Separation device

A separation device comprising:

• a mesh that has a first surface and a second surface in a front and back relationship;
• a separation unit that has
• a first ejection unit having a first ejection port for depositing a defibrated material containing pieces of fibers on the first surface, and
• a first suction unit having a first suction port for sucking from the first surface toward the second surface so that at least a part thereof overlaps the first ejection port in plan view;
• a second suction unit provided at a position different from the first ejection port in plan view and having a second suction port for sucking from the second surface toward the first surface;
• a detection unit disposed between the first ejection unit and the second suction unit to detect information on foreign matter contained in the defibrated material ejected from the first ejection port and deposited on the mesh before being subjected to suction by the second suction unit;
• an input unit that inputs a detection result of the detection unit;
• and
• a control unit that controls a separation condition in the separation unit based on the information input to the input unit.