A refiner plate that is adapted to be attached to a rotatable refiner disc on a refiner for mechanical treatment of lignocellulosic material. The refiner plate includes a refining surface that is adapted to be arranged oppositely a second refining surface of a second refiner disc on said refiner. The refining surface is provided with a plurality of refining bars, where at least one of the refining bars is provided with cavities that are at least partially embedded in the refining bars. At least one cavity provided on the at least one refining bar have one end arranged closer to the leading edge of a refining bar and one end arranged closer to the trailing edge of the refining bar and wherein the depth dimension of the cavity at the end is smaller than the depth dimension of the cavity at the end.

An assembly comprising an annular hub with a hub inner surface and a hub outer surface and a rotary third refining member having a central opening within a refining member inner surface. The refining member has at least two equally spaced apart member portions extending radially inwardly from the member inner surface, and the assembly includes a key for connecting the member portions to the hub. The assembly also include an annular cover plate with at least two radially extending spaced apart flanges, each flange overlying a member portion, and at least two spaced apart port plates, each port plate overlying a member portion side opposite the annular cover plate, the spaces between the at least two port plates defining ports from a first stock flow path to a second stock flow path.

A refining member including a refining body with a refining surface including first and second refiner bars separated by first and second refiner grooves. The first and second refiner bars extend from respective first and second radially inward positions to respective first and second radially outward positions. The first and second refiner bars have a respective first and second height extending upward from a floor of a respective, adjacent first or second refiner groove. The second height is a minimum height of the second refiner bars and is spaced apart from the second radially inward position, with the second height being at least about 0.35 mm less than the first height. The first refiner bars are adapted to refine wood fibers and the second refiner bars are adapted to break up fiber bundles.

A blade segment (4, 8) for a refiner (1) for refining fibrous material has first (20) and second (21) end edges opposite one another in a direction of a longitudinal axis (LA) of the blade segment (4, 4a, 4b, 8, 8a, 8b), and first (22) and second (23) side edges which extend between the first end edge and the second end edge. The blade segment has a refining surface (5, 9) with blade bars (26) and grooves (27) therebetween on a front surface (25) of the blade segment (4, 8). At least one side edge (22, 23) has at least two edge portions (31, 33, 35, 41, 43, 45) arranged to deviate from the direction of the longitudinal axis (LA) of the blade segment (4, 4a, 4b, 8; 8a, 8b) and connected by an elbow (32, 34, 42, 44) between each two edge portions (31, 33, 35, 41, 43, 45).

A refiner for refining of lignocellulosic material includes a rotor disc and a stator disc. The rotor disc includes a first refining segment that includes a plurality of first protruding structures for grinding of the lignocellulosic material. Each of the first protruding structures is defined by a first height. The stator disc is arranged opposite the rotor disc and includes a second refining segment that includes a plurality of second protruding structures for grinding of the lignocellulosic material. Each of the second protruding structures being defined by a second height. The first height is at least three times larger than the second height.

A blade segment (4, 8) for a refiner (1) for refining fibrous material has a first (20) and a second (21) end edge and a first (22) and a second (23) side edge opposite to the first side edge (22) and a refining surface (5, 9) having blade bars (27, 27a, 27b) and grooves (28, 28a, 28b) therebetween on a front surface (25). At least one opening (14, 15) is on at least at one side edge (22, 23) which extends through the whole thickness of the blade segment body (24). There is at least one feed groove (29) on the refining surface, the feed groove (29) extending from the opening and crossing the blade bars and the blade grooves for feeding the material to be refined across the refining surface. The blade bars (27, 27a, 27b) of the blade segment are interlaced at the feed groove.

A refiner segment that includes a center area. The refiner segment includes a number N, N≥2, of bar zone that are arranged at different radial positions with regard to a radial direction R extending from the center area of the refiner disc towards the periphery of the refiner segment. Each of the bar zones are defined by a corresponding set of refining bars that are distributed angularly and encircles the center area. The refining bars belonging to different but neighboring bar zones are angularly offset and refining bars belonging to different but neighboring bar zones are arranged in such a way that a tangential direction of a particular refining bar belonging to a bar zone points in a direction towards the mid-point between two refining bars belonging to a neighboring bar zone.

A first refining disc (5) for a defibrator (1) for refining fibrous material, adapted to receive a flow of incoming fibrous material (7) from a feed screw (3a) through a material inlet opening (4) arranged in the first refining disc (5), is provided with at least one steam evacuating channel (21) comprising at least one steam inlet opening (22) arranged on a side of the first refining disc (5) adapted to face a second refining disc (6), and at least one steam outlet opening (23) arranged on a side of the first refining disc (5) adapted to face away from the second refining disc (6). The at least one steam outlet opening (23) is arranged centrally of the at least one steam inlet opening (22) with respect to the center of the first refining disc (5), and centrally of a position where the flow of incoming material (7) is to be received into the first refining disc (5) from the feed screw (3a), with respect to the center of the first refining disc (5).

A method of making a market pulp can include separating a slurry comprising a plurality of pulp fibers into at least first and second pulp feeds. The first pulp feed can be refined at least by, for each of one or more mechanical refiners, introducing the first pulp feed between two refining elements of the refiner and rotating at least one of the refining elements, each of the refining elements comprising a plurality of bars and a plurality of grooves, where a width of each of the bars is less than or equal to 1.3 mm and a width of each of the grooves is less than or equal to 2.5 mm. The refiner(s) can consume at least 300 kWh per ton of fiber. The refined first pulp feed and second pulp feed, which is not refined, can be combined to produce a third pulp feed that can be dried.

A blade element (4, 8) for a comminution device (1) to comminute fiber material has at least one comminution section (22) with comminution parts (20, 24, 25, 26) and free spaces (21) therebetween, and at least one feed section (23) extending at least partly in a longitudinal direction (X) of the blade element (4, 8), each feed section (23) intended to feed fiber material to the respective comminution section (22). The comminution parts have a first dimension (d20a, d20b, d20c, d24a, d24b, d24c) extending in a circumferential direction (C) of the blade element and a second dimension (e20a, e20b, e20c, e24a, e25a, e26a) extending in the longitudinal direction (X) of the blade element. At the same longitudinal (X) position in the blade element (4, 8) the first dimension of the comminution parts is arranged to increase in the circumferential direction (C) of the blade element toward the feed section.