Abstract: A refiner (1) comprising a stator (2) and a rotor (4). The stator (2) and the rotor (4) comprise a flat portion (7, 9) and a conical portion (8, 10). The conical portion has a first end (17) of smaller diameter (D1) and a second end (18) of greater diameter (D2) such that the first end is directed towards the flat portion and the second end is directed away from the flat portion. The refining surface (12) of the conical portion of the stator comprises at least an outer zone (23) arranged at the second end of the conical portion and an inner zone (22) arranged relative to the outer zone on the side of the first end of the conical portion. A portion of the length of the blade bars (20) in the outer zone are arranged relative to the rotation direction (RD) of the rotor such that they have a retentive effect on the material to be refined. Also a blade segment (19) for a conical portion of a stator of a refiner.

Abstract: A refiner (1) comprising a stator (2) and a rotor (4). The stator (2) and the rotor (4) comprise a flat portion (7, 9) and a conical portion (8, 10). The conical portion has a first end (17) of smaller diameter (D1) and a second end (18) of greater diameter (D2) such that the first end is directed towards the flat portion and the second end is directed away from the flat portion. The refining surface (12) of the conical portion of the stator comprises at least an outer zone (23) arranged at the second end of the conical portion and an inner zone (22) arranged relative to the outer zone on the side of the first end of the conical portion. A portion of the length of the blade bars (20) in the outer zone are arranged relative to the rotation direction (RD) of the rotor such that they have a retentive effect on the material to be refined. Also a blade segment (19) for a conical portion of a stator of a refiner.