A hammer mill grinder includes a feed conveyor, a press wheel and a rotary hammer mill that is enclosed within a mill box. The mill box presents an intake opening for receiving feed material and a discharge opening for discharging reduced material. The press wheel is located adjacent to the mill box intake opening and is mounted at least indirectly to the mill box for vertical movement. The rotary hammer mill presents hammers that rotate, in cyclic succession, past the intake opening, the press wheel, an inside wall and a screen that is offset from the rotary hammer. The inside wall includes a contaminant bypass door that is able to open to allow a contaminant object to bypass the hammer mill prior to the screen and thereby exit the mill box around the screen to prevent damage to the hammer mill grinder.

A hammer mill grinder includes a feed conveyor, a press wheel and a rotary hammer mill that is enclosed within a mill box. The mill box presents an intake opening for receiving feed material and a discharge opening for discharging reduced material. The press wheel is located adjacent to the mill box intake opening and is mounted at least indirectly to the mill box for vertical movement. The rotary hammer mill presents hammers that rotate, in cyclic succession, past the intake opening, the press wheel, an inside wall and a screen that is offset from the rotary hammer. The inside wall includes a contaminant bypass door that is able to open to allow a contaminant object to bypass the hammer mill prior to the screen and thereby exit the mill box around the screen to prevent damage to the hammer mill grinder.

An impact processing system 10 having a central opening 12 enabling material flow into a primary impact zone 14 in which is located an impact mechanism 16 rotatable about a rotation axis 18. An impact structure 20 provided with a plurality of holes 22 surrounds the impact mechanism 16. The rotatable impact mechanism 16 impacts material entering the primary impact zone 14 from the central opening 12 and accelerate the impacted material in a radial outward direction toward the impact structure 20 to effect fragmentation of the impacted material so that when sufficiently fragmented the material is able to pass through the holes 22. An optional outer structure 30 is radially spaced from the impact structure 20 and may comprise one or more segments that cumulatively extend about the axis of rotation 18 for an angle from 30 and 270 inclusive. A rotatable set of impact members 50 may be located between the impact structure and the outer structure. One or more gaps 28 may be provided in the impact structure 20 to allow the passage of large and/or hard objects that cannot otherwise be fragmented. The outer structure 30 is positioned to span across the gaps 28 so that material passing there thought is directed onto the outer structure 30.

A method and apparatus for grinding a particulate material is disclosed. The method may include providing a system including a roller mill apparatus and a hammermill apparatus, operating the roller mill apparatus and the hammermill apparatus, adjusting a feed rate of particulate material to the roller mill apparatus until power consumption by operation of the roller mill apparatus achieves a target power consumption for the roller mill apparatus, and adjusting a gap between mill rolls of the roller mill apparatus until power consumption by operation of the hammermill apparatus achieves a target power consumption for the hammermill apparatus. The system may include roller and hammermill apparatus with sensing and controlling apparatus configured to operate the roller and hammermill apparatus according to the methods disclosed.

A method and apparatus for grinding a particulate material is disclosed. The method may include providing a system including a roller mill apparatus and a hammermill apparatus, operating the roller mill apparatus and the hammermill apparatus, adjusting a feed rate of particulate material to the roller mill apparatus until power consumption by operation of the roller mill apparatus achieves a target power consumption for the roller mill apparatus, and adjusting a gap between mill rolls of the roller mill apparatus until power consumption by operation of the hammermill apparatus achieves a target power consumption for the hammermill apparatus. The system may include roller and hammermill apparatus with sensing and controlling apparatus configured to operate the roller and hammermill apparatus according to the methods disclosed.

A pin mill includes a rotor plate mounted on a shaft and having concentrically spaced-apart circular arrays of pins arise from an end face. The rotor pins interdigitate with complementary concentric arrays of pins arising from a face of a stator mounted on a door. The door swings open on a hinge mounted on two translator pins so that the door can translate the interdigitated pins before swinging open so that the pins arrays do not collide with each other while the door is opening. The rotor operates within a rotatable cylindrical screen which retains particles being broken up until they are small enough to exit. The rotor includes a circular array of vane knives which sweep closely within the screen and also entrain cooling air into the macerating volume of the mill. Oversized particles trapped in the screen also get cleared and split apart by the passing vane knives.

A pin mill includes a rotor plate mounted on a shaft and having concentrically spaced-apart circular arrays of pins arise from an end face. The rotor pins interdigitate with complementary concentric arrays of pins arising from a face of a stator mounted on a door. The door swings open on a hinge mounted on two translator pins so that the door can translate the interdigitated pins before swinging open so that the pins arrays do not collide with each other while the door is opening. The rotor operates within a rotatable cylindrical screen which retains particles being broken up until they are small enough to exit. The rotor includes a circular array of vane knives which sweep closely within the screen and also entrain cooling air into the macerating volume of the mill. Oversized particles trapped in the screen also get cleared and split apart by the passing vane knives.

An impact processing device has a central impact mechanism arranged to rotate about a rotation axis and a first processing stage that includes the impact mechanism and a first structure extending circumferentially about the impact mechanism. The first structure has a first processing sector, and a first screening sector, where the processing sector extends for a first circumferential portion of the first structure and has an impervious textured surface and the first screening sector has a plurality of holes and extends for a second circumferential portion of the first structure. The impact mechanism is operable to impact material against the first processing sector and generate a flow of the impacted material to first screening sector through which at least a portion of the impacted material can pass.

An impact processing device has a central impact mechanism arranged to rotate about a rotation axis and a first processing stage that includes the impact mechanism and a first structure extending circumferentially about the impact mechanism. The first structure has a first processing sector, and a first screening sector, where the processing sector extends for a first circumferential portion of the first structure and has an impervious textured surface and the first screening sector has a plurality of holes and extends for a second circumferential portion of the first structure. The impact mechanism is operable to impact material against the first processing sector and generate a flow of the impacted material to first screening sector through which at least a portion of the impacted material can pass.

The present disclosure relates to the treatment of streams derived from construction and/or demolition (C&D) debris, such as C&D fines streams, asphalt shingles, drywall, or wood. The process can include a kinetic pulverization stage through a kinetic pulverizer where the frangible materials are size-reduced and the ductile materials are liberated and remain as an oversized fraction. The feedstock can include infrangible materials that also remains as an oversized fraction. The pulverized material is then subjected to a separation stage, which may include mechanical and/or magnetic screening, to separate the oversized material comprising the ductile material, and optionally larger particles of the infrangible material, from the size-reduced material comprising the frangible material, and optionally small particles of infrangible material.