Blade elements for refiners

Abstract

A blade element (4,8) for a refiner (1) for refining fibrous material and a refiner (1) for refining fibrous material. The blade element (4,8) includes a first edge (18) to be oriented toward the feed of the fibrous material to be refined and a second edge (19) to be oriented toward the discharge of the refined fibrous material, and a refining surface (5,9) including blade bars (16) and blade grooves (17) therebetween. The refining surface (5,9) includes at least one equalizing pocket (23) extending along the refining surface (5,9) of the blade element (4,8) and intersecting the multiple blade bars (16) and multiple blade grooves (17) to equalize the flow of fibrous material along the refining surface (5,9).

Description

[Technical Field]

[0001] The present invention relates to a refiner for refining fibrous material, and more particularly to a blade element for a refiner for refining fibrous material.

[0002] Refiners for refining fibrous materials, such as those used to produce mechanical pulp or in any low consistency refining, typically include two refining elements that face each other and rotate relative to each other, i.e., one or both are rotating. The refining elements include a refining surface with blade bars and blade grooves between them, where the blade bars are intended to macerate and refine the material to be refined, and the blade grooves are intended to carry the material to be refined forward along the refining surface. The refining surface of a refining element is typically formed by several blade segments fastened to the body of each refining element. Thus, the complete refining surface of a refining element is formed by the refining surfaces of several blade segments fastened adjacent to each other in the refining element.

[0003] All processes for producing pulp from lignocellulosic materials produce shives, an undesirable quality issue. Shives are particles or bundles of fibers or pieces of wood that are created by incomplete separation of wood into fibers during cooking or mechanical processing. Shives not only impair the quality of the pulp produced, but also impair the operation of some processing devices, such as refiners. [Background technology]

[0004] Low-consistency refining, or LC refining, is increasingly being used in the production of chemi-thermomechanical pulp (CTMP). At low consistency, the consistency of the material to be refined is less than 6%, typically between 1% and 4%. The problem of producing high-quality pulp when the particle size distribution of the pulp is very broad is particularly pronounced in low-consistency refining, especially with regard to debris control. Debris tends to clog the refining surface, thereby reducing the quality of the refined material and the capacity of the refiner. Summary of the Invention [Problem to be solved by the invention]

[0005] SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel blade element for a refiner for refining fibrous material and a novel refiner for refining fibrous material. [Means for solving the problem]

[0006] The invention is characterized by the features of the independent claims.

[0007] The present invention is based on the idea of ​​at least one equalizing pocket extending along the refining surface of the blade element and intersecting with a number of blade bars and a number of blade grooves, which equalizes the flow of fibrous material along the refining surface.

[0008] In the equalization pocket, at least a portion of the flow of fibrous material being refined on the refining surface is interrupted to allow it to equalize or balance before proceeding further on the refining surface.

[0009] Some embodiments of the invention are disclosed in the dependent claims.

[0010] In the following, the invention will be described in more detail by means of preferred embodiments with reference to the accompanying drawings. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 2 is a schematic cross-sectional side view of a conical refiner.

[0012] [Figure 2] 2 is a schematic plan top view of a blade element applicable for use in the refiner of FIG. 1. FIG.

[0013] [Figure 3] FIG. 3 is a schematic plan top view of a detail of the blade element of FIG. 2. DETAILED DESCRIPTION OF THE INVENTION

[0014] For reasons of clarity, the drawings illustrate some embodiments of the invention in a simplified manner. Like reference numerals refer to like elements throughout the drawings.

[0015] FIG. 1 shows a schematic side cross-sectional view of a conical refiner 1, which may be used to refine fibrous materials, such as lignocellulose-containing wood materials or other fibrous materials suitable for use in producing paper or paperboard. The refiner 1 shown in FIG. 1 is of the conical type, but disc refiners, conical disc refiners, and cylindrical refiners may be used in the present example as well. Generally, refiners include at least two substantially oppositely positioned refining elements, at least one of which is rotating, and a refining chamber formed between each of the two substantially oppositely positioned refining elements. Below, refiners with only one rotatable refining element are described.

[0016] The refiner 1 of Figure 1 includes a frame 2 and a stationary, fixed refining element 3, i.e., a stator 3, supported by the frame 2. The frame 2 provides a body for the stator 3, unless the stator 3 has a separate body fastened to the frame 2 of the refiner 1.

[0017] The stator 3 includes one or more stator blade elements 4, each including a blade bar and a blade groove therebetween. The blade bars and blade grooves in each of the one or more stator blade elements 4 define a refined surface 5 for the respective blade element 4. The complete refined surface of the stator 3 is either defined by the refined surface 5 of a single stator blade element 4 extending around the entire circumference of the stator 3, or by the refined surfaces 5 of two or more blade elements 4 having the shape of blade segments and fastened together within the stator 3 so as to provide a complete refined surface 5 extending around the entire circumference of the stator 3. In the latter case, the refined surface 5 of each stator blade segment 4 provides only a portion of the refined surface of the stator 3. For clarity, the same reference numeral 5 is used herein to refer to both the refined surface of each one or more stator blade elements 4 and the complete refined surface of the stator 3. Additionally, the same reference numeral 4 may be used to refer to both segmented blade elements for the stator 3 and a single blade element extending around the entire circumference of the stator 3.

[0018] The refiner 1 further includes a rotatable refining element 6, i.e., a rotor 6, of the refiner 1. The rotor 6 includes a hub 7. The rotor 6 further includes one or more rotor blade elements 8 supported on the hub 7, each of the one or more rotor blade elements 8 including blade bars and blade grooves therebetween. The blade bars and blade grooves in each of the one or more rotor blade elements 8 form a refining surface 9 of the respective blade element 8. The complete refining surface of the rotor 6 is either formed by the refining surface 9 of a single rotor blade element 8 extending around the entire circumference of the rotor 6, or by the refining surfaces 9 of two or more blade elements 8 having the shape of blade segments and fastened together within the rotor 6 to provide a complete refining surface 9 extending around the entire circumference of the rotor 6. In the latter case, the refining surface 9 of each rotor blade segment 8 provides only a portion of the refining surface of the rotor 6. For clarity, both the refined surface of each one or more rotor blade elements 8 and the complete refined surface of rotor 6 are designated herein by the same reference numeral 9. Additionally, the same reference numeral 8 may be used below to designate segmented blade elements for rotor 6 as well as a single blade element extending around the entire circumference of rotor 6.

[0019] The hub 7 of the rotor 6 is connected to a drive motor 10 by a shaft 11 so that the rotor 6 can be rotated relative to the stator 3, for example, in the direction of arrow RD, which thus indicates the intended direction of rotation 5 of the rotor 6.

[0020] The refiner 1 may include a loading device, not shown in FIG. 1 for clarity. The loading device can be used to move the rotor 6, which is attached to the shaft 11, back and forth as shown diagrammatically by arrow A to adjust the size of the refining gap 12 between the stator 3 and the rotor 6, i.e., the refining chamber 12, in which the fibrous material is actually refining. The structure and operation of different applicable loading devices are generally known to those skilled in the art of refining and therefore will not be disclosed in more detail herein.

[0021] The fibrous material to be refined is fed to refiner 1 through feed channel 13 in the manner indicated by arrow F. The fibrous material fed to refiner 1 proceeds to refining chamber 2 through a first end 12' or feed end 12' of refining chamber 12, which has a smaller diameter. In refining chamber 12, the fibrous material is macerated and refined while the water contained in the material evaporates. The already refined fibrous material flows out of refining chamber 12 through a second end 12'' or discharge end 12'' of refining chamber 12, which has a larger diameter, into discharge chamber 14, and the refined material is removed from refining chamber 1 through discharge channel 15, as indicated schematically by arrow D.

[0022] It is emphasized that in addition to conical refiners, the blade elements of the solution described herein are also applicable to disc refiners and cylindrical refiners as well as refiners including both conical and disc sections.

[0023] Figure 2 is a schematic top plan view of a blade element 4, 8 having the form of a blade segment 4, 8 applicable to be used to form a portion of the refining surface 5, 9 of a stator 3 or rotor 6, whereby the complete refining surface 5, 9 is provided by adjacently arranging the required number of blade segments 4, 8 of Figure 2 around the circumference of the stator 3 or rotor 6. The blade element embodiments disclosed below are also applicable, to an appropriate extent, to a single blade element extending around the entire circumference 35 of the stator 3 or rotor 6. Figure 3 is a schematic top plan view of a detail of the blade element of Figure 2.

[0024] The blade segments 8 include, at their front faces 22, refining surfaces 5, 9 with blade bars 16 and blade grooves 17 therebetween, the blade bars 16 and blade grooves 17 extending along the front faces 22 of the segments 4, 8. The blade bars 16 and blade grooves 17 have a longitudinal direction and a width or transverse direction substantially intersecting the longitudinal direction. The blade bars 16 are intended to macerate and refine the material to be refined, and the blade grooves 17 are intended to carry the material forward along the refining surfaces 5, 9.

[0025] The blade segments 4, 8 include inner or first or feed edges 18 that are oriented toward the first end 12' of the refining chamber 12, i.e., toward the end of the refining element 3, 6 having the smaller diameter. The fibrous material to be refined is fed or supplied over the first edges 18 to the refining surfaces 5, 9.

[0026] The blade segments 4, 8 further include outer or second or discharge edges 19 oriented toward the second end 12″ of the refining chamber 12, i.e., toward the end of the refining element 3, 6 having a larger diameter. The refined fiber material is discharged from the refining surfaces 5, 9 over the second edges 19.

[0027] In conical and cylindrical refiners, the inner edges 18 of the blade segments 4, 8 define the axially inner ends 18 of the blade segments 4, 8, and the outer edges 19 of the blade segments 4, 8 define the axially outer ends 19 of the blade segments 4, 8, with the direction from the axially inner ends 18 to the axially outer ends 19 defining the axial direction of the blade segments 4, 8. In disc refiners, the inner edges of the blade segments are the radially inner ends of the blade segments, and the outer edges of the blade segments are the radially outer ends of the blade segments, with the direction from the radially inner ends to the radially outer ends defining the radial direction of the blade segments. In other words, the blade segments 4, 8 have a longitudinal direction extending between the inner edges 18 and the outer edges 19, as shown in FIG. 2, and the diagrammatic arrow LD extends from the inner edges 18 to the outer edges 19 of the blade segments 4, 8. When the blade segments 4, 8 are installed in a refiner, the longitudinal direction LD of the blade segments 4, 8 or their projection is substantially parallel to the axial direction of the refiner in the case of cylindrical and conical refiners, and substantially parallel to the radial direction of the refiner in the case of disc refiners. Thus, for blade segments 4, 8 intended for conical and cylindrical refiners, the longitudinal direction LD of the blade segments 4, 8 corresponds to the aforementioned axial direction of the blade segments 4, 8, and for blade segments 4, 8 intended for disc refiners, the longitudinal direction LD of the blade segments 4, 8 corresponds to the aforementioned radial direction of the blade segments 4, 8.

[0028] The blade segments 4, 8 further include a first or leading side edge 20 that extends from the inner edge 18 of the blade segment 4, 8 to the outer edge 19 of the blade segment 4, 8. The first side edge 20 is the edge of the blade segment 4, 8 that first contacts the edge of the counter blade segment during rotation of the rotor 6. Thus, in the rotor 6, it provides the side edge of the blade segment 8 that should be oriented toward the intended direction of rotation RD of the rotor 6, and in the stator 3, it provides the side edge of the blade segment 4 that should be oriented in the opposite direction relative to the intended direction of rotation RD of the rotor 6.

[0029] The blade segments 4, 8 further include second or trailing side edges 21 opposite the first side edges 20 and extending from the inner edge 18 of the blade segments 4, 8 to the outer edge 19 of the blade segments 4, 8. The second side edges 21 are then the edges of the blade segments 4, 8 that last contact the edges of the counter blade segments during rotation of the rotor 6. Thus, in the rotor 6, the side edges of the blade segments 8 are provided oriented in an opposite direction to the intended direction of rotation RD of the rotor 6, and in the stator 3, they are provided oriented toward the intended direction of rotation RD of the rotor 6. In the embodiment of FIG. 2, the first and second side edges 20, 21 are straight, but they can also be curved. The direction of the blade segments 4, 8 extending between the first and second side edges 20, 21 perpendicular to the longitudinal direction LD of the blade segments 4, 8 is the circumferential direction CD of the blade segments 4, 8. Thus, the circumferential direction CD of the blade segments 4,8 forms a normal N to the longitudinal direction LD of the blade segments 4,8.

[0030] The inner edge 18 and outer edge 19 together with the first side edge 20 and second side edge 21 define the perimeter of the blade segments 4,8.

[0031] The refining surfaces 5, 9 of the blade segments 4, 8 further include a number of equalization pockets 23, i.e., at least one equalization pocket 23 or more than one equalization pocket 23 extending along the refining surfaces 5, 9 of the blade segments 4, 8. The equalization pocket 23 is a portion of the refining surface 5, 9 where the flow of fibrous material along the refining surface 5, 9 is allowed to equalize or balance before advancing again along the refining surface 5, 9. The equalization pocket 23 has a first end 23' and a second end 23", and thus the equalization pocket 23 has a longitudinal direction or elongation direction in the direction between the first end 23' and the second end 23", the longitudinal direction of the equalization pocket 23 being indicated schematically in FIG. 2 by the line designated by reference numeral 231. The equalization pocket 23 begins at a first end 23' from a blade bar 16, extends across one or more blade bars 16 and its / their adjacent blade grooves 17 intersecting all of them, and terminates at a second end 23" to another blade bar 16. The starting or ending point of the equalization pocket 23 may be located on adjacent blade segments 4, 8.

[0032] The equalization pocket 23 is arranged along its longitudinal direction 231 to intersect with multiple blade bars 16 and multiple blade grooves 17, i.e., to surround at least one blade bar 16 or more than one blade bar 16 and multiple blade bars 16 and / or each remaining blade groove 17 in multiple blade bars 16. Thus, at a minimum, the equalization pocket 23 is arranged to intersect with one blade bar 16, thereby extending beyond a single blade bar 16 and the blade grooves 17 on both sides of the blade bar 16. However, typically, the equalization pocket 23 is arranged to intersect with at least two blade bars 16, thereby extending beyond at least two blade bars 16 and the blade grooves 17 between at least two blade bars 16, as well as the blade groove 17 surrounding the outermost blade bar 16 in the extension direction 231 of the equalization pocket 23. In the embodiment of Figure 2, the equalization pockets 23 are positioned to extend across four to seven blade bars 16, depending on the location of each equalization pocket 23 on the refining surfaces 5, 9 of the blade segments 4, 8. However, the number of blade bars 16 intersected by a pocket 23 can be from one blade bar 16 to any number in such a way that at least one pocket 23 is formed between the side edges 20, 21 of the blade segments 4, 8.

[0033] The effect of the at least one equalization pocket 23 is to provide a deliberate or purposeful break in the otherwise substantially continuous path or run of the at least one blade bar 16 and respective blade groove 17, whereby at least a portion of the flow of fibrous material to be refined on the refining surfaces 5, 9 from the direction of the first edge 18 of the blade segments 4, 8 towards the second edge 19 of the blade segments 4, 8 is interrupted and allowed to equalize or balance and recombine in the equalization pocket 23 before proceeding further towards the second edge 19 of the blade segments 4, 8. The angle α between the longitudinal direction 23l of the equalization pocket 23 and the axial or radial direction A of the blade segments 4, 823l is greater than 0 degrees but less than 90 degrees, preferably between 10 and 80 degrees, and more preferably between 30 and 80 degrees. Thus, the longitudinal direction 231 of the equalization pocket 23 is disposed to deviate from the axial / radial direction A of the blade segments 4, 8 and from a direction normal N to the axial / radial direction A of the blade segments 4, 8. The axial / radial direction A of the blade segments 4, 8 and the direction normal N to the axial / radial direction A of the blade segments 4, 8 are shown schematically in FIG. 2.

[0034] In the embodiment of FIG. 2 , each equalizing pocket 23 is positioned to intersect with its respective blade bar 16 and blade groove 17 at an angle of approximately 90 degrees. Thus, in the embodiment of FIG. 2 , the intersection angle between the longitudinal direction 231 of the equalizing pocket 23 and the blade bar 16 is approximately 90 degrees. Generally, the intersection angle between the longitudinal direction of the equalizing pocket 23 and the blade bar 16 may be 90±50 degrees. The effect of this angle range is that the extension direction of the equalizing pocket 23 deviates from the direction of the blade bar 16 and blade groove 17 to an extent that ensures that at least a portion of the flow of fibrous material is intercepted, stabilizes in the equalizing pocket 23 before proceeding further toward the second edge 19 of the blade segment 4, 8, and then recombines, thereby allowing for better handling of shives.

[0035] Thus, the longitudinal direction 23l of the equalization pocket 23 is arranged to deviate from the direction of the blade bar 16 and from the axial / radial direction A of the blade segments 4, 8 and their normal N.

[0036] The refining surfaces 5, 9 of the blade segments 4, 8 of FIG. 2 include three series 24 of consecutively and substantially correspondingly oriented equalizing pockets 23, with the ends 23', 23" of consecutively arranged equalizing pockets 23 in a series 24 of equalizing pockets 23 separated from one another by a single blade bar 16. Each series 24 of consecutively and substantially correspondingly oriented equalizing pockets 23 is positioned to extend across at least a portion of the refining surfaces 5, 9 from the direction of the second side edge 21 of the blade segments 4, 8 toward the first side edge 20 of the blade segments 4, 8.

[0037] Generally, the refining surfaces 5, 9 of the blade segments 4, 8 may include at least one series 24 of at least two consecutively and substantially correspondingly oriented equalizing pockets 23, each series 24 of equalizing pockets 23 arranged to extend across at least a portion of the refining surfaces 5, 9, and the ends 23', 23" of the at least two consecutively arranged equalizing pockets 23 are separated from each other by at least one blade bar 16. For the first or last pocket 23 of a pocket series 24, the pocket 23 closest to the side edges 20, 21, the separating blade bar 16 may be, and typically is, located on the adjacent blade segment 4, 8.

[0038] At least one series 24 of equalizing pockets 23 arranged to extend across at least a portion of the refining surface 5,9 of the blade segments 4,8 provides an equalizing or balancing effect of the flow of fibrous material so that it effectively occurs over a larger portion of the refining surface 5,9 of the blade segments 4,8 compared to equalizing pockets 23 distributed at random locations on the refining surface 5,9, or in some cases completely separated.

[0039] The number of series of pockets 23 can be several. Although there are three parallel-oriented series 24 in Figure 2, the mutual orientation of the series can also be non-parallel, for example, such that the series 24 closer to the outer edge 19 can be oriented at a steeper crossing angle relative to the series 24 located more inwardly.

[0040] The effect of the configuration in which the ends 23', 23" of consecutively arranged equalizing pockets 23 in a series 24 of equalizing pockets 23 are separated from one another by at least one blade bar 16 is that the flow of fibrous material along the equalizing pockets 23 in at least a partial circumferential direction of the blade segments 4, 8 is then interrupted at some point, i.e., excessive flow of fibrous material in at least a partial circumferential direction of the blade segments 4, 8 is not allowed, and the fibrous material is thereby forced to flow again mainly towards the discharge edges 19 of the blade segments 4, 8, thereby also preventing clogging of the refining surfaces 5, 9 of the blade segments 4, 8. Thus, at least one blade bar 16 between two consecutive equalizing pockets 23 provides an element that separates two consecutive equalizing pockets 23 from one another in the longitudinal direction of the series 24 of equalizing pockets 23, or that terminates the equalizing pockets 23 at their respective ends 23', 23".

[0041] Further, with reference to the embodiment of FIG. 2 , the series 24 of equalization pockets 23 are arranged in the refining surfaces 5, 9 at an angle that deviates from the normal N to the axial / radial direction A of the blade segments 4, 8. Thus, instead of being arranged at the same axial / radial position, the pockets 23 are more uniformly distributed over the axial / radial length of the refining surfaces. Generally, according to one embodiment, at least one series of at least two equalization pockets are arranged in the refining surfaces at an angle that deviates from the normal N to the axial / radial direction of the blade elements. This has several advantages: the flow of material toward the discharge edge 19 is not impeded but maintained or improved, and wear of the blade elements is more uniform. Furthermore, pressure fluctuations that sometimes occur during refiner operation may be avoided.

[0042] The disclosed blade segments 4, 8 have a specific intended orientation for their installation in the refiner 1, in which the blade bars 16 and blade grooves 17 are disposed at an angle relative to the intended direction of rotation RD of the rotor 6 of the refiner 1 to promote the flow of fibrous material toward the second edges 19 of the blade segments 4, 8. At the same time, the at least one equalization pocket 23 is disposed at an angle relative to the intended direction of rotation RD of the rotor 6 of the refiner 1 to resist the flow of fibrous material toward the second edges 19 of the blade segments 4, 8. In the implementation of the embodiment of FIG. 2, this is achieved by the angle α between the blade bars 16 and a normal N to the axial or radial direction A of the blade segments 4, 8. 16 Or by positioning the blade bar 16 and respective blade groove 17 so that the tangent of the blade bar 16 is greater than 90 degrees on the side of the leading edge 20. In other words, the blade bars / grooves 16, 17 and pockets 23 or series 24 of pockets 23 are inclined to each other in opposite directions relative to direction A, which is equal in the axial direction in the case of a conical / cylindrical refiner and equal in the radial direction in the case of a disc refiner.

[0043] By positioning the blade bars and respective blade grooves at an angle relative to the intended direction of rotation RD of the refiner rotor that promotes the flow of fibrous material toward the second edge of the blade element, it is ensured that the fibrous material to be refined has a general flow direction toward the discharge edge of the blade element, thereby preventing blocking of the refining surface by the fibrous material to be refined. However, by positioning at least one equalization pocket relative to the intended direction of rotation RD of the refiner rotor at an angle that opposes the flow of fibrous material toward the discharge edge of the blade element, such effect, however, is to immediately interrupt the flow of material toward the discharge edge of the blade element and expose at least a portion of the fibrous material flow to allow it to equalize or balance before proceeding further to the discharge edge of the blade element.

[0044] According to one embodiment of the equalization pocket 23, the volume of the equalization pocket 23 is arranged to decrease from the first end 23' of the equalization pocket 23 toward the second end 23" of the equalization pocket 23. The decreasing volume of the equalization pocket 23 from the first end 23' toward the second end 23" causes the fibrous material entering the equalization pocket 23 to be equalized or balanced within the equalization pocket 23 before being discharged from the equalization pocket 23 toward the discharge edge 19 of the blade segment 4, 8.

[0045] The volume of the equalization pocket 23 decreasing from the first end 23' toward the second end 23" may be achieved by arranging at least one of the width and depth of the equalization pocket 23 to decrease from the first end 23' of the equalization pocket 23 toward the second end 23" of the equalization pocket 23. In other words, the width and / or depth of the equalization pocket 23 may be configured to decrease from the first end 23' of the equalization pocket 23 toward its second end 23".

[0046] The width of the equalization pocket 23 refers to a measurement (scale) of the equalization pocket 23 that is substantially intersecting the direction between the first end 23′ and the second end 23″ of the equalization pocket 23 and may be determined as the distance between an end 16a′ of a blade bar 16a that extends from the direction of the first edge 18 of the blade segment 4, 8 toward the equalization pocket 23 in question, and an end 16b′ of another blade bar 16b that extends from the equalization pocket 23 in question at least partially toward the second edge 19 of the blade segment 4, 8 and is substantially opposite the blade bar 16a first mentioned herein ( FIG. 3 ).

[0047] The depth of the equalization pocket 23 may be determined as the vertical distance between the bottom of the equalization pocket 23 and the level of the top surface of the blade bar 16 .

[0048] According to one embodiment of the equalization pocket 23, at least one of the width and depth of the equalization pocket 23 is arranged to decrease dynamically from the first end 23' of the equalization pocket 23 toward the second end 23" of the equalization pocket 23. In other words, the width and / or depth of the equalization pocket 23 is arranged to decrease dynamically, i.e., in a substantially continuous manner, from the first end 23' of the equalization pocket 23 toward the second end 23" of the equalization pocket 23, whereby the fibrous material entering the equalization pocket 23 is forced to flow further away from the equalization pocket 23 toward the discharge edge 19 of the blade segment 4, 8 in a substantially uniform manner without causing undesirable turbulence in the flow of the fibrous material. A gradual decrease in the width and / or depth of the equalization pocket 23 is, of course, possible, but is less preferred.

[0049] Referring again to the embodiment of FIG. 2 , the equalization pockets 23 are arranged on the refining surfaces 5, 9 of the blade segments 4, 8 at an angle to the first and second edges 18, 19 of the blade segments 4, 8, such that the first ends 23′ of the equalization pockets 23 are closer to the first edges 18 of the blade segments 4, 8 than the second ends 23″ of the equalization pockets 23. This embodiment, particularly in conjunction with the decreasing volume of the equalization pockets 23 toward the second ends 23″ of the equalization pockets 23, has the effect that fibrous material entering the equalization pockets 23 is forced to continue flowing toward the outer edges 19 of the blade segments 4, 8. This type of alignment of the equalization pockets 23 also leads to an alignment of the series 24 of equalization pockets 23, with one end of the series 24 of equalization pockets 23 closer to the first edges 18 of the blade segments 4, 8 and the other end of the series 24 of equalization pockets 23 closer to the second edges 19 of the blade segments 4, 8. Thus, the series 24 of equalization pockets 23 are aligned or oriented at least partially toward the second edges 19 of the blade segments 4,8.

[0050] 2, the volume of the equalization pockets 23 that remain closer to the second edges 19 of the blade segments 4, 8 is arranged to be smaller than the volume of the equalization pockets 23 that remain closer to the first edges 18 of the blade segments 4, 8. Generally, according to one embodiment of the blade element, the volume of at least one equalization pocket that remains closer to the second edge of the blade element is configured to be smaller than the volume of at least one other equalization pocket that remains closer to the first edge of the blade element. This has the effect that the residence time of the fibrous material that enters the equalization pockets 23 decreases toward the discharge end 12" of the refining chamber 12, and the flow of fibrous material toward the discharge end 12" of the refining chamber 12 is thereby more effective near the discharge end 12" of the refining chamber 12.

[0051] According to one embodiment of the blade segments 4, 8, and with particular reference to FIG. 3, the width W of the blade groove 17 extending from the equalization pocket 23 at least partially toward the second edge 19 of the blade segments 4, 8 is 17 are arranged to increase from a first end 23" of the equalizing pocket 23 toward a second end 23" of the equalizing pocket 23. Generally speaking, the equalizing pocket 23 has a first end 23' and a second end 23", and has a blade groove 17 width W that extends from at least one equalizing pocket 23 toward at least partially the second edges 19 of the blade segments 4, 8, i.e., of those grooves 17 that intersect the pocket 23. 17 may be determined to be arranged to increase from the first end 23' of the equalization pocket 23 to the second end 23'' of the equalization pocket 23. The width W of the blade groove 17 17are arranged in a substantially continuously increasing manner in the equalizing pocket 23, with the blade grooves 17 at the first end 23' of the equalizing pocket 23 being the narrowest and the blade grooves 17 at the second end 23" of the equalizing pocket 23 being the widest, with each blade groove 17 closer to the second end 23" of the equalizing pocket 23 being at least slightly wider than the blade grooves 17 closer to the first end 23' of the equalizing pocket 23. The different widths of the grooves 17 allow fibers / debris / particles of different sizes to be redistributed into grooves 17 corresponding to their sizes when the material flow is stable in the equalizing pocket 23. Widening the grooves 17 in this order, i.e., from the first end 23' to the second end 23", is beneficial to ensure a smooth flow of particles. In the reverse order, the widest grooves would be filled with smaller particles, and larger sized debris would not be able to find an outlet that would accommodate them. The width W of the blade grooves 17 at the first end 23' of the equalizing pocket 23 17 may be, for example, 1 to 5 mm, and the width W of the blade groove 17 at the second end 23″ of the equalization pocket 23 17 may be, for example, 5 to 10 mm.

[0052] The width of the blade groove 17, which increases toward the second end 23" of the equalization pocket 23, ensures that larger-sized debris that enters the equalization pocket 23 can also exit the equalization pocket 23, thereby defibrating and refining the fibers, without obstructing the refining surfaces 5, 9. This embodiment, particularly in conjunction with the volume of the equalization pocket 23, which decreases toward the second end 23" of the equalization pocket 23, effectively ensures that the pulp flow is forced to remix, thereby forcing the debris-containing material to exit the equalization pocket 23 and flow toward the outer edges 19 of the blade elements 4, 8.

[0053] It will be obvious to those skilled in the art that with the advancement of technology, the concept of the present invention can be implemented in various ways. The present invention and its embodiments are not limited to the examples described above, but may vary within the scope of the claims.

Claims

1. 1. A blade element for a refiner for refining fibrous material, comprising: a first edge to be directed toward the feeding of the fiber material to be refined and a second edge to be directed toward the discharge of the refined fiber material; a refining surface including blade bars and blade grooves between the blade bars; the refining surface includes at least one equalizing pocket extending along the refining surface of the blade element and intersecting multiple blade bars and multiple blade grooves to equalize the flow of the fibrous material along the refining surface, the equalizing pocket starting at a first end from a blade bar, extending across one or more blade bars and / or their adjacent blade grooves intersecting all of them, and terminating at a second end to another blade bar; The longitudinal direction of the equalization pocket is arranged to deviate from the direction of the blade bar, from the longitudinal direction of the blade element, and from a direction normal to the longitudinal direction of the blade element; a volume of the equalization pocket configured to decrease from a first end of the equalization pocket toward a second end of the equalization pocket; Blade element.

2. 2. The blade element of claim 1, wherein the refining surface includes at least one series of at least two consecutively and substantially correspondingly oriented equalizing pockets, each series of equalizing pockets configured to extend across at least a portion of the refining surface, and wherein ends of the at least two consecutively arranged equalizing pockets in each series of equalizing pockets are separated from one another by at least one blade bar.

3. 3. The blade element of claim 2, wherein said series of at least two equalizing pockets are disposed on said refining surface at an angle that deviates from a normal to the longitudinal direction of said blade element.

4. 4. The blade element of claim 1, wherein the blade element has a particular intended orientation for mounting the blade element within the refiner, in which the blade bar and blade groove are positioned at an angle relative to the intended direction of rotation of the refiner rotor that promotes the flow of the fibrous material toward the second edge of the blade element.

5. 2. The blade element of claim 1, wherein at least one of a width and a depth of the equalization pocket is configured to decrease from the first end of the equalization pocket toward the second end of the equalization pocket so as to decrease the volume of the equalization pocket from the first end of the equalization pocket toward the second end of the equalization pocket.

6. 6. The blade element of claim 5, wherein at least one of the width and the depth of the equalizing pocket is configured to dynamically decrease from the first end of the equalizing pocket toward the second end of the equalizing pocket.

7. 7. A blade element according to claim 1, wherein the equalization pocket is positioned at an angle relative to the first and second edges of the blade element such that the first end of the equalization pocket is closer to the first edge of the blade element than the second end of the equalization pocket.

8. 8. A blade element according to claim 1, characterized in that the volume of at least one equalization pocket that remains closer to the second edge of the blade element is configured to be smaller than the volume of at least one other equalization pocket that remains closer to the first edge of the blade element.

9. the equalization pocket has a first end and a second end; a width of the blade groove extending from the at least one equalization pocket at least partially toward the second edge of the blade element increases in a direction from the first end of the equalization pocket toward the second end of the equalization pocket. A blade element according to any one of claims 1 to 8.

10. A blade element according to any one of claims 1 to 9, characterized in that it is a blade segment intended to provide a part of the complete refining surface of a refining element of the refiner.

11. A refiner for refining fibrous material, characterized in that it comprises at least one blade element according to any one of claims 1 to 10.

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