There is provided a refining device including: a casing; a rotor having a rotation shaft, a first rotor portion positioned on a charging port side, a second rotor portion positioned on a discharge port side, and a partition wall, and disposed on an inside of the casing; and a liner disposed on an inner surface of the casing along an outer periphery of the rotor, in which the first rotor portion has a plurality of first blades radially installed around the rotation shaft through a gap portion which is open on the charging port side and blocked by the partition wall, the second rotor portion has a plurality of second blades radially installed around the rotation shaft, and in a state where the rotor is rotating, the raw material charged from the charging port is refined when sequentially passing between the gap portion and the adjacent first blades and when sequentially passing between the first blade and the liner and between the second blade and the liner, and is discharged from the discharge port.

A fiber processing system includes a fiber processing unit having an inlet, accepts outlet, and solid discharge outlet and configured to remove solid contaminants from a fiber-containing stream to produce an accepts stream exiting the accepts outlet and a solid discharge stream exiting the solid discharge outlet. The fiber processing system includes an optical system having an imaging device and image processing system. The imaging device is configured to capture images of the solid discharge stream at or downstream of the solid discharge outlet, and the image processing system is configured to determine relative fiber content, a relative generation rate, types of materials in, or combinations thereof of the solid discharge stream from the captured images. The fiber content, generation rate, and/or types of materials of the solid discharge stream are used to control operation of the fiber processing system or other upstream pulp processing equipment.

A fiber processing system includes a fiber processing unit having an inlet, accepts outlet, and solid discharge outlet and configured to remove solid contaminants from a fiber-containing stream to produce an accepts stream exiting the accepts outlet and a solid discharge stream exiting the solid discharge outlet. The fiber processing system includes an optical system having an imaging device and image processing system. The imaging device is configured to capture images of the solid discharge stream at or downstream of the solid discharge outlet, and the image processing system is configured to determine relative fiber content, a relative generation rate, types of materials in, or combinations thereof of the solid discharge stream from the captured images. The fiber content, generation rate, and/or types of materials of the solid discharge stream are used to control operation of the fiber processing system or other upstream pulp processing equipment.