Abstract: The aim of the invention is to create a compact circulating grinding plant comprising a product bed comminution roller mill or roller press and a sifter device, in which the problem of mechanically transporting the grinding product that is directed through the circuit is minimized. Said aim is achieved by a circulating grinding plant in which a static cascade sifter is disposed below the gap of the roller press while a subsequent sifter, particularly a dynamic rod basket sifter, is disposed above said roller press. The sifting product discharge area of the static cascade sifter is connected to the sifting air and sifting product inlet of the subsequent sifter via an ascending duct which pneumatically conveys the product.

Abstract: In order to further develop a circuit grinding apparatus with a roller mill or roller press for material bed disintegration of granular material and with at least one integrated sifter, where the mill and the sifter are disposed within two stationary side walls between which a material conveyor ring is rotatably seated and can be set into rotation for an internal circulation of material in such a way that the rotatably seated material conveyor ring, which has a very large diameter and rotates in operation, is as light as possible and the rotary actuator is configured as simply as possible, it is proposed in accordance with the invention to dispose around the bottom circumferential area of the material conveyor ring more than two, for example four rolls supporting the ring on the bottom, where two adjacent bearing rolls in circumferential direction of the ring are positioned at the ends of at least one common rocker lever which, in turn, is supported on the machine frame via a tilting joint.

Abstract: In order to further develop a circuit grinding apparatus with roller mill or roller press for comminution of the material bed of granular material and with at least one integrated sifter, in which mill and sifters are arranged within two fixed side face walls with an interlying turnably borne material conveyor ring settable into rotation for an internal material circuit, so that seals between the fixed side face walls and the interlying material conveyor ring that is settable in rotation are no longer necessary, it is proposed according to the invention to combine the two fixed side face walls over a housing part that houses the rotatable material conveyor ring, especially a ring housing part, into a housing tightly enclosing the entire working space of the circuit grinding apparatus, and to arrange on the underside of the housing part at least one grinding material leakage discharge from the working space of the circuit grinding apparatus.

Abstract: In order to further develop a circuit grinding apparatus with a roller mill or roller press for material bed disintegration of granular material and with at least one integrated sifter, where the mill and the sifter are disposed within two stationary side walls between which a material conveyor ring is rotatably seated and can be set into rotation for an internal circulation of material in such a way that the rotatably seated material conveyor ring, which has a very large diameter and rotates in operation, is as light as possible and the rotary actuator is configured as simply as possible, it is proposed in accordance with the invention to dispose around the bottom circumferential area of the material conveyor ring more than two, for example four rolls supporting the ring on the bottom, where two adjacent bearing rolls in circumferential direction of the ring are positioned at the ends of at least one common rocker lever which, in turn, is supported on the machine frame via a tilting joint.