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 processing plate (4, 12) for mechanically processing pulp. The plate has projecting parts (6, 7, 14, 15). The projecting parts (7, 15) comprise a radially inner part (28) having an inclined ascending wall (29) towards the outer periphery (23) of the plate and a radially outer part (30) having an inclined descending wall (31) towards the outer periphery (23) of the plate (4, 12). The inner and outer parts (28, 30) are radially coupled to each other by a ridge (32) along a coupling line (CL). The walls (29, 31) are mutually connected only partly so that they have in common only a crest section (40) of the ridge (32) which crest section (40) is less than a width of at least one of the wall (29) of the inner part (28) and the wall (31) of the outer part (30) at the coupling line (CL).

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.

A blade segment (4, 4a, 4b, 8, 8a, 8b) for a refiner (1) for refining fibrous material has first (20) and second (21) end edges and first (22) and second (23) side edges, the first (22) and second (23) side edges extending between the first (20) and second (21) end edges. The segment has a refining surface (5, 9) with blade bars (27) and grooves (28) on the segment front surface (25). At least one opening (14, 15) at the side edge (22, 23) extends through the whole thickness of the segment body (24) and towards the opposite side edge (22, 23). A guide element projects from the segment background surface (26) at the side edge which provides a guide surface that intensifies the feed of the material to be refined through the opening to the refining surface of the blade segment into the refining chamber of the refiner.

A disperser-refiner plate segment includes a refining section disposed radially outward from a dispersion section. Teeth in the dispersion section have a height that exceeds a height of refining bars in the refining section.

The present invention relates a process to produce microfibrillated cellulose and a microfibrillated cellulose produced according to such process. The fibrillated microfibrillated cellulose is obtained subjecting a cellulose fiber in a slurry of cellulose pulp to multiple mechanical impacts. The cycle may be repeated several times. Non-cutting bars disposed in a ring formation is the preferred method. Two rings concentrically arranged facing each other in high rotation transmit the kinetic energy to the fibers to provide the highly defibrillated microfibrillated cellulose.

A refiner includes two or more facing refining assemblies. Each refining assembly includes a backing structure and refiner plate segments engaged to the backing structure A series of alternating bars and grooves defines a refining surface on each refiner plate segment. The refiner plate segments of the first refining assembly have a terminal edge perimeter defined by two or more terminal edges of bars disposed closest to the outer arc of the substrate of the first refining assembly. The refiner plate segments of the second refining assembly have an outermost edge circumference defined by an outermost terminal edge of a bar disposed closest to the outer arc of the substrate of the second refining assembly facing the first refining assembly. The terminal edge perimeter of the first refining assembly is not parallel to the outermost edge circumference of the second refining assembly.

The present invention relates to a blade for a disc refiner intended for refining lignocellulosic material, the blade (10) comprising a surface (1) delimited by an inner circumference (11) and an outer circumference (12), a refiner zone (2) on the surface (1) for refining lignocellulosic material, a blank zone (3) on the surface (1), wherein the refiner zone (2) is arranged closer to the inner circumference (11) than the blank zone (3), the blade (10) further comprising a separation groove (4) that is arranged between the refiner zone (2) and the blank zone (3), and at least one connecting groove (5) that connects the separation groove (4) to the outer circumference (12) of the blade (10) across the blank zone (3). The invention also relates to a blade pair and to a refiner comprising at least one blade.

The present invention relates to a blade for a disc refiner intended for refining lignocellulosic material, the blade (10) comprising a surface (1) delimited by an inner circumference (11) and an outer circumference (12), a refiner zone (2) on the surface (1) for refining lignocellulosic material, a blank zone (3) on the surface (1), wherein the refiner zone (2) is arranged closer to the inner circumference (11) than the blank zone (3), the blade (10) further comprising a separation groove (4) that is arranged between the refiner zone (2) and the blank zone (3), and at least one connecting groove (5) that connects the separation groove (4) to the outer circumference (12) of the blade (10) across the blank zone (3). The invention also relates to a blade pair and to a refiner comprising at least one blade.

A refining disc (6) in a defibrator (1) for refining fibrous material is provided with non-central openings (11) for allowing steam developed in the refining space (2) during refining to flow from the front side to the backside of the refining disc (6), where the front side is facing a second refining disc (5) and the backside is facing away from the second refining disc (5). The refining disc (6) also comprises a central hole (12) for allowing steam (8b) to flow from the backside to the front side at the rotational center of the refining disc (6), and escape from the defibrator (1) backwards through the feed screw (3a) without passing through the fibrous material (7) being refined in the refining space (2).