnetic roller jacket; an integrated classifier above the milling area; a vane ring located between the grinding pan and the mill casing; a ring duct below the vane ring; and a discharge mechanism connected to the electromagnetic device for removing the separated, magnetizable constituents from the milling area, wherein the discharge mechanism removes the separated, magnetizable constituents from the roller including the electromagnetic device and discharges the same from the milling area, the discharge mechanism including at least one stripper near the roller jacket, a downcomer downstream of the stripper, a closing flag for gas flow from the ring duct provided in the downcomer, and a conveyor trough between the stripper and the downcomer.