Apparatus and method for treating wood fibers

Abstract

To provide an apparatus and a method for refining wood fibers and for breaking up fiber bundles.SOLUTION: A refining member comprising a refining body having refining surfaces comprising a first refiner bar side 28B and a second refiner bar side 26B separated by a first refiner groove side wall and a second refiner groove side wall. 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 respective first and second heights 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, and the second height is at least about 0. 35mm less than the first height.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] Related Applications This application is a continuation-in-part of U.S. patent application Ser. No. 15 / 860,055 (Attorney Docket No. TEC-119945-US), filed January 2, 2018, which is related to U.S. patent application Ser. No. 15 / 860,006 (Attorney Docket No. TEC-120257-US), filed January 2, 2018. This application also claims dual priority to U.S. patent application Ser. No. 15 / 860,006.

[0002] The present disclosure relates generally to processing wood fibers in a refiner, and more particularly to an apparatus and method for refining wood fibers and breaking down fiber bundles. [Background technology]

[0003] Disc-type refiners have traditionally been used to process wood fibers in paper product-making processes. Such refiners include first and second refining elements having a refining space therebetween. Each of the first and second refining elements includes a plurality of refiner bars separated by refiner grooves, the refiner bars defining cutting surfaces for cutting the wood fibers. During operation, at least one of the first and second refining elements is rotated relative to the other, and the rotation of the refiner bar cutting surfaces cuts the wood fibers being processed in the refiner. Once the wood fibers are processed in the refiner, the processed wood fibers can be further processed in a subsequent paper product-making process to produce a paper product. In some cases, the wood fibers can undergo additional processing, such as in a separate tickler refiner or deflaker. As is known in the art, conical refiners operate similarly, except that the refining elements are positioned on a conical surface rather than on a disk. Summary of the Invention [Means for solving the problem]

[0004] According to a first aspect of the present invention, there is provided a refining member for a pulp refiner, the refining member comprising first refiner bars separated by first refiner grooves and extending from a first radially inward position to a first radially outward position on the refining surface, and second refiner bars separated by second refiner grooves and extending from a second radially inward position to a second radially outward position on the refining surface. The refiner body includes a refining surface including a first refiner bar and a second refiner bar having a second radially outward position, the second radially outward position being closer to an outermost part of the refiner body than the first radially outward position. The first refiner bar has a first height extending upward from a floor of an adjacent first refiner groove section, and the second refiner bar has a second height extending upward from a floor of an adjacent second refiner groove section. The second height is a minimum height of the second refiner bar and is spaced apart from the second radially inward position, the second height being at least about 0.35 mm less than the first height. The first refiner bar is adapted to refine wood fibers, and the second refiner bar is adapted to break down fiber bundles.

[0005] The minimum height of the second refiner bar can be adjacent to the second radially outward location. The first height can be substantially constant along the longitudinal length of the first refiner bar.

[0006] The first height can be about 4.0 mm to about 10.0 mm. The second height can be about 0.35 mm to about 7.0 mm less than the first height, or about 0.7 mm to about 7.0 mm less than the first height.

[0007] The second refiner bars can be integral with the first refiner bars such that the second refiner bars extend from a first radially outward position to a second radially outward position, and each of the second refiner bars can be substantially continuously downwardly sloped along at least a portion of each second refiner bar extending between the first radially outward position and the second radially outward position.

[0008] At least a portion of the first refiner flute may be equipped with a dam. The first height of the first refiner bar may include a first maximum height, the second refiner bar may include a second maximum height extending upward from the floor of the adjacent second refiner groove portion, and the radially outer portion of each first refiner bar may include a step down from the first maximum height to the second maximum height, and the second maximum height may be at least about 1.5 mm smaller than the first maximum height.

[0009] The refining element may further include third refiner bars separated by third refiner grooves and fourth refiner bars separated by fourth refiner grooves. Each of the third refiner bars may extend to a third radially outward position on the refining surface, and each of the fourth refiner bars may extend to a fourth radially outward position on the refining surface that is closer to the outermost part of the refining body than the third radially outward position. The third refiner bars may have a third height extending upward from the floor of the adjacent third refiner groove, and the fourth refiner bars may have a fourth height extending upward from the floor of the adjacent fourth refiner groove. The fourth height may be the minimum height of the fourth refiner bar and may be adjacent to the fourth radially outward position. The fourth height can be at least about 0.35 mm less than the third height. The third refiner bar can be adapted to refine wood fibers, and the fourth refiner bar can be adapted to break down fiber bundles.

[0010] The third refiner bar may be integral with the second refiner bar such that the third refiner bar extends from the second radially outward position to the third radially outward position, and the fourth refiner bar may be integral with the third refiner bar such that the fourth refiner bar extends from the third radially outward position to the fourth radially outward position.

[0011] The third height of the third refiner bar may include a third maximum height, the fourth refiner bar may include a fourth maximum height extending upward from the floor of the adjacent fourth refiner groove section, the radially outer portion of each third refiner bar may include a step down from the third maximum height to the fourth maximum height, and the fourth maximum height may be at least about 1.5 mm smaller than the third maximum height.

[0012] According to a second aspect of the present disclosure, there is provided a pulp refiner including a frame, at least a first pair of refining members, and a rotor, the refining members including a first refining member associated with the frame and including a first refining body, and a second refining member associated with the frame and including a second refining body. The first refining body includes a first refining surface, the first refining surface including first refiner bars separated by first refiner grooves and extending from a first radially inward position on the refining surface to a first radially outward position on the refining surface, and second refiner bars separated by second refiner grooves and extending from a second radially inward position on the refining surface to a second radially outward position on the refining surface, the second radially outward position being closer to an outermost part of the refining body than the first radially outward position. The first refiner bars have a first height extending upward from the floor of the adjacent first groove, and the second refiner bars have a second height extending upward from the floor of the adjacent second groove. The second height is a minimum height of the second refiner bar and is spaced apart from the second radially inward position. The second height is at least about 0.35 mm less than the first height. The second refining element includes a second refining surface including second member refiner bars separated by second member refiner grooves. The first refining element is spaced apart from the second refining element to define a refining space therebetween, and at least a portion of the second member refiner bar is positioned directly opposite the second member refiner bar to define a gap between the portion of the second member refiner bar and the second member refiner bar. A rotor is coupled to one of the first refining element or the second refining element such that rotation of the rotor effects movement of one of the first refining element or the second refining element relative to the other.When a wood pulp slurry containing wood fibers is supplied to the frame, the wood pulp slurry passes through the refining space so that a significant number of wood fibers in the wood pulp slurry are refined and multiple wood fiber bundles in the wood pulp slurry are separated.

[0013] The minimum height of the second refiner bar can be adjacent to the second radially outward location. The first height can be substantially constant along the longitudinal length of the first refiner bar.

[0014] The second height may be at least about 0.7 mm less than the first height. The first height of the first refiner bar may include a first maximum height, The second refiner bar may include a second maximum height extending upward from the floor of the adjacent second refiner groove section, and the radially outer portion of each first refiner bar may include a step-down from the first maximum height to the second maximum height, and the second maximum height may be at least about 1.5 mm smaller than the first maximum height.

[0015] The second member refiner bar may include a first refiner bar element extending from a first radially inward position on the second refining surface to a first radially outward position, and a second refiner bar element located closer to the outermost part of the second refining body than the first radially outward position and extending to a second radially outward position on the second refining surface. The first refiner bar element may have a first bar height extending upward from the floor of the adjacent groove, and the second refiner bar element may have a second bar height extending upward from the floor of the adjacent groove. The second bar height may be a minimum height of the second refiner bar element and may be adjacent to the second radially outward position. The second bar height may be at least about 0.35 mm less than the first bar height.

[0016] According to a third aspect of the present disclosure, a method for processing wood fibers is provided. The method includes providing a refiner including at least a first pair of refining members. The refining members include a first refining member including a first refining body and a second refining member including a second refining body. The first refining body includes a first refining surface, the first refining surface including first refiner bars separated by first refiner grooves and having a first height extending upward from the floor of an adjacent first refiner groove, and a second refiner bar separated by second refiner grooves and having a second height extending upward from the floor of an adjacent second refiner groove. The second refining body includes a second refining surface, the second refining surface including second member refiner bars separated by second member refiner grooves. The first refining element is spaced apart from the second refining element to define a refining space therebetween, and at least a portion of the second element refiner bar is positioned directly opposite the second element refiner bar to define a gap between the portion of the second element refiner bar and the second element refiner bar. The method further includes rotating at least one of the first refining element or the second refining element so that the first and second refining elements move relative to one another, supplying a slurry of wood pulp containing wood fibers to the refiner such that the slurry passes through the refining space, and applying axial pressure to at least one of the first refining element or the second refining element as the slurry is supplied. A gap between a portion of the second member refiner bar and the second refiner bar increases along at least one section of the second refiner bar in a direction extending from a first radially inward position to a first radially outward position on the first refining surface, and at least a portion of the wood fiber bundles passing through the gap are separated.

[0017] The second height can be a minimum height of the second refiner bar and can be adjacent to the first radially outward location. The second height can be at least about 0.35 mm less than the first height.

[0018] While the specification concludes with claims particularly pointing out and distinctly claiming the invention, the present invention will be better understood from the following description taken in conjunction with the accompanying drawings. As such, it is contemplated that in the drawings, like reference numbers identify like elements. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a schematic partial cross-sectional view of a disc refiner. [Figure 2] FIG. 2 is a plan view of the first refining body. [Figure 3] FIG. 10 is a plan view of the second refining body. [Figure 4A] FIG. 3 is a plan view of a section of the refining surface of the first refining body of FIG. 2. [Figure 4B] FIG. 3 is a plan view of a section of the refining surface of the first refining body of FIG. 2. [Figure 5] Figure 5A is a plan view of a section of the refining surface of the second refining body of Figure 3. Figure 5B is a plan view of a section of the refining surface of the second refining body of Figure 3. [Figure 6] Figure 6A is a partial cross-sectional view of the refining body taken along line 6A-6A in Figures 4A and 5A, and Figure 6B is a partial cross-sectional view of the refining body taken along line 6B-6B in Figures 4B and 5B. [Figure 7] 7 is a partial cross-sectional view taken along line 7-7 in FIGS. 4A, 4B, 5A, and 5B. FIG. [Figure 8]A partial cross-sectional view of a refiner bar on a first refining body portion positioned spaced apart above a corresponding refiner bar on a second refining body portion. [Figure 9] A partial cross-sectional view of a refiner bar on a first refining body portion positioned spaced apart above a corresponding refiner bar on a second refining body portion. [Figure 10] FIG. 1 is a plan view of a portion of a first refining body including a plurality of radially extending pie-shaped segments. [Figure 11] FIG. 10 is a plan view of a portion of a second refining body including a plurality of radially extending pie-shaped segments. [Figure 12] Figure 12A is a partial cross-sectional view of a refiner bar from the pie-shaped segment of Figures 10 and 11, with one refining body positioned above another refining body in a spaced-apart relationship. Figure 12B is a partial cross-sectional view of a refiner bar from the pie-shaped segment of Figures 10 and 11, with one refining body positioned above another refining body in a spaced-apart relationship. [Figure 13] FIG. 1 is a plan view of a first refining body including teeth. [Figure 14] FIG. 10 is a plan view of a second refining body including teeth. [Figure 15] FIG. 14 is a plan view of a section of the refining surface of the first refining body of FIG. 13. [Figure 16] FIG. 15 is a plan view of a section of the refining surface of the second refining body of FIG. 14. [Figure 17] A partial cross-sectional view of refiner bars and teeth on a first refining body portion positioned spaced apart above a second refining body portion including refiner bars and teeth. [Figure 18] 1 is a flow chart illustrating an exemplary method for treating wood fibers. [Figure 19A] FIG. 6B is a partial cross-sectional view of the refining body similar to FIG. 6A. [Figure 19B] FIG. 6C is a partial cross-sectional view of the refining body similar to FIG. 6B. [Figure 20] 1 is a flow chart illustrating another exemplary method for treating wood fibers. DETAILED DESCRIPTION OF THE INVENTION

[0020] In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration, and not by way of limitation, specific preferred embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and changes may be made without departing from the spirit and scope of the invention.

[0021] FIG. 1 illustrates a schematic, partial cross-sectional view of a disc refiner 10 according to the present disclosure. The disc refiner 10 includes a housing with a first housing section 12 and a second housing section 14, which may be bolted or otherwise fixedly attached together. The housing sections 12, 14 define an inlet section 16, an outlet section 18, and a refiner internal cavity 64, which contains one or more pairs of refining elements. The embodiment shown in FIG. 1 is a double-disc refiner 10 including two pairs of refining elements, e.g., a first refining element 20 paired with a second refining element 30, and a third refining element 40 paired with a fourth refining element 50. The first refining member 20 includes a first refining body 22 with a first refining surface 24, and the second refining member 30 includes a second refining body 32 with a second refining surface 34. The third refining member 40 includes a third refining body 42 and a third refining surface 44, and the fourth refining member 50 includes a fourth refining body 52 and a fourth refining surface 54. Each of the refining members 20, 30, 40, 50 is associated with a main support frame, which includes a fixed support frame 66 fixed to the first housing section 12 and a movable support frame 68, as described herein.

[0022] The first, second, third, and fourth refining body portions 22, 32, 42, 52 can be generally disk-shaped with substantially identical outer diameters (see FIGS. 2 and 3). The first and second refining members 20, 30 are arranged such that the first refining surface 24 faces the second refining surface 34, and the third and fourth refining members 40, 50 are arranged such that the third refining surface 44 faces the fourth refining surface 54. The first refining member 20 is spaced apart from the second refining member 30, defining a first refining space 60 between their respective refining surfaces 24, 34. The third refining member 40 is spaced apart from the fourth refining member 50, defining a second refining space 62 between their respective refining surfaces 44, 54. The disc refiner 10 may have a structure similar to that illustrated in US Patent Application Publication No. 2006 / 0037728A1, the disclosure of which is incorporated herein by reference.

[0023] In the embodiment shown in FIG. 1 , the first and fourth refining members 20, 50 are stationary, and the second and third refining members 30, 40 rotate relative to the first and fourth refining members 20, 50. The first refining member 20 may be secured to a support frame 66 by bolts or other suitable fasteners (not shown). The second and third refining members 30, 40 may be mounted on a support 70 that is coupled to a rotatable shaft 72 and extends radially outward from the rotatable shaft 72. The support 70 is coupled to the shaft 72 for rotation therewith and is axially movable along the shaft 72. The shaft 72 is driven by a first motor 74, which drives the support 70. The first and second refining members 30, 40 and the second and third refining members 30, 40 rotate together with the shaft 72 during operation of the disc refiner 10. The shaft 72 has a central axis 72A that is generally coaxial with the axes of rotation of the second and third refining members 30, 40. The shaft 72 may be rotatably mounted to the stationary support frame 66 such that the first and second refining members 30, 40 are associated with the main support frame. The support 70 may be axially movable along the shaft 72, e.g., substantially along the central axis 72A, relative to the first and fourth refining members 20, 50, as described herein. The fourth refining member 50 may be secured to the movable support frame 68 by bolts or other suitable fasteners (not shown). Thus, the support 70 and shaft 72 can define a rotor associated with the main support frame, such that the second and third refining members can define rotating rotor members, and the first and fourth refining members 20, 50 can define non-rotating stator members. Rotation of the rotor effects movement of the second and third refining members 30, 40 relative to the first and fourth refining members 20, 50, respectively.

[0024] The movable support frame 68 may be mounted within the second housing section 14 and coupled to a second motor 76, which may include a reversible electric motor fixed in place. The second motor 76 moves the movable support frame 68 in a substantially horizontal (i.e., axial) direction indicated by arrow A. The refiner 10 may include, for example, a jackscrew (not shown) coupled to the second motor 76 and the movable support frame 68, which may rotate the jackscrew to move the movable support frame 68, to which, for example, the fourth refining member 50 is attached. This movement adjusts the size of the gap, i.e., the size of the first and second refining spaces 60, 62, defined between the first and second refining members 20, 30 and the third and fourth refining members 40, 50 (see also Figures 8 and 9). In other embodiments (not shown), control of the gap size may be achieved by one or more magnetic bearings. The magnetic bearings that control the axial position of shaft 72 may be used to control the position of a rotating rotor member fixed to shaft 72. Magnetic bearings may be used to control the axial position of one or more additional moving sections of the main support frame (i.e., movable support frame 68) to which one or more of the non-rotating stator members are attached.

[0025] As will be discussed further herein, a slurry of wood pulp containing wood fibers passes through the refining spaces 60, 62. When the jackscrew rotates in a first direction, it causes the movable support frame 68 and the fourth refining element 50 to move inward toward the third refining element 40. The fourth refining element 50 then applies an axial force to the pulp slurry passing through the second refining space 62, which applies an axial force to the third refining element 40, causing the third refining element 40, support 70, and second refining element 30 to move inward toward the first refining element 20. When the jackscrew rotates in a second direction opposite the first direction, it causes the movable support frame 68 and the fourth refining element 50 to move outward and away from the third refining element 40. This reduces the axial force applied by the fourth refining member 50 to the pulp slurry passing through the second refining space 62, which in turn reduces the axial force applied by the pulp slurry to the third refining member 40. The axial force applied by the first and second refining spaces 60, 62 is then sufficient to cause the second refining member 30, the support 70, and the third refining member 40 to move toward the fourth refining member 50. This occurs until the axial forces applied against the second and third refining members 30 and 40 by the wood slurry passing through the first and second refining spaces 60, 62 are approximately equal.

[0026] In some embodiments (not shown), the disc refiner 10 can further include an additional motor and a second rotatable shaft, and the first and / or fourth refining members 20, 50 can be coupled to the second rotatable shaft, allowing the first and / or fourth refining members 20, 50 to be counter-rotatable relative to the second and / or third refining members 30, 40, respectively. In other embodiments (not shown), the disc refiner 10 can include only one pair of refining elements, with one refining element being a non-rotating stator element and the other being a rotating rotor element. In further embodiments (not shown), the disc refiner can include three or more pairs of refining elements. In yet further embodiments (not shown), the disc refiner 10 can include a conical refiner with one or more pairs of refining elements.

[0027] 2 and 3 are plan views of the refining surfaces 24, 34 of the first refining body 22 and the second refining body 32, respectively, for use in a pulp refiner according to one embodiment of the present disclosure. Although not discussed in detail herein, the structure of the refining surfaces 44, 54 of the third and fourth refining bodies 42, 52, respectively (see FIG. 1) can be substantially similar to the refining surfaces 24, 34 of the first and second refining bodies 22, 32, respectively.

[0028] 1 and 2, first refining body 22 can include multiple sections, e.g., sections 22A-22C, bolted or otherwise attached together to form disk-shaped refining body 22 including a radially outer edge 27. Refining surface 24 includes a plurality of elongated refiner bars 26, separated from one another by refiner grooves 28. Although not shown in FIG. 2, it is understood that other sections (not labeled) of first refining body 22 will similarly include refiner bars 26 and refiner grooves 28. Refiner bars 26 extend radially outward from radially inner location 23 toward radially outer edge 27 of first refining body 22. Refiner bars 26 can be angled at various angles as shown in Figure 2, and each section 22A-22C can include one or more segments (not separately labeled) of refiner bars 26 that are angled in different directions. The refiner bars 26 and refiner flutes 28 in each section 22A-22C in Figure 2 can be otherwise similar in structure.

[0029] As shown in FIG. 3, second refining body 32 can similarly include multiple sections, e.g., sections 32A-32C, bolted or otherwise attached together to form disk-shaped refining body 32 including radially outer edge 37. Refining surface 34 includes multiple elongated refiner bars 36 separated from one another by refiner grooves 38. Although not shown in FIG. 3, other sections (not labeled) of second refining body 32 can similarly include multiple sections, e.g., sections 32A-32C, bolted or otherwise attached together to form disk-shaped refining body 32 including radially outer edge 37. Refining surface 34 includes multiple elongated refiner bars 36 separated from one another by refiner grooves 38. It is understood that each section 32A-32C includes refiner bars 36 and refiner grooves 38. The refiner bars 36 extend radially outward from a radially inner location 33 toward a radially outer edge 37 of the second refining body portion 32. The refiner bars 36 can be angled at various angles as shown in FIG. 3, and each section 32A-32C can include two or more segments of refiner bars 36 (not separately labeled) that are angled in different directions. The refiner bars 36 and refiner grooves 38 in each section 32A-32C in FIG. 3 can also be otherwise similar in structure.

[0030] The path of a wood pulp slurry containing wood fibers through the refiner 10 is illustrated via arrow B in FIG. 1. Referring to FIGS. 1-3, the pulp slurry enters the disc refiner 10 through the inlet section 16 and passes through a central aperture 21 in the first refining member 20 into the refiner inner cavity 64. The refiner inner cavity 64 may be defined in part by a fixed support frame 66 and a movable support frame 68. The refining surfaces 24, 34 may include one or more additional rows of refiner bars (not labeled), such as those positioned near the center of the refining body sections 22, 32 (e.g., near the central aperture 21). These additional refiner bars are wider and spaced farther apart than the other refiner bars 26, allowing them to break down large fiber bundles before they enter the refining space 60. The wood fibers travel radially outward between the refining members 20, 30, 40, and 50. A first refining space 60 defined between the first refining member 20 and the second refining member 30 and a second refining space 62 defined between the third refining member 40 and the fourth refining member 50 define separate paths along which the wood fibers can travel from the inlet section 16 to the outlet section 18. It is contemplated that the wood fibers pass through only one of the first and second refining spaces 60, 62 at a time. The refiner flutes 28, 38 may be considered to be part of the refining space 60 defined between the first refining member 20 and the second refining member 30. It is contemplated that the majority of the wood fiber flow through the refining space 60 passes through the refiner flutes 28, 38. Similarly, the refiner grooves (not shown) of the third and fourth refining members 40, 50 can be considered to be part of the refining space 62 defined between the third refining member 40 and the fourth refining member 50.It is contemplated that the majority of the flow of wood fibers through the refining space 62 passes through the refiner channels (not labeled) of the third and fourth refining members 40, 50. After processing, the wood fibers exit the refiner 10 through the outlet section 18, at least partially under the influence of centrifugal force.

[0031] Figures 4A and 4B are detailed views of a portion of the refining surface 24 of the first refining body 22, and Figures 5A and 5B are detailed views of a corresponding portion of the refining surface 34 of the second refining body 32. Figures 6A and 6B are partial cross-sectional views of the refining bodies 22, 32 taken along lines 6A-6A and 6B-6B, respectively, illustrating two embodiments of refiner bars 26, 36 as shown in Figures 4A, 4B, 5A, and 5B. Figure 7 is a partial cross-sectional view taken along line 7-7 in Figures 4A, 4B, 5A, and 5B.

[0032] In the embodiments shown in Figures 4A, 5A, 6A, and 7, each refiner bar 26, 36 can include a first refiner bar 26A, 36A and a second refiner bar 26B, 36B. The refiner bars 26A, 36B may be separated from one another by first refiner grooves 28A, 38A, and the refiner bars 26B, 36B may be separated from one another by second refiner grooves 28B, 38B. The first and second refiner grooves 28A, 38A, 28B, 38B may have a width W of about 2.0 mm to about 6.0 mm. GThis range includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, and 6.0 mm. As shown in Figures 6A and 7, the first refiner bar 26A, 36A includes a first maximum height H1 extending upward from the floor F1 of the adjacent first refiner groove 28A, 38A, and the second refiner bar 26B, 36B includes a second maximum height H2 extending upward from the floor F2 of the adjacent second refiner groove 28B, 38B, where the second maximum height H2 is less than the first maximum height H1. The minimum height difference between H1 and H2 is shown as D1 in Figure 6A. In some examples, the radially outer portion RO1 of the first refiner bar 26A, 36A can include a step down from a first maximum height H1 to a second maximum height H2.

[0033] In some examples, the second maximum height H2 is at least as large as the first maximum height H1. Also 0 In another example, the second maximum height H2 can be at least 0.7 mm (±0.05 mm) less than the first maximum height H1. In a further example, the first maximum height H1 of the first refiner bar 26A, 36A, as measured from the floor F1 of the adjacent first refiner groove 28A, 38A, can be at least 0.35 mm (±0.05 mm) less than the first maximum height H1. 、4 .0mm ~1 The second maximum height H2 of the second refiner bar 26B, 36B can be 0.0 mm (±0.5 mm). This range includes all values ​​and subranges therebetween, including, for example, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm. In a particular example, the second maximum height H2 of the second refiner bar 26B, 36B, as measured from the floor F2 of the adjacent second refiner groove 28B, 38B, can be 0.0 mm (±0.5 mm). This range includes all values ​​and subranges therebetween, including, for example, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm. In a particular example, the second maximum height H2 of the second refiner bar 26B, 36B can be 0.0 mm (±0.5 mm) or less than the first maximum height H1 as measured from the floor F2 of the adjacent second refiner groove 28B, 38B. Also 0 .35mm ~1The range can be as small as 0.5 mm (±0.05 mm) or less. This range includes all values ​​and subranges therebetween, including, for example, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm. In another specific example, the second maximum height H2 of the second refiner bar 26B, 36B is less than the first maximum height H1 as measured from the floor F2 of the adjacent second refiner groove 28B, 38B. Also 0 .7mm ~1 The range can be as small as 0.5 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm. In yet a further example where the radially outer portion RO1 of the first refiner bar 26A, 36A includes a step down from a first maximum height H1 to a second maximum height H2, the second maximum height H2 can be at least 1 / 2 mm greater than the first maximum height H1. Also 1 In some cases, the second maximum height H2 may be at least 0.5 mm (±0.05 mm) smaller than the first maximum height H1. Also 2 In other cases, the second maximum height H2 may be less than the first maximum height H1 by at least 0.0 mm (±0.05 mm). Also 3 It is possible to achieve a tolerance as small as 0.0mm (±0.05mm).

[0034] Each of the first refiner bars 26A, 36A extends from a radially inward position P1 on the refining surfaces 24, 34 to a first radially outward position P2 on the refining surfaces 24, 34. Each of the second refiner bars 26B, 36B extends to a second radially outward position P3 on the refining surfaces 24, 34. The second radially outward position P3 can be closer to the outermost part (e.g., the radially outer edge 27, 37) of the refining body 22, 32 than the first radially outward position P2. In some examples, the radially inward position P1 can include a position at or near the radially inner location 23, 33. The second refiner bar 26B, 36B can include a longitudinal length L1 of about 0.6 cm to about 10 cm, preferably about 2 cm to about 10 cm. The first refiner bar 26A, 36A and the second refiner bar 26B, 36B can include a width W extending between the side edges of each refiner bar 26A, 36A, 26B, 36B of about 2.0 mm to about 8.0 mm. 26 This range includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, and 8.0 mm.

[0035] In some embodiments, the second refiner bar 26B, 36B can be integral with the first refiner bar 26A, 36A, as shown in Figures 4A, 5A, and 6A, such that the second refiner bar 26B, 36B extends from a first radially outward position P2 to a second radially outward position P3. In certain embodiments, the second refiner bar 26B, 36B can slope continuously downward from the first radially outward position P2 to the second radially outward position P3. As shown in Figure 6A, the height of the second refiner bar 26B, 36B can range from a second maximum height H2 to a second minimum height H 2’The height of the second refiner bar 26B, 36B may decrease continuously along substantially the entire longitudinal length L1 to a second maximum height H2. In another particular embodiment, the second refiner bar 26B, 36B may extend substantially horizontally from a first radially outward position P2 to a second radially outward position P3, as shown by the dotted line in FIG. 6A, such that the second refiner bar 26B, 36B has a second maximum height H2 along substantially the entire longitudinal length L1 of the second refiner bar 26B, 36B. In other embodiments (not shown), the first refiner bar 26A, 36A may be radially separated from the second refiner bar 26B, 36B by a predetermined space.

[0036] 4A, 5A, and 7, the refining surfaces 24, 34 can include dams 29, 39 provided within at least a portion of the first refiner flutes 28A, 38A. The dams 29, 39 can include a height that is substantially the same as or less than the height of the adjacent first refiner bars 26A, 36A. The dams 29, 39 serve to divert wood fibers from the first refiner flutes 28A, 38A for engagement by the first and second refiner bars 26A, 36A, 26B, 36B.

[0037] 1, 4A, 5A, and 6A, when a wood pulp slurry containing wood fibers is fed into the frame 66 (e.g., inlet section 16) of refiner 10, first refiner bars 26A, 36A are adapted to refine the wood fibers in the pulp slurry, while second refiner bars 26B, 36B are adapted to break up or separate fiber bundles. Refining can be used to break up and reduce small fiber agglomerates, induce external or internal fibrillation to achieve fiber bonding, and / or cut a significant number of long wood fibers in the wood pulp slurry so that their length is reduced. However, the refining process also causes some of the wood fibers to reform into small, dense fiber bundles ("flakes"), especially during the refining of long fibers such as softwoods. Fiber bundles can negatively impact downstream components such as the tensile strength, formation, and / or formation of the finished paper product, leading to a series of pulp seed formations clogging downstream components and / or disrupting the paper product production. This can inhibit fluid / water drainage from the fibers between the flakes. Therefore, flakes should be broken up after refining in a process called deflaking. As used herein, the term "deflaking" is used to describe the process of breaking up the fiber bundles formed during refining. When refining involves a conventional pulp refiner, deflaking typically occurs in one or more subsequent refiners, which often operate at low power and are referred to as "tickler" refiners or deflaker. The use of separate refiners or deflakers increases the cost and complexity of the system. Additionally, tickler refiners and associated lines and tanks, as well as downstream machine chests, can accumulate residual amounts of fiber from previous runs, allowing for the continued formation of fiber bundles. Processing in tickler refiners can degrade fiber properties when dissimilar pulp slurries are refined together. The refining members 20, 30, 40, 50 of the present disclosure are believed to solve these problems by incorporating refiner bars 26A, 26B, 36A, 36B of different heights so that refining and deflaking can be performed within a single refiner 10.

[0038] The first maximum height H1 of the first refiner bars 26A, 36A, which is greater than the second maximum height H2, means that the wood fibers are subjected to high shear and compressive forces as they pass through a portion of the refining space 60 that is at least partially defined by the first refiner grooves 28A, 38A and engaged by the cutting side edges 126A, 136A of the first refiner bars 26A, 36A on the opposing first and second refining surfaces 24, 34 (see also Figures 8 and 9). Thus, the portion of the refining space 60 that is at least partially defined by the first refiner grooves 28A, 38A and extends from a radially inward position P1 on the refining surfaces 24, 34 to a first radially outward position P2 on the refining surfaces 24, 34 can at least partially define a refining zone. In some examples, the radially inner locations 23, 33 of the respective refining bodies 22, 32 can define the beginning of a refining zone. As the refined fibers pass into the portion of the refining space 60 at least partially defined by the second refiner grooves 28B, 38B (e.g., from approximately the first radially outward position P2 to approximately the second radially outward position P3 in FIG. 6A ), the second refiner bars 26B, 36B include a second maximum height H2, and the intensity of the force applied to the fibers decreases in response to the reduced height (see also FIGS. 8 and 9 ). Thus, the portion of the refining space 60 at least partially defined by the second refiner grooves 28B, 38B and extending from the first radially outward position P2 to the second radially outward position P3 above the refining surfaces 24, 34 can at least partially define a deflaking zone. The reduction in force applied to the fibers in the deflaking zone is believed to break up the fiber bundles formed during refining without further refining the fibers or only minimally refining the fibers.In the embodiment shown in Figure 6A, the second refiner bars 26B, 36B form an annular ring that defines a deflaking zone around the radially outer portions (not separately labeled) of the first and second refining bodies 22, 32. Minimum height H 2’ teeth , to stop refining the fibers and to begin deflaking, the first refiner bars 26A, 36A must be lowered to at least the first maximum height H1. Also 0 It is believed that the refining zone should be less than 0.35 mm (±0.05 mm). The refining zone may comprise 60% or more of the total area defined by both the refining zone and the deflaking zone on each refining surface 24, 34.

[0039] In the embodiment shown in Figures 4B, 5B, and 6B, each refiner bar 26', 36' can include a first refiner bar 26A', 36A', a second refiner bar 26B', 36B', a third refiner bar 26C, 36C, and a fourth refiner bar 26D, 36D. The first refiner bar 26A', 36A' and the second refiner bar 26B', 36' can be substantially similar to the first refiner bar 26A, 36A and the second refiner bar 26B, 36B as shown in Figures 4A, 5A, 6A, and 7 and as described herein, except that the first and second refiner bars 26A', 36A', 26B', 36B' can extend radially outward a shorter distance. The first refiner bars 26A', 36A' may be separated from one another by first refiner grooves 28A', 38A', and the second refiner bars 26B', 36B' may be separated from one another by second refiner grooves 28B', 38B'. The first and second refiner grooves 28A', 38A', 28B', 38B' may have a width W of about 2.0 mm to about 6.0 mm. GThis range includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, and 6.0 mm. The third refiner bars 26C, 36C can be separated from one another by third refiner grooves 28C, 38C, and the fourth refiner bars 26D, 36D can be separated from one another by fourth refiner grooves 28D, 38D. As shown in FIG. 6B, the third refiner bar 26C, 36C includes a third maximum height H3 extending upward from the floor F3 of the adjacent third refiner groove 28C, 38C, and the fourth refiner bar 26D, 36D includes a fourth maximum height H4 extending upward from the floor F4 of the adjacent fourth refiner groove 28D, 38D, the fourth maximum height H4 being less than the third maximum height H3. 1’ and the fourth maximum height H4 can be substantially equal to the second maximum height H2. The minimum height difference between H3 and H4 is shown as D2 in FIG. 6B. In some examples, the radially outer portion RO2 of the third refiner bar 26C, 36C can include a step-down from the third maximum height H3 to the fourth maximum height H4. The third and fourth refiner grooves 28C, 38C, 28D, 38D can have a width W of about 2.0 mm to about 6.0 mm. G This range includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, and 6.0 mm.

[0040] In some examples, the fourth maximum height H4 can be at least 0.35 mm (±0.05 mm) less than the third maximum height H3. In other examples, the fourth maximum height H4 can be at least 0.7 mm (±0.05 mm) less than the third maximum height H3. In further examples, the third maximum height H3 of the third refiner bar 26C, 36C, as measured from the floor F3 of the adjacent third refiner groove 28C, 38C, can be at least 0.7 mm (±0.05 mm) less than the third maximum height H3.、4 .0mm ~1 The fourth maximum height H4 of the fourth refiner bar 26D, 36D can be greater than or equal to 0.0 mm (±0.5 mm). This range includes all values ​​and subranges therebetween, including, for example, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm. In a particular example, the fourth maximum height H4 of the fourth refiner bar 26D, 36D, as measured from the floor F4 of the adjacent fourth refiner groove 28D, 38D, can be greater than the third maximum height H3. Also 0 .35mm ~1 The range can be as small as 0.5 mm (±0.05 mm). This range includes, for example, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm. , including all values ​​and subranges therebetween. In another particular example, the fourth maximum height H4 of the fourth refiner bar 26D, 36D is greater than the third maximum height H3 as measured from the floor F4 of the adjacent fourth refiner groove 28D, 38D. Also 0 .7mm ~1 The range can be as small as 0.5 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm. In yet a further example, in which the radially outer portion RO2 of the third refiner bar 26C, 36C includes a step-down from the third maximum height H3 to the fourth maximum height H4, the fourth maximum height H4 is at least 0.5 mm (±0.05 mm) smaller than the third maximum height H3. Also 1 In some cases, the fourth maximum height H4 may be at least 0.5 mm (±0.05 mm) smaller than the third maximum height H3. Also 2In other cases, the fourth maximum height H4 may be less than the third maximum height H3 by at least 0.0 mm (±0.05 mm). Also 3 It is possible to achieve a tolerance as small as 0.0mm (±0.05mm).

[0041] Each of the first refiner bars 26A′, 36A′ is positioned at a radially inward position P on the refining surface 24, 34. 1’ to a first radially outward position P on the refining surfaces 24, 34 2’ Each of the second refiner bars 26B', 36B' extends to a second radially outward position P on the refining surfaces 24, 34. 3’ Each of the third refiner bars 26C, 36C extends to a third radially outward position P4 on the refining surfaces 24, 34. Each of the fourth refiner bars 26D, 36D extends to a fourth radially outward position P5 on the refining surfaces 24, 34. The fourth radially outward position P5 is located between the first, second, and third radially outward positions P 2’ , P 3’ and P4 may be closer to the outermost parts of the refining body portions 22, 32, e.g., the radially outer edges 27, 37. The fourth refiner bar 26D, 36D may have a longitudinal length L2 of about 0.6 cm to about 10 cm, preferably about 2 cm to about 10 cm. The third refiner bar 26C, 36C and the fourth refiner bar 26D, 36D may have a width (not separately labeled) extending between the side edges of each refiner bar 26C, 36C, 26D, 36D of about 2.0 mm to about 8.0 mm. This range includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, and 8.0 mm.

[0042] In some embodiments, the second refiner bars 26B', 36B' can be integral with the first refiner bars 26A', 36A', as shown in Figures 4B, 5B, and 6B, and the second refiner bars 26B', 36B' are positioned at the first radially outward position P 2’ to a second radially outward position P 3’ In some embodiments, as shown in Figures 4B, 5B, and 6B, the third refiner bar 26C, 36C can be integral with the second refiner bar 26B', 36B', such that the third refiner bar 26C, 36C extends to the second radially outward position P 3’ to a third radially outward position P 4’ The fourth refiner bar 26D, 36D can be integral with the third refiner bar 26C, 36C such that the fourth refiner bar 26D, 36D extends from the third radially outward position P4 to the fourth radially outward position P5. In certain embodiments, the second refiner bar 26B', 36B' extends from the first radially outward position P 2’ to a second radially outward position P 3’ As shown in FIG. 6B, second refiner bar 26B', 36B' can have a longitudinal length L1 of about 0.6 cm to about 10 cm, preferably about 2 cm to about 10 cm. The height of B', 36B' is the difference between the second maximum height H2 and the second minimum height H 2’ In another particular embodiment, the second refiner bars 26B', 36B' may be spaced apart from the first radially outward position P along substantially the entire longitudinal length L1. 2’ to a second radially outward position P 3’The second refiner bar 26B', 36B' may extend substantially horizontally to a fourth maximum height H2 along substantially the entire longitudinal length L1 of the second refiner bar 26B', 36B'. In certain embodiments, the fourth refiner bar 26D, 36D may slope continuously downward from a third radially outward position P4 to a fourth radially outward position P5. As shown in FIG. 6B , the height of the fourth refiner bar 26D, 36D may slope continuously downward from a fourth maximum height H4 to a fourth minimum height H 4’ The height of the fourth refiner bar 26D, 36D may decrease continuously along substantially the entire longitudinal length L2 to a fourth maximum height H4. In another particular embodiment, the fourth refiner bar 26D, 36D may extend substantially horizontally from a third radially outward position P4 to a fourth radially outward position P5, as shown by the dotted line in FIG. 6B, such that the fourth refiner bar 26D, 36D has a fourth maximum height H4 along substantially the entire longitudinal length L2 of the fourth refiner bar 26D, 36D. In other embodiments (not shown), the third refiner bar 26C, 36C may be radially separated from the fourth refiner bar 26D, 36D by a fixed space.

[0043] Referring to Figures 4B, 5B, and 7, the refining surfaces 24, 34 may include dams 29, 39 provided within at least a portion of the first and / or third refiner grooves 28A', 38A', 28C, 38C, as described herein.

[0044] As described with respect to the first and second refiner bars 26A, 36A, 26B, 36B in Figures 4A, 5A, and 6A, the first refiner bar 26A', 36A' in Figures 4B, 5B, and 6B is adapted to refine wood fibers, and the second refiner bar 26B', 36B' in Figures 4B, 5B, and 6B is adapted to break down fiber bundles. The third refiner bar 26C, 36C is adapted to refine wood fibers (similar to the first refiner bar 26A', 36A'), while the fourth refiner bar 26D, 36D is adapted to break down fiber bundles (similar to the second refiner bar 26B', 36B') as described herein.

[0045] 1, 4B, 5B, and 6B, the first refiner grooves 28A′, 38A′ and the third refiner grooves 28C, 38C are at least partially defined by a radially inward position P on the refining surfaces 24, 34. 1’ to a first radially outward position P 2’ to, and to a second radially outward position P 3’ The portions of the refining space 60 extending from the first radially outward location P4 on the refining surfaces 24, 34 may at least partially define first and second refining zones, respectively, as described herein. 2’ to a second radially outward position P 3’The portions of refining space 60 extending from third radially outward location P4 to fourth radially outward location P5 may at least partially define first and second deflaking zones, respectively, as described herein. The second maximum height H2 of second refiner bars 26B', 36B' is at least 1 / 3 the first maximum height H1 of first refiner bars 26A', 36A' to stop refining the fibers and to begin deflaking. Also 0 It should be smaller than 0.35mm (±0.05mm). Similarly, the fourth maximum height H4 of the fourth refiner bars 26D, 36D must be at least as large as the third maximum height H3 of the third refiner bars 26C, 36C to stop refining the fibers and to begin deflaking. Also 0 It is believed that the area between the first and second refining zones should be less than 0.35 mm (±0.05 mm). The first and second refining zones may comprise 60% or more of the total area defined by both the first and second refining zones and the deflaking zone on the respective refining surfaces 24, 34.

[0046] 8 and 9 are partial cross-sectional views of the first and second refining bodies 22, 32 / 132 of the first and second refining members 20, 30 / 130 according to the present disclosure. The first refining member 20 is spaced apart from and positioned adjacent to and directly opposite the second refining member 30 (see FIG. 1). In the embodiment shown in FIG. 8, a refining body according to the present invention, e.g., the first refining body 22, is paired with a conventional refining body 132. First refining body 22 includes first refiner bar 26A, first refiner groove 28A, second refiner bar 26B, and second refiner groove 28B, which can correspond to first and second refiner bars 26A, 26B and first and second refiner grooves 28A, 28B as described herein with respect to Figures 4A, 4B, 6A, 6B, and 7. It is understood that the features described in Figure 8 with respect to first and second refiner bars 26A, 26B and first and second refiner grooves 28A, 28B apply equally to third and fourth refiner bars 26C, 26D and third and fourth refiner grooves 28C, 28D, respectively, as described herein (see Figures 4B, 5B, and 6B). Conventional refining body 132 includes conventional refiner bars 136 and refiner grooves 138, with the conventional refiner bars 136 having a uniform height along substantially the entire longitudinal length of refiner bar 136. In other embodiments (not shown), a non-rotating stator member, e.g., first refining member 20, can include conventional refiner bars having a uniform height along substantially the entire length, and a rotating rotor member, e.g., second refining member 30, can include refiner bars 26A, 26B and refiner grooves 28A, 28B (see FIG. 1) according to the present disclosure.

[0047] The first gap G1 is located between the outer surface S of the first refiner bar 26A in FIG. 26A and the outer surface S of the conventional refiner bar 136 136 In the example where second refiner bar 26B is continuously sloped downward, second gap G2 is defined between outer surface S of second refiner bar 26B. 26B and the outer surface S of the conventional refiner bar 136, where G2 is greater than G1. In an example where the second refiner bar 26B extends substantially horizontally (shown by the dotted line in FIG. 8), a third gap G3 may be defined between the outer surface S of the second refiner bar 26B and the outer surface S of the conventional refiner bar 136. 26B’ and the outer surface S of the conventional refiner bar 136 136 8, in an embodiment in which one of the second refiner bars (e.g., second refiner bar 26B) is sloped, the outer surface S of second refiner bar 26B may be defined as 26B and the outer surface S of the conventional refiner bar 136 136 The distance between may increase continuously along at least a portion of the longitudinal length of the second refiner bar 26B (not labeled; see Figures 6A and 6B) from a minimum distance corresponding to the third gap G3 to a maximum distance corresponding to the second gap G2.

[0048] In the embodiment shown in FIG. 9, one refining body according to the invention, e.g. For example, first refining body 22 is paired with another refining body according to the present invention, e.g., second refining body 32. First refining body 22 includes first refiner bar 26A, first refiner groove 28A, second refiner bar 26B, and second refiner groove 28B, which can correspond to first and second refiner bars 26A, 26B and first and second refiner grooves 28A, 28B as described herein with respect to Figures 4A, 4B, 6A, 6B, and 7. The second refining body portion 32 includes a first refiner bar 36A, a first refiner groove portion 38A, a second refiner bar 36B, and a second refiner groove portion 38B, which may correspond to the first and second refiner bars 36A, 36B and the first and second refiner groove portions 38A, 38B as described herein with respect to Figures 5A, 5B, 6A, 6B, and 7. It is understood that the features described in Figure 9 with respect to the first and second refiner bars 26A, 26B, 36A, 36B and the first and second refiner grooves 28A, 28B, 38A, 38B apply equally to the third and fourth refiner bars 26C, 26D and the third and fourth refiner grooves 28C, 28D, respectively, as described herein (see Figures 4B, 5B, and 6B).

[0049] The first gap G1 is formed by the gap between the outer surface S of the first refiner bar 26A of the first refining body 22. 26A and the outer surface S of the first refiner bar 36A of the second refining body portion 32. 36A In the example where the second refiner bar 26B of the first refining body 22 and the second refiner bar 36B of the second refining body 32 are both continuously sloped downward, the gap G4 is defined between the outer surface S of the second refiner bar 26B. 26B and the outer surface S of the second refiner bar 36B of the second refining body portion 32. 36Band G4 is greater than G1. In an example where one of the second refiner bars (e.g., second refiner bar 26B of first refining body 22) is continuously inclined downward and the other of the second refiner bars (e.g., second refiner bar 36B of second refining body 32) extends substantially horizontally (shown in FIG. 9 by the dotted line), gap G5 is defined between the outer surface S of second refiner bar 26B and the outer surface S of second refiner bar 26B. 26B and the outer surface S of the second refiner bar 36B 36B’ In an example where the second refiner bar 26B of the first refining body 22 and the second refiner bar 36B of the second refining body 32 both extend substantially horizontally (shown in FIG. 9 by the dotted lines), the gap G6 may be defined between the outer surface S of the second refiner bar 26B and the outer surface S of the second refiner bar 26B. 26B’ and the outer surface S of the second refiner bar 36B 36B’ and G6 is greater than G1. In some specific examples, G4 is greater than G5, and G5 is greater than G6.

[0050] In embodiments in which one or both of the second refiner bars 26B, 36B are angled, as shown in FIG. 9, the outer surface S of the second refiner bars 26B, 36B 26B , S 26B’ , S 36B , S 36B’ The distance between the second refiner bars 26B, 36B can increase continuously along at least a portion of the longitudinal length (not labeled; see Figures 6A and 6B) of one or both of the respective second refiner bars 26B, 36B. For example, when one refining body, e.g., the first refining body 22, includes inclined second refiner bars 26B, the outer surface S of the second refiner bars 26B, 36B can be increased. 26B , S 36B’The distance between the second refiner bars 26B, 36B can increase from a minimum distance corresponding to the gap G6 to a maximum distance corresponding to the third gap G5. When both refining body portions 22, 32 include inclined second refiner bars 26B, 36B, the outer surfaces S of the second refiner bars 26B, 36B 26B , S 36B The distance between them is the minimum distance corresponding to the gap G6 to the second gap G7. It is possible to increase the maximum distance corresponding to group G4.

[0051] In all of the embodiments shown in Figures 8 and 9, when a rotatable refining element (e.g., first refining element 20; see Figure 1) rotates relative to a stationary refining element (e.g., second refining element 30 / 130; see Figure 1), a pulp slurry containing wood fibers is supplied to the frame 66 (e.g., inlet portion 16) (see Figure 1) of the refiner 10 and enters the refining space 60 defined between the first refining body portion 22 and the second refining body portion 32 / 132. Referring to FIG. 8 , the first and second refining bodies 22, 132 are spaced apart to define a first gap G1 between the first refiner bar 26A of the first refining body 22 and the conventional refiner bar 136 of the second refining body 132 as wood fibers enter the portion of the refining space 60 defined at least in part by the first refiner groove 28A of the first refining body 22 and the refiner groove 138 of the second refining body 132, such that the refiner bars 26A and 136 interact with each other to refine the wood fibers, as described herein. The first gap G1 is defined to allow refining to occur. 、0 It should be smaller than 0.9mm (±0.05mm), preferably 、0 .2mm or et al.It is contemplated that the first gap G1 should be 0.9 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, and 0.9 mm. In some examples, the first gap G1 is 0 .1mm ~0 The range can be 0.5 mm (±0.05 mm), including all values ​​and subranges therebetween, including, for example, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, and 0.5 mm.

[0052] 8 , as wood fibers pass into the portion of the refining space 60 defined at least in part by the second refiner groove 28B of the first refining body 22 and the refiner groove 138 of the second refining body 132, the distance between the second refiner bar 26B of the first refining body 22 and the refiner bar 136 of the second refining body 132 is increased, such that refining stops and deflaking begins. In an embodiment in which the second refiner bar 26B is continuously tilted downward, the distance increases from the first gap G1 to the second gap G2. In an embodiment in which the second refiner bar 26B extends substantially horizontally, the distance increases from the first gap G1 to the third gap G3. To allow deflaking to occur, the distance between the second refiner bar 26B of the first refining body 22 and the refiner bar 136 of the second refining body 132, i.e., G2 or G3, is 、0 .9mm ~1It is contemplated that the thickness should be 0.5 mm (±0.05 mm), which range includes all values ​​and subranges therebetween, including, for example, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm.

[0053] Referring to FIG. 9 , the first and second refining bodies 22, 32 are spaced apart to define a first gap G1 between the first refiner bars 26A, 36A when wood fibers enter the portion of the refining space 60 defined at least in part by the first refiner grooves 28A, 38A of the first and second refining bodies 22, 32, respectively, so that the refiner bars 26A, 36A interact with each other to refine the wood fibers as described herein. As wood fibers pass into the portion of the refining space 60 defined at least in part by the second refiner grooves 28B, 38B of the first and second refining bodies 22, 32, respectively, the distance between the second refiner bar 26B of the first refining body 22 and the second refiner bar 36B of the second refining body 32 increases to one of gaps G4, G5, or G6, so that refining stops and deflaking begins. The first gap G1 should be less than 0.9 mm (±0.05 mm) for refining to occur, and preferably less than 0.2 mm. ~0 The first gap G1 should be 0.9 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, and 0.9 mm. In some examples, the first gap G1 is 、0 .1mm ~0The gaps G4, G5, and G6 can be 0.5 mm (±0.05 mm), which range includes all values ​​and subranges therebetween, including, for example, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, and 0.5 mm. Also, to allow deflaking to occur, the gaps G4, G5, and G6 can be 、0 .9mm ~1 It is contemplated that the range should be within 0.5 mm (±0.05 mm). This range, for example, from about 0.9 mm to about 1.5 mm, includes all values ​​and subranges therebetween, including 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm.

[0054] 1, 6A, 6B, 8, and 9, gaps G1 and G2, G3, G4, G5, G6 defined between refining body portions 22, 32 / 132 can be adjusted by applying axial pressure to at least one of first or second refining members 20, 30, for example, via a second motor 76 coupled to movable support frame 68 via a jackscrew (not shown). For a single-disc refiner, second refining member 30 can be directly coupled to movable support frame 68 such that second refining member 30 moves with movable support frame 68 when movable support frame 68 is moved via second motor 76 and jackscrew. For the double-disc refiner 10, when the second refining member 30 is moved as described above, i.e., when the jackscrew rotates in a first direction, it causes the movable support frame 68 and the fourth refining member 50 to move inward toward the third refining member 40. The fourth refining member 50 then applies an axial force to the wood slurry passing through the second refining space 62, which applies an axial force to the third refining member 40, causing the third refining member 40, support 70, and second refining member 30 to move inward toward the first refining member 20.

[0055] The gap G1 defined between the refiner bars 26A, 36A, 136 can be maintained at a substantially constant gap value by adjusting the positioning of the second refining member 30 relative to the first refining member 20 via the second motor 76 (controlled manually or via a controller / processor coupled to the second motor 76) and jackscrew, such that the amount of power required to be input / generated by the first motor 74 (controlled manually or via a controller / processor coupled to the first motor 74) operating at a predetermined rotational speed to process a constant amount of pulp flowing through the refining space 60 is maintained at a predetermined input power level, which can be controlled by an operator or a controller controlling the first motor 74. For example, if the pulp is 0.572 m 3 When moving through the refining space 60 of a 20-inch diameter Andritz® Twinflo IIIB low consistency refiner at a flow rate of 151 gallons per minute and the first motor 74 is running at a constant rotational speed of 800 RPM, the second motor 76 is controlled to move the second refining element 30 relative to the first refining element 20 until the power input by the first motor 74 is equal to 114 kilowatts. When the power input by the first motor 74 is equal to 114 kilowatts, the gap size between the first refining element 20 and the second refining element 30 is estimated to be 0.57 mm.

[0056] 1, 6A, 6B, 8, and 9, it is contemplated that the gaps G2, G3, G4, G5, G6 required to achieve deflaking can vary depending on the load or flow rate (i.e., liters per minute of pulp slurry flowing through the refining space 60) to which the refining body 22, 32 / 132 is exposed. For example, when the refining body 22, 32 / 132 is lightly loaded, refining of the wood fibers can stop and deflaking can begin almost immediately upon passage of the fibers into the portion of the refining space 60 defined at least in part by the second refiner grooves 28B / 28B', 38B / 38B', e.g., upon movement of the wood fibers through the first radially outward position P2 / P2' and / or the third radially outward position P4, as shown in FIGS. 6A and 6B. When the refining body 22, 32 / 132 is heavily loaded, some refining of the wood fibers can continue along at least a portion of the refining space 60 that is at least partially defined by the second refiner grooves 28B / 28B', 38B / 38B'.

[0057] In situations where the refining body 22, 32 / 132 is heavily loaded, an embodiment in which one or both of the second refiner bars 26B / 26B' of the first refining body 22 and the second refiner bars 36B / 36B' of the second refining body 32 are continuously sloped downward can be particularly advantageous for ensuring that a sufficient distance between the refiner bars 26B / 26B' and the refiner bars 136 / 36B / 36B' is achieved along at least a portion of the refining space 60 defined at least in part by the second refiner grooves 28B / 28B', 38B / 38B, allowing refining to stop and deflaking to occur. Additionally, the refining surfaces 24, 34 of the refining body 22, 32 can wear and deteriorate over time. In particular, the first and third refiner bars 26A / 26A', 26C, 36A / 36A', 36C, which perform the majority of the high-intensity, high-energy refining, may wear faster than the second and fourth refiner bars 26B / 26B', 26D, 36B / 36B', 36D, which perform deflaking (which is generally lower intensity and energy than refining). The position of the refining body 22, 32 / 132 is adjusted as described herein to increase the first gap G1 between the first and third refiner bars 26A / 26A', 26C, 36A / 36A', 36C and their outer surfaces S 26A , S 36A However, the gaps G2, G3, G4, G5, G6 between the second and fourth refiner bars 26B / 26B', 26D, 36B / 36B', 36D may not be adjustable. Therefore, embodiments in which one or both of the second refiner bars 26B / 26B', 36B / 36B' and / or one or both of the fourth refiner bars 36B / 36B', 36D are angled may be used to reduce the amount of refining. It is believed that the transition between the densifying zone and the deflaking zone allows the second and fourth refiner bars 26B / 26B', 26D, 36B / 36B', 36D to shift radially outward along their longitudinal lengths (not labeled; see Figures 6A and 6B) as the first and third refiner bars 26A / 26A', 26C, 36A / 36A', 36C wear down.

[0058] 10 and 11 are plan views of portions of the refining surfaces of the first refining body 22′ and the second refining body 32, respectively, according to another embodiment of the present disclosure. Referring to FIGS. 1, 10, and 11, the first and second refining bodies 22′, 32′ can each be part of a refining member (e.g., first and second refining members 20, 30) for use in a pulp refiner, such as the disc refiner 10 shown in FIG. 1, as described herein. Each of the refining members 20, 30, including the first and second refining bodies 22′, 32′, respectively, can be associated with a main support frame, which includes a fixed support frame 66 fixed to the first housing section 12 and a movable support frame 68. One refining member (e.g., first refining member 20 including first refining body 22′) can be secured to support frame 66 of refiner 10 and define a non-rotating stator member. Another refining member (e.g., second refining member 30 including second refining body 32′) can be secured to support 70, which defines a rotor that rotates with shaft 72 and is associated with the main support frame, such that rotation of the rotor effects movement of second refining member 30 relative to first refining member 20. Third and fourth refining members (not shown) can also be provided having third and fourth refining bodies similar to first and second refining bodies 22′, 32′.

[0059] As shown in FIG. 10 , first refining body 22′ includes multiple sections 22A′-22C′, which may be bolted or otherwise attached together to form a disk-shaped refining body 22′ that includes a radially outer edge 27. Each section 22A′-22C′ includes multiple elongated refiner bars 26′, which are separated from one another by refiner grooves 28′. Although not shown in FIG. 10 , it is understood that other sections (not labeled) of first refining body 22′ will similarly include refiner bars 26′ and refiner grooves 28′. Refiner bars 26′ extend radially outward from radially inner location 23′ toward a radially outer edge 27′ of first refining body 22′. Each section 22A'-22C' of the first refining body portion 22' can include one or more radially extending pie-shaped segments, including at least one first pie-shaped segment 22B-1 and at least one second pie-shaped segment 22B-2.

[0060] As shown in FIG. 11 , the second refining body 32′ includes a corresponding plurality of sections 32A′-32C′, which may be bolted or otherwise attached together to form a disk-shaped refining body 32′ including a radially outer edge 37′. Each section 32A′-32C′ includes a plurality of elongated refiner bars 36′, which are separated from one another by refiner grooves 38′. Although not shown in FIG. 11 , it is understood that other sections (not labeled) of the second refining body 32′ will similarly include refiner bars 36′ and refiner grooves 38′. The refiner bars 36′ are spaced radially inward from one another. The second refining body 32' extends radially outward from the first refining body 33' toward the radially outer edge 37' of the second refining body 32'. Each section 32A'-32C' of the second refining body 32' can include one or more radially extending pie-shaped segments, including at least one first pie-shaped segment 32B-1 and at least one second pie-shaped segment 32B-2. Although not discussed in detail herein, the third and fourth refining bodies 42, 52 of FIG. 1 can include a structure substantially similar to the first and second refining bodies 22', 32', respectively, as described herein.

[0061] At least one of the first and second refining body portions 22', 32' in Figures 10 and 11 includes one or more sections 22A'-22C', 32A'-32C' with at least one radially extending pie-shaped segment (e.g., 22B-1 and 32B-1) of refiner bar 26', 36' that includes one or more characteristics different from the refiner bar 26', 36' in the adjacent radially extending pie-shaped segment (e.g., 22B-2 and 32B-2). Figures 12A and 12B are partial cross-sectional views in which the first and second refining body portions 22', 32' in Figures 10 and 11 are spaced apart from each other and positioned adjacent to and directly across from each other (see Figure 1). In FIG. 12A, the first refiner bar 26-1 may be positioned on the refining surface 24-1 (also referred to herein as the first refining surface) of at least one first pie-shaped segment 22B-1 of the first refining body portion 22′, and the first refiner bar 26-1 may be spaced apart from the third refiner bar 36-1 and positioned adjacent to and directly opposite the third refiner bar 36-1, and the third refiner bar 36-1 may be positioned on the refining surface 34-1 (also referred to herein as the third refining surface) of at least one third pie-shaped segment 32B-1 of the second refining body portion 32′.In FIG. 12B, the second refiner bar 26-2 may be positioned on the refining surface 24-2 (also referred to herein as the second refining surface) of at least one second pie-shaped segment 22B-2 of the first refining body portion 22′, and the second refiner bar 26-2 may be spaced apart from the fourth refiner bar 36-2 and positioned adjacent to and directly opposite the fourth refiner bar 36-2, and the fourth refiner bar 36-2 may be positioned on the refining surface 34-2 (also referred to herein as the fourth refining surface) of at least one fourth pie-shaped segment 32B-2 of the second refining body portion 32′.

[0062] 10, 11, and 12A, the first refiner bars 26-1 are separated from one another by first refiner grooves 28-1, and the floor F of each adjacent first refiner groove 28-1 is 1’ A first maximum height H extending upward from 10 The third refiner bars 36-1 are separated from one another by third refiner grooves 38-1, and the floor F of each adjacent third refiner groove 38-1 may be 3’ a third maximum height H extending upward from 30 As shown in FIG. 12A, the first and third refiner bars 26-1, 36-1 can be substantially similar to one another and can include first and third maximum heights H 10 , H 30 can be substantially equal.

[0063] 10, 11, and 12B, the second refiner bars 26-2 are separated from one another by second refiner grooves 28-2, and the floors F of adjacent second refiner grooves 28-2 are 2’ A second maximum height H extending upward from 20 The fourth refiner bar 36-2 may include a fourth refiner groove 38-2. and the floor F of the adjacent fourth refiner groove section 38-2. 4’ A fourth maximum height H extending upward from 40 As shown in FIG. 12B, the second and fourth refiner bars 26-2, 36-2 can be substantially similar to one another and can include second and fourth maximum heights H 20 , H 40 may be substantially equal. All of the refiner bars 26-1, 26-2, 36-1, 36-2 in each pie-shaped segment 22B-1, 22B-2, 32B-1, 32B-2 may include the same height relative to one another.

[0064] the second maximum height H of the second refiner bar 26-2 20 is the first maximum height H of the first refiner bar 26-1 10 In some examples, the second maximum height H 20 is the floor F of the adjacent second refiner groove section 28-2 2’ The first maximum height H when measured from 10 In another example, the second maximum height H 20 is the floor F of the adjacent second refiner groove section 28-2 2’ The first maximum height H when measured from 10 In a further example, the first maximum height H of the first refiner bar 26-1 can be at least 0.7 mm (±0.05 mm) smaller than 10 is the floor F of each adjacent first refiner groove section 28-1 1’ When measured from 、4 .0mm ~1The second maximum height H of the second refiner bar 26-2 can be 0.0 mm (±0.5 mm), including all values ​​and subranges therebetween, for example, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm. In a particular example, the second maximum height H of the second refiner bar 26-2 can be 0.0 mm (±0.5 mm), including all values ​​and subranges therebetween, for example, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm. 20 is the floor F of each adjacent second refiner groove section 28-2 2’ The first maximum height H when measured from 10 twist Also 0 .35mm ~1 The second maximum height H of second refiner bar 26-2 can be as small as 0.5 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm. In another specific example, the second maximum height H of second refiner bar 26-2 is 0.5 mm (±0.05 mm). 20 is the floor F of each adjacent second refiner groove section 28-2 2’ The first maximum height H when measured from 10 twist Also 0 .7mm ~1The width can be as small as 0.5 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm. In a further example, the first refiner bar 26-1 and the second refiner bar 26-2 can include a width (not shown; see FIG. 7) extending between the side edges of each refiner bar 26-1, 26-2 of about 2.0 mm to about 8.0 mm. This range includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, and 8.0 mm. 40 (It is the second maximum height H 20 ) corresponds to the third maximum height H of the third refiner bar 36-1. 30 (It is the first maximum height H 10 It is possible for the .DELTA..times ...

[0065] 1, 10, 11, 12A, and 12B, as the second refining member 30 rotates relative to the first refining member 20, the refining surface 34-1 of the at least one third pie-shaped segment 32B-1 of the second refining body 32′ passes over the refining surface 24-1 of the at least one first pie-shaped segment 22B-1 of the first refining body 22′, The refining surface 34-2 of the at least one fourth pie-shaped segment 32B-2 of the second refining body 32' passes over the refining surface 24-2 of the at least one second pie-shaped segment 22B-2 of the first refining body 22'. When the wood pulp slurry is fed into the frame 66 (e.g., the inlet section 16) of the refiner 10 and passes through the refining space 60, the refining surface 34-1 of the at least one third pie-shaped segment 32B-1 of the second refining body 32' passes over the refining surface 24-1 of the at least one first pie-shaped segment 22B-1 of the first refining body 22', the third maximum height H 30 The third refiner bar 36-1 has a first maximum height H 10 The first and third refiner bars 26-1 and 36-1 are positioned opposite the first refiner bar 26-1 having a fourth maximum height H 1 , so that the first and third refiner bars 26-1 and 36-1 refine a significant number of wood fibers. When the refining surface 34-2 of the at least one fourth pie-shaped segment 32B-2 of the second refining body 32' passes over the refining surface 24-2 of the at least one second pie-shaped segment 22B-2 of the first refining body 22', the refining surface 34-2 of the at least one second pie-shaped segment 22B-2 of the first refining body 22' reaches a fourth maximum height H 1 . 40 The fourth refiner bar 36-2 has a second maximum height H 20The second and fourth refiner bars 26-2 and 36-2 are positioned opposite the second refiner bar 26-2 having the third pie-shaped segment 32B-1, and are configured to break down or separate the wood fiber bundles in the wood pulp slurry as described herein. Low-intensity refining can occur when the refining surface 34-1 of the at least one third pie-shaped segment 32B-1 of the second refining body 32' passes over the refining surface 24-2 of the at least one second pie-shaped segment 22B-2 of the first refining body 22' and when the refining surface 34-2 of the at least one fourth pie-shaped segment 32B-2 of the second refining body 32' passes over the refining surface 24-1 of the at least one first pie-shaped segment 22B-1 of the first refining body 22'.

[0066] 10 and 11, one or more of sections 22A'-22C', 32A'-32C' of each refining body 22', 32' may, in some examples, include three radially extending pie-shaped segments 22B-1, 22B-1, 22B-3 and 32B-1, 32B-2, 32B-3, respectively. In some particular examples, two segments (e.g., 22B-1, 22B-3 and 32B-1, 32B-3) may each have a first or second maximum height H 10 , H 20 and one segment (e.g., 22B-2 and 32B-2) may include refiner bars having one of the first or second maximum heights H 10 , H 20 and a second maximum height H 20 is the first maximum height H 10For example, segments 22B-1, 22B-3 can include first refiner bar 26-1, segments 32B-1, 32B-3 can include third refiner bar 36-1, segment 22B-2 can include second refiner bar 26-2, and segment 32B-2 can include fourth refiner bar 36-2. In other examples (not shown), one or more of sections 22A'-22C', 32A'-32C can each include only two segments of refiner bars, or four or more segments of refiner bars. In further examples (not shown), one or more of sections 22A'-22C', 32A'-32C' may not include separate segments, such that the entire section includes a single height of refiner bars. It is understood that a refining body according to the present disclosure (e.g., one of refining bodies 22', 32') can be paired with a refining body including conventional refiner bars (e.g., refiner bars that are all the same height).

[0067] For refining to occur, the gap between the opposing first and third refiner bars 26-1, 36-1 is 、0 It should be less than 0.9mm (±0.05mm), preferably is 0 .2mm ~0 The gap between the opposing second and fourth refiner bars 26-2, 36-2 should be 0.9 mm (±0.05 mm) to allow deflaking to occur. is 0 .9mm ~1It is contemplated that the thickness should be within 0.5 mm (±0.05 mm). Each of these ranges includes all values ​​and subranges therebetween, including, for example, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, and 0.9 mm for the range of about 0.2 mm to about 0.9 mm, and 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm for the range of about 0.9 mm to about 1.5 mm. In some examples, the gap between the opposing first and third refiner bars 26-1, 36-1 is 、0 .1mm ~0 The range can be 0.5 mm (±0.05 mm), including all values ​​and subranges therebetween, including, for example, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, and 0.5 mm.

[0068] 19A and 19B are partial cross-sectional views, similar to those of FIGS. 6A and 6B, of a first refining body 1022, 1022' having a respective first refining surface 1024, 1024' and a second refining body 1032, 1032' having a respective second refining surface 1034, 1034'. As described in detail herein, the first and second refining body 1022 / 1022', 1032 / 1032' can be part of a refining member, e.g., refining members 20, 30, respectively, in FIG. 1, for use in a pulp refiner such as the disc refiner 10 shown in FIG. 1. Each of the refining members 20, 30, including the first and second refining body portions 1022 / 1022′, 1032 / 1032′, can be associated with a main support frame, including a fixed support frame 66 fixed to the first housing section 12 and a movable support frame 68. One refining member, for example, the first refining member 20 including the first refining body portion 1022 / 1022A′, can be fixed to the support frame 66 of the refiner 10 and define a non-rotating stator member. Another refining member, for example, the second refining member 30 including the second refining body portion 1032 / 1032′, can be fixed to a support 70, which rotates with a shaft 72 and defines a rotor associated with the main support frame, such that rotation of the rotor effects movement of the second refining member 30 relative to the first refining member 20. The first and second refining body portions 1022 / 1022', 1032 / 1032' each include multiple sections (not shown; see 22A-22C and 32A-32C in Figures 2 and 3), which may be bolted or otherwise attached together to form a disk-shaped refining body portion including respective radially inner edges 1023, 1023' and 1033, 1033' and radially outer edges 1027, 1027' and 1037, 1037'.

[0069] Referring to FIG. 19A, the refining surfaces 1024, 1034 each include a plurality of elongated refiner bars 1026, 1036, each including a first refiner bar 1026A, 1036A and a second refiner bar 1026B, 1036B, which are refined by respective first refiner grooves 1028A, 1038A and second refiner grooves 1028B, 1038B. (The first and second refiner bars 1026A / 1036A and 1026B / 1036B may also be referred to herein as first and second refiner bar elements.) In some examples, the first and second refiner grooves 1028A, 1028B and 1038A, 1038B may have widths of about 2.0 mm to about 6.0 mm (not shown; see W in FIGS. 4A and 5A ). G 7), and the first and second refiner bars 1026A, 1026B and 1036A, 1036B can have a width (not shown; see W in FIG. 7) of about 2.0 mm to about 8.0 mm. 26 Each of these ranges includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, and 6.0 mm for the range of about 2.0 mm to about 6.0 mm, and 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, and 8.0 mm for the range of about 2.0 mm to about 8.0 mm. The refiner bars 1026, 1036 can be angled at various angles on their respective refining surfaces 1024, 1034, and each section of the refining body 1022, 1032 can include one or more segments (not labeled) of refiner bars 1026, 1036 angled in different directions (not shown; see Figures 2 and 3).

[0070] Each of the first and second refiner bars 1026, 1036 extends radially outward from a radially inward location, i.e., a radially inner edge 1023, 1033, toward a radially outer edge 1027, 1037 of the respective refining body 1022, 1032. Specifically, each of the first refiner bars 1026A, 1036A extends radially outward from a first radially inward location P on the refining surface 1024, 1034. 1000 to a first radially outward position P on the refining surfaces 1024, 1034 2000 Each of the second refiner bars 1026B, 1036B extends from a second radially inward position on the refining surfaces 1024, 1034 to a second radially outward position P on the refining surfaces 1024, 1034, as described herein. 3000 and a second radially outward position P 3000 is the first radially outward position P in the general direction of travel of the wood fibers 2000 It is possible for the first radially inward position P to be closer to the outermost parts of the refining bodies 1022, 1032, e.g., the radially outer edges 1027, 1037, than to the first radially inward position P 1000 may include a position at or near the radially inner edge 1023, 1033. In some embodiments, the second refiner bar 1026B, 1036B is positioned such that the second radially inward position P of the second refiner bar 1026B, 1036B is positioned at a position near the first radially outward position P of the first refiner bar 1026A, 1036A. 2000 and the second refiner bars 1026B, 1036B are positioned at the first radially outward position P 2000 to a second radially outward position P 3000The first refiner bar 1026A, 1036A may be integral with the first refiner bar 1026A, 1036A so as to extend to the first refiner bar 1026B, 1036B. In other embodiments (not shown), the first refiner bar 1026A, 1036A may be radially separated from the second refiner bar 1026B, 1036B by a space. The second refiner bar 1026B, 1036B has a longitudinal length L of about 0.6 cm to about 10 cm, preferably about 2 cm to about 10 cm. 1000 As described above, the refining surfaces 1024, 1034 may include dams (not shown; see 29 and 39 in Figures 4A, 5A, and 7) disposed within at least a portion of the first refiner grooves 1028A, 1038A, and the dams may include a height substantially the same as or less than the height of the adjacent first refiner bars 1026A, 1036A.

[0071] With continued reference to FIG. 19A, the first refiner bars 1026A, 1036A are Floor F of adjacent first refiner groove sections 1028A, 1038A 1000 A first height H extending upward from 1000 In some examples, the first height H 1000 can be the maximum height of the first refiner bars 1026A, 1036A. The first refiner bars 1026A, 1036A can be positioned, for example, at a first radially inward position P 1000 and a first radially outward position P 2000 Between the first height H 1000 The first height H of the first refiner bars 1026A, 1036A can extend substantially horizontally, such that the first height H of the first refiner bars 1026A, 1036A can be substantially constant along the longitudinal length (not labeled) of the first refiner bars 1026A, 1036A. In some examples, the first height H of the first refiner bars 1026A, 1036A can extend substantially horizontally, such that the first height H of the first refiner bars 1026A, 1036A can be substantially constant along the longitudinal length (not labeled) of the first refiner bars 1026A, 1036A. 1000 The adjacent first refiner grooves 1028A and 1038A have floors F 1000 When measured from 、4 .0mm ~10.0 mm (±0.5 mm), which range includes all values ​​and subranges therebetween, including, for example, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm.

[0072] The second refiner bars 1026B, 1036B are positioned on the floors F of the adjacent second refiner grooves 1028B, 1038B. 2000 A second height H extending upward from 2000 and the second height H 2000 is the minimum height of the second refiner bars 1026B, 1036B, and the second radially inward position of the second refiner bars 1026B, 1036B, e.g., P 2000 (first and second heights H 1000 , H 2000 (sometimes referred to herein as first and second bar heights). In some embodiments, the floor F of adjacent second refiner grooves 1028B, 1038B 2000 a second height H of the second refiner bars 1026B, 1036B extending upward from 2000 can be greater than zero, as shown by the solid line in FIG. 19A. For example, the second height H 2000 is 2 .0mm ~4 The second height H can be 0.0 mm (±0.2 mm), which range includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm, 3.0 mm, 3.2 mm, 3.4 mm, 3.6 mm, 3.8 mm, and 4.0 mm. In other embodiments, the second height H 2000 is slightly greater than zero, e.g., second refiner bar 1026B, 1036B at its minimum height is positioned so that it is flush with the floor F of the adjacent second refiner groove 1028B, 1038B, as shown by the dashed line in FIG. 19A. 2000 A level or floor slightly above F 2000 It can be flush with the

[0073] The second height H of the second refiner bars 1026B, 1036B 2000 is the first height H of the first refiner bars 1026A, 1036A. 1000 At least Also 0 In some instances, the second height H 2000 is the first height H 1000 In some particular examples, the second height H of the second refiner bars 1026B, 1036B can be at least 0.7 mm (±0.05 mm) smaller than 2000 The adjacent second refiner groove sections 1028B and 1038B have floors F 2000 The first height H when measured from 1000 twist Also 0 .35mm ~7 The second height H can be as small as 0.05 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.35 mm, 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, and 7.0 mm. In other specific examples, the second height H 2000 is the first height H 1000 twist Also 0 .7mm ~7 The second height H can be as small as 0.0 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.7 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, and 7.0 mm. In a further specific example, the second height H 2000 is the first height H 1000 twist Also 0 .7mm ~5 0.0mm (±0.05mm) smaller, or the first height H 1000 twist Also 2 .0mm ~3The second height H can be as small as 0.0 mm (±0.05 mm). Each of these ranges includes all values ​​and subranges therebetween, for example, 0.7 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, and 4.5 mm for the range of about 0.7 mm to about 5.0 mm, and 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, and 3.0 mm for the range of about 2.0 mm to about 3.0 mm. 2000 In embodiments where the first height H is slightly greater than zero, 1000 and the second height H 2000 The difference between the first height H of the first refiner bars 1026A, 1036A can be substantially the entire height of the first refiner bars 1026A, 1036A. For example, 1000 is about 10.0 mm, the second height H of the second refiner bars 1026B, 1036B 2000 is the first height H 1000 It is possible to make the thickness of the slit 10.0 mm smaller than the thickness of the slit 10.0 mm.

[0074] As shown in FIG. 19A, in some examples, the second refiner bars 1026B, 1036B are positioned at a first radially outward position P 2000 to a second radially outward position P 3000 In some particular examples, the height of the second refiner bar 1026B, 1036B may be substantially continuously downwardly sloping along at least a portion of the second refiner bar 1026B, 1036B extending between the longitudinal length L of the second refiner bar 1026B, 1036B. 1000 For example, the second refiner bars 1026B, 1036B may be positioned at a first radially outward position P 2000 The first refiner bars 1026A and 1036A are adjacent to each other and have a first height H 1000, in which case the second refiner bars 1026B, 1036B may have a maximum height (not separately labeled) that is substantially the same as the first radially outward position P 2000 to a second radially outward position P 3000 The second refiner bars 1026B, 1036B have a second (minimum) height H 2000 is the second radially outward position P 3000 It is possible for the nucleotide sequence to be located adjacent to the nucleotide sequence.

[0075] In some examples, the first and second refining members 20, 30, including the first and second refining body portions 1022, 1032, can be arranged so that the first refining surface 1024 faces the second refining surface 1034 (not shown; see, for example, Figures 1, 8 and 9), in which case the first refining member 20 is spaced apart from the second refining member 30 to define a refining space (see 60 in Figure 1) between the respective refining surfaces 1024, 1034, as described in detail herein. At least a portion of the refiner bars 1026 of the first refining body portion 1022 can be positioned directly opposite, i.e., facing, at least a portion of the refiner bars 1036 of the second refining body portion 1032 so as to define a gap (see FIGS. 8 and 9 ) between the opposing portions of the refiner bars 1026, 1036. Specifically, at least a portion of the first refiner bar 1026A of the first refining body portion 1022 can be positioned directly opposite, i.e., facing, at least a portion of the first refiner bar 1036A of the second refining body portion 1032, and at least a portion of the second refiner bar 1026B of the first refining body portion 1022 can be positioned directly opposite, i.e., facing, at least a portion of the second refiner bar 1036B of the second refining body portion 1032.

[0076] A slurry of wood pulp containing wood fibers, as shown in FIG. 1 and described above. is supplied to the frame 66 of the refiner 10, an axial force or pressure can be applied to one or both of the refining members 20, 30, thereby adjusting the size of the gap defined between the first refining member 20 and the second refining member 30. The first refiner bars 1026A, 1036A can be adapted to refine the wood fibers in the pulp slurry, while the second refiner bars 1026B, 1036B can be adapted to break down or separate the fiber bundles. The first height H of the first refiner bars 1026A, 1036A 1000 is the second height H of the second refiner bars 1026B and 1036B. 2000 Because the height of the first refiner bars 1026A, 1036A is greater than the height of the first refiner bars 1028A, 1038A, the wood fibers are subjected to high-intensity shear and compressive forces as the fibers pass through a portion of the refining space (e.g., a refining zone as described above) at least partially defined by the first refiner grooves 1028A, 1038A. The first refiner bars 1026A, 1036A interact with each other and with conventional refiner bars to refine a significant number of the wood fibers in the wood pulp. As the fibers pass through a portion of the refining space (e.g., a deflaking zone as described above) at least partially defined by the second refiner grooves 1028B, 1038B, the intensity of the force applied to the fibers decreases in response to the reduced height, which is believed to break down or separate the multiple wood fiber bundles formed during refining without further refining or only minimally refining the fibers.

[0077] In this example, the gap between the opposing portions of the second refiner bars 1026B, 1036B is 、0 .9mm ~2It can be set to 0.0 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.9mm, 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mm, 7.0mm, 7.5mm, 8.0mm, 8.5mm, 9.0mm, 9.5mm, 10.0mm, 10.5mm, 11.0mm, 11.5mm, 12.0mm, 12.5mm, 13.0mm, 13.5mm, 14.0mm, 14.5mm, 15.0mm, 15.5mm, 16.0mm, 16.5mm, 17.0mm, 17.5mm, 18.0mm, 18.5mm, 19.0mm, 19.5mm, and 20.0mm. In embodiments in which the second refiner bar 1026B and / or 1036B slopes downward substantially continuously along at least a portion of the second refiner bar 1026B, 1036B, the gap extends radially outward along at least one section of the second refiner bar 1026B, 1036B, i.e., from a second radially inward position (e.g., P 2000 ) to a second radially outward position P 3000 In some examples, the gap can increase substantially along the longitudinal length L of the second refiner bars 1026B, 1036B. 1000 To stop refining the fibers and begin deflaking, the second (minimum) height H of the second refiner bars 1026B, 1036B can be increased along the entire 2000 is the first height H of the first refiner bars 1026A, 1036A. 1000 At least Also 0 It is thought that it should be 0.35mm (±0.05mm) smaller.

[0078] In another example, one of the refining bodies 1022, 1032 shown in FIG. 19A can be paired with a conventional refining body (not shown; see 132 in FIG. 8) including conventional refiner bars having a uniform height along substantially the entire longitudinal length. For example, the first refining member 20 may include the first refining body 1022, and the second refining member 30 may include a conventional refining body. The refining members 20, 30 may be arranged such that at least a portion of the first and second refiner bars 1026A, 1026B are directly opposite at least a portion of the conventional refiner bars such that a gap (see FIGS. 8 and 9) is defined between the opposing portions. The refiner bars 1026A and 1026B may be positioned facing each other, i.e., facing each other, with the refiner bars positioned facing each other. As described herein, a wood pulp slurry may be provided, and an axial force or pressure may be applied to one or both of the refiner members 20, 30 to adjust the gap size, with the first refiner bar 1026A adapted to refine the wood fibers in the pulp slurry and the second refiner bar 1026B adapted to break down or separate the fiber bundles. In this example, the gap between the opposing portions of the second refiner bar 1026B and the conventional refiner bar is 、0 .9mm ~1 The gap can be 0.0 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.9 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm. In embodiments in which the second refiner bar 1026B is angled, as described herein, the gap can increase in the radially outward direction along at least one section of the second refiner bar 1026B, and can increase along the substantially longitudinal length L of the second refiner bar 1026B. 1000In this example, to stop refining the fibers and begin deflaking, the second (minimum) height H of the second refiner bar 1026B is increased. 2000 is the first height H of the first refiner bar 1026A / 1036A 1000 At least Also 0 It is thought that it should be 0.7mm smaller (±0.05mm).

[0079] In both examples, for refining to occur, a gap between opposing portions of the refiner bars (e.g., between opposing portions of the first refiner bar 1026A, 1036A, or between opposing portions of the first refiner bar 1026A / 1036A and a conventional refiner bar) must be present. is 0 It is believed that the gap in the refining zone should be less than 0.9mm (±0.05mm). is 0 In some specific cases, the gap may be smaller than 0.7mm (±0.05mm). is 0 .1mm ~0 The gap width can be 0.5 mm (±0.05 mm), which range includes all values ​​and subranges therebetween, including, for example, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, and 0.5 mm. Also, for deflaking to occur, the gap width (e.g., between opposing portions of the second refiner bars 1026B, 1036B, or between opposing portions of the second refiner bars 1026B / 1036B and a conventional refiner bar) can be 0.5 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, and 0.5 mm. is 0 .9mm ~2It is contemplated that the gap should be approximately 0.0 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, and 2.0 mm. As explained above, the gap along at least a portion of the second refiner bar 1026B / 1036B can be much larger than about 2.0 mm, for example, up to about 20.0 mm in some cases. This larger gap can be achieved by adjusting the height H of the refiner bars 1026A, 1036A, 1026B, 1036B. 1000 , H 2000 The position of the refining body portion can be adjusted as described herein to maintain the gap at a desired value as the refining surface begins to wear. Specifically, embodiments in which the second refiner bars 1026B, 1036B slope downward substantially continuously along at least a portion of each second refiner bar 1026B, 1036B may be configured such that the transition between the refining zone and the deflaking zone is approximately equal to the longitudinal length L of the second refiner bars 1026B, 1036B, such that a gap of about 0.9 mm to about 2.0 mm for deflaking can be maintained over the life of the refining element. 1000 allowing the slit to shift radially outward along It is thought that this is the case.

[0080] Referring to FIG. 19B, the refining body portions 1022', 1032' include respective refining surfaces 1024', 1034', which may each include a plurality of elongated refiner bars 1026', 1036', including a first refiner bar 1026A', 1036A', a second refiner bar 1026B', 1036B', a third refiner bar 1026C, 1036C, and a fourth refiner bar 1026D, 1036D. The first and second refiner bars 1026A', 1036A', 1026B', 1036B' can be substantially similar to the first and second refiner bars 1026A, 1036A, 1026B, 1036B illustrated in FIG. 19A and described herein. The first refiner bars 1026A', 1036A' can be separated from one another by first refiner grooves 1028A', 1038A', and the second refiner bars 1026B', 1036B' can be separated from one another by second refiner grooves 1028B', 1038B'. The third refiner bars 1026C, 1036C can be separated from each other by third refiner grooves 1028C, 1038C, and the fourth refiner bars 1026D, 1036D can be separated from each other by fourth refiner grooves 1028D, 1038D.

[0081] Each of the first refiner bars 1026A′, 1036A′ is positioned at a first radially inward position P on the refining surface 1024′, 1034′. 1000’ to a first radially outward position P 2000’ Each of the second refiner bars 1026B′, 1036B′ can extend from a second radially inward position on the refining surface 1024′, 1034′ to a second radially outward position P 1 on the refining surface 1024′, 1034′, as described herein. 3000’Each of the third refiner bars 1026C, 1036C can extend from a third radially inward position on the refining surface 1024′, 1034′ to a third radially outward position P on the refining surface 1024′, 1034′, as described herein. 4000 Each of the fourth refiner bars 1026D, 1036D can extend from a fourth radially inward position on the refining surface 1024′, 1034′ to a fourth radially outward position P on the refining surface 1024′, 1034′, as described herein. 5000 The fourth radially outward position P 5000 are the first, second and third radially outward positions P 2000’ , P 3000’ and P 4000 The second and fourth refiner bars 1026B' / 1036B' and 1026D / 1036D can be located near the outermost parts of the refining body portions 1022', 1032', e.g., near the radially outer edges 1027', 1037', rather than the outermost parts. The second and fourth refiner bars 1026B' / 1036B' and 1026D / 1036D can have respective longitudinal lengths L of about 0.6 cm to about 10 cm, preferably about 2 cm to about 10 cm. 1000’ , L 2000 In some examples, the first and / or second refiner bars 1026A', 1036A', 1026B', 1036B' may extend radially outward a shorter distance than the first and second refiner bars 1026A, 1036A, 1026B, 1036B. As described above, the refining surface 1024', 1034' may include dams (not shown; see 29 and 39 in Figures 4B and 5B) disposed within at least a portion of the first and third refiner grooves 1028A' / 1038A' and 1028C / 1038C, and the dams may include a height substantially the same as or less than the height of the adjacent first and / or third refiner bars 1026A' / 1036A' and 1026C / 1036C.

[0082] In some embodiments, as shown in FIG. 19B, the second refiner bar 1 The first refiner bar 1026A', 1036A' can be integral with the first refiner bar 1026A', 1036A', the third refiner bar 1026C, 1036C can be integral with the second refiner bar 1026B', 1036B', and / or the fourth refiner bar 1026D, 1036D can be integral with the third refiner bar 1026C, 1036C. For example, when the first and second refiner bars 1026A' / 1036A' and 1026B' / 1036B' are integral with each other, the second radially inward position of the second refiner bar 1026B', 1036B' is greater than the first radially outward position P of the first refiner bar 1026A', 1036A'. 2000’ and the second refiner bars 1026B′, 1036B′ are positioned at a first radially outward position P 2000’ to a second radially outward position P 3000’ When the second and third refiner bars 1026B′ / 1036B′ and 1026C / 1036C are integral with one another, the third radially inward position of the third refiner bar 1026C, 1036C can extend to the second radially outward position P of the second refiner bar 1026B′, 1036B′. 3000’ and the third refiner bars 1026C, 1036C are positioned at a second radially outward position P 3000’ to a third radially outward position P 4000 When the third and fourth refiner bars 1026C / 1036C and 1026D / 1036D are integral with one another, the fourth radially inward position of the fourth refiner bar 1026D, 1036D can extend to the third radially outward position P of the third refiner bar 1026C, 1036C. 4000 and the fourth refiner bars 1026D, 1036D are positioned at a third radially outward position P 4000to a fourth radially outward position P 5000 In other embodiments (not shown), the first refiner bar 1026A', 1036A' can be radially separated from the second refiner bar 1026B', 1036B' by a fixed space, the second refiner bar 1026B', 1036B' can be radially separated from the third refiner bar 1026C, 1036C by a fixed space, and / or the third refiner bar 1026C, 1036C can be radially separated from the fourth refiner bar 1026D, 1036D by a fixed space.

[0083] Continuing to refer to FIG. 19B, the first and third refiner bars 1026A′ / 1036A′ and 1026C / 1036C are aligned with the floors F of the respective adjacent first and third refiner grooves 1028A′ / 1038A′ and 1028C / 1038C. 1000’ , F 3000 Each first height H 1000’ and the third height H 3000 The first and third heights H 1000’ , H 3000 can be the maximum height of the first and third refiner bars 1026A' / 1036A' and 1026C / 1036C, respectively. In some examples, the first and third refiner bars 1026A' / 1036A' and 1026C / 1036C can be the maximum height of the first and third refiner bars 1026A' / 1036A' and 1026C / 1036C, respectively. 1000’ , H 3000 may be substantially constant along the longitudinal lengths (not labeled) of the first and third refiner bars 1026A' / 1036A' and 1026C / 1036C, e.g., the first radially inward position P 1000’ and a first radially outward position P 2000’ and a third radially inward position of the third refiner bar 1026C, 1036C, e.g., P 3000’ and a third radially outward position P4000 In some examples, the first and third heights H of the first and third refiner bars 1026A' / 1036A' may extend substantially horizontally between the first and third heights H 1000’ , H 3000 are the floors F of the respective adjacent first and third refiner grooves 1028A' / 1038A' and 1028C / 1038C. 1000’ , F 3000 When measured from 、4 .0mm ~1 0.0 mm (±0.5 mm), this range includes all values ​​and subranges therebetween, including, for example, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm.

[0084] The second and fourth refiner bars 1026B' / 1036B' and 1026D / 1036D are aligned with the floors F of the respective adjacent second and fourth refiner grooves 1028B' / 1038B' and 1028D / 1038D. 2000’ , F 4000 Each second height H 2000’ and the fourth height H 4000 The second height H 2000’ is the minimum height of the second refiner bars 1026B′, 1036B′, and the second radially inward position of the second refiner bars 1026B′, 1036B′, e.g., P 2000’ The fourth height H 4000 is the minimum height of the fourth refiner bar 1026D, 1036D, and is the fourth radially inward position of the fourth refiner bar 1026D, 1036D, e.g., P 4000 In some embodiments, the floor F of the adjacent second refiner grooves 1028B′, 1038B′ is spaced apart from the 2000’ The second height H of the second refiner bars 1026B′, 1036B′ extending upward from 2000’, and / or the floor F of the adjacent fourth refiner groove section 1028D, 1038D 4000 The fourth height H of the fourth refiner bars 1026D, 1036D extending upward from 4000 can be greater than zero, as shown by the solid line in FIG. 19B. For example, the second height H 2000’ and / or fourth height H 4000 teeth 、2 .0mm ~4 The second height H may be 0.0 mm (±0.2 mm), which range includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm, 3.0 mm, 3.2 mm, 3.4 mm, 3.6 mm, 3.8 mm, and 4.0 mm. In other embodiments, the second height H 2000’ and / or fourth height H 4000 can be slightly greater than zero, for example, the second refiner bar 1026B′, 1036B′ and / or the fourth refiner bar 1026D, 1036D at their minimum heights are spaced apart from the floor F of the respective adjacent second or fourth refiner groove 1028B′ / 1038B′, 1028D / 1038D, as shown by the dashed lines in FIG. 19B. 2000’ , F 4000 It can be slightly above or flush with the surface.

[0085] The second height H of the second refiner bars 1026B′, 1036B′ 2000’ and / or the fourth height H of the fourth refiner bars 1026D, 1036D 4000 are the first heights H of the first refiner bars 1026A′ and 1036A′, respectively. 1000’ and / or the third height H of the third refiner bars 1026C, 1036C 3000 At least Also 0 In some instances, the second height H 2000’ and the fourth height H 4000 are the first height H 1000’ and the third height H 3000In some particular examples, the second height H of the second refiner bars 1026B′, 1036B′ can be at least 0.70 mm (±0.05 mm) smaller than the 2000’ The adjacent second refiner grooves 1028B' and 1038B' have floors F 2000’ and / or the fourth height H of the fourth refiner bar 1026D, 1036D when measured from 4000 The adjacent fourth refiner groove sections 1028D and 1038D have floors F 4000 When measured from the first height H 1000’ and the third height H 3000 twist Also 0 .35mm ~7 The second height H can be as small as 0.05 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.35 mm, 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, and 7.0 mm. In other specific examples, the second height H 2000’ and the fourth height H 4000 are the first height H 1000’ and the third height H 3000 twist Also 0 .7mm ~7 The range can be as small as 0.0 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.7 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, and 7.0 mm. In a further specific example, the second height 2000’ and the fourth height H 4000 are the first height H 1000’ and the third height H 3000 twist Also 0 .7mm ~5 0.0mm (±0.05mm), or the first height H 1000’ and the third height H 3000 twist Also 2 .0mm ~3The second and / or fourth heights H may be as small as 0.0 mm (±0.05 mm). Each of these ranges includes all values ​​and subranges therebetween, for example, 0.7 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, and 4.5 mm for the range of about 0.7 mm to about 5.0 mm, and 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, and 3.0 mm for the range of about 2.0 mm to about 3.0 mm. 2000’ , H 4000 In embodiments where H is slightly greater than zero, the first and second heights H 1000’ , H 2000’ and / or the third and fourth heights H 3000 , H 4000 The difference between the first and third heights H can be substantially the entire height of the first and / or third refiner bars 1026A′ / 1036A′ and 1026C / 1036C. For example, the difference between the first and third heights H 1000’ , H 3000 is approximately 10.0 mm, the second and fourth heights H 2000’ , H 4000 are the first and third heights H 1000’ , H 3000 It is possible to make the thickness of the slit 10.0 mm smaller than the thickness of the slit 10.0 mm.

[0086] 19B, in some examples, the second refiner bar 1026B', 1036B' and / or the fourth refiner bar 1026D, 1036D can be substantially continuously downwardly sloped along at least a portion of the respective refiner bar 1026B', 1036B', 1026D, 1036D. For example, the second refiner bar 1026B', 1036B' can be sloped downwardly at a first radially outward position P 2000’ to a second radially outward position P 3000 and / or the fourth refiner bar 1026D, 1036D may be sloped downwardly substantially continuously along at least a portion extending between the third radially outward position P4000 to a fourth radially outward position P 5000 In some particular examples, the height of second refiner bar 1026B′, 1036B′ and / or fourth refiner bar 1026D, 1036D is substantially equal to or greater than the longitudinal length L of the respective refiner bars. 1000’ , L 2000 For example, the second refiner bars 1026B′, 1036B′ may be positioned at a first radially outward position P 2000’ and the first height H of the first refiner bars 1026A′, 1036A′ 1000’ and the second refiner bars 1026B′, 1036B′ may have a maximum height (not separately labeled) that is at a position that is substantially the same as the first radially outward position P 2000’ to a second radially outward position P 3000’ The fourth refiner bars 1026D, 1036D similarly slope downwardly substantially continuously to a third radially outward position P 4000 and the third refiner bars 1026C and 1036C are adjacent to the third height H 3000 and the fourth refiner bar 1026D, 1036D may have a maximum height (not separately labeled) that is at a position that is substantially the same as the third radially outward position P 4000 to a fourth radially outward position P 5000 The second refiner bars 1026B′, 1036B′ have a second (minimum) height H 2000’ is the second radially outward position P 3000’ and the fourth refiner bar 1026D, 1036D may be located adjacent to the fourth (minimum) height H 4000 is the fourth radial outward position P 5000 It is possible for the nucleotide sequence to be located adjacent to the nucleotide sequence.

[0087] In some examples, the first and second refining members 20, 30, including the first and second refining body portions 1022′, 1032′, can be arranged so that the first and second refining surfaces 1024′, 1034′ face each other (not shown; see, e.g., FIGS. 1, 8, and 9) and define a refining space (see 60 in FIG. 1), as described in detail herein. At least a portion of the refiner bars 1026′ of the first refining body portion 1022′ are positioned directly opposite, i.e., facing, at least a portion of the refiner bars 1036′ of the second refining body portion 1032′ so as to define a gap (see FIGS. 8 and 9) between the opposing portions of the refiner bars 1026′, 1036′. Specifically, at least a portion of the first refiner bar 1026A' of the first refining body portion 1022' can be positioned so as to be directly opposite, i.e., facing, at least a portion of the first refiner bar 1036A' of the second refining body portion 1032', at least a portion of the second refiner bar 1026B' can be positioned so as to be directly opposite, i.e., facing, at least a portion of the second refiner bar 1036B', at least a portion of the third refiner bar 1026C can be positioned so as to be directly opposite, i.e., facing, at least a portion of the third refiner bar 1036C, and at least a portion of the fourth refiner bar 1026D can be positioned so as to be directly opposite, i.e., facing, at least a portion of the fourth refiner bar 1036D.

[0088] As shown in FIG. 1 and described above, when a slurry of wood pulp containing wood fibers is fed into the frame 66 of the refiner 10, an axial force or pressure can be applied to one or both of the refining members 20, 30 to adjust the size of the gap defined between the first refining member 20 and the second refining member 30. The first and third refiner bars 1026A' / 1036A' and 1026C / 1036C can be adapted to refine the wood fibers in the pulp slurry, while the second and fourth refiner bars 1026B' / 1036B' and 1026D / 1036D can be adapted to break down or separate fiber bundles. The first and third heights H of the first and third refiner bars 1026A' / 1036A' and 1026C / 1036C can be adjusted to adjust the size of the gap defined between the first and second refining members 20, 30. 1000’ and H 3000 are the second and fourth heights H of the second and fourth refiner bars 1026B' / 1036B' and 1026D / 1036D, respectively. 2000’ and H 4000 Because the diameters of the first and third refiner bars 1026A' / 1036A' and 1026C / 1036C are greater than 1 / 2 mm, the wood fibers are subjected to high-intensity shear and compressive forces as the fibers pass through a portion of the refining space (e.g., the first and second refining zones as described above) that is at least partially defined by the first and third refiner grooves 1028A' / 1038A' and 1028C / 1038C. The first and third refiner bars 1026A' / 1036A' and 1026C / 1036C interact with each other to refine a significant number of the wood fibers in the wood pulp. As the fibers pass through a portion of the refining space (e.g., the first and second deflaking zones as described above) at least partially defined by the second and fourth refiner grooves 1028B' / 1038B' and 1028D / 1038D, the intensity of the force applied to the fibers decreases in response to the reduced height, which is believed to break down or separate the multiple wood fiber bundles formed during refining without further refining or only minimally refining the fibers.

[0089] In this example, the gap between the opposing portions of the second refiner bars 1026B′, 1036B′ and the opposing portions of the fourth refiner bars 1026D, 1036D is 、0 .9mm ~2 The range can be, for example, 0.9 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, The ranges include 3.5mm, 4.0mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mm, 7.0mm, 7.5mm, 8.0mm, 8.5mm, 9.0mm, 9.5mm, 10.0mm, 10.5mm, 11.0mm, 11.5mm, 12.0mm, 12.5mm, 13.0mm, 13.5mm, 14.0mm, 14.5mm, 15.0mm, 15.5mm, 16.0mm, 16.5mm, 17.0mm, 17.5mm, 18.0mm, 18.5mm, 19.0mm, 19.5mm, and 20.0mm, including all values ​​and subranges therebetween. In examples where one or more of the second and fourth refiner bars 1026B′ / 1036B′ and 1026D / 1036D are substantially continuously downwardly sloped along at least a portion, the gap extends radially outward along at least one section of the second refiner bar 1026B′, 1036B′, i.e., from a second radially inward position (e.g., P 2000’ ) to a second radially outward position P 3000’ and / or the gap can increase in a radially outward direction along at least one section of the fourth refiner bar 1026D, 1036D, i.e., at a fourth radially inward position (e.g., P 4000 ) to a fourth radially outward position P 5000 In some examples, the gap can increase along the substantially longitudinal length L of the second and / or fourth refiner bars 1026B′ / 1036B′ and 1026D / 1036D, respectively.1000’ and / or L 2000 To stop refining the fibers and begin deflaking, the second (minimum) height H of the second refiner bars 1026B′, 1036B′ can be increased along the entire 2000’ and the fourth (minimum) height H of the fourth refiner bars 1026D and 1036D. 4000 are the first heights H of the first refiner bars 1026A′ and 1036A′, respectively. 1000’ and the third height H of the third refiner bars 1026C and 1036C. 3000 At least Also 0 It is thought that it should be 0.35mm (±0.05mm) smaller.

[0090] In another example, one of the refining bodies 1022′, 1032′ shown in FIG. 19B can be paired with a conventional refining body (not shown; see 132 in FIG. 8) including refiner bars with a uniform height along substantially the entire longitudinal length. For example, the first refining member 20 can include the first refining body 1022′, and the second refining member 30 can include a conventional refining body. The refining members 20, 30 can be arranged facing each other, with at least a portion of the first, second, third, and fourth refiner bars 1026A′, 1026B′, 1026C, 1026D positioned directly opposite, i.e., facing, at least a portion of the conventional refiner bars to define a gap (see FIGS. 8 and 9) between the opposing portions. As described herein, a wood pulp slurry is provided, and an axial force or pressure can be applied to one or both of the refining members 20, 30 to adjust the gap size, with the first and third refiner bars 1026A', 1026C adapted to refine wood fibers in the pulp slurry and the second and fourth refiner bars 1026B', 1026D adapted to break down or separate fiber bundles. In this example, the gap between the opposing portions of the conventional refiner bars and the second and fourth refiner bars 1026B', 1026D is 、0 .9mm ~1 The gap can be 0.0 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.9 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm. In embodiments where the second and / or fourth refiner bars 1026B', 1026D are angled, the gap can be adjusted to accommodate the angle of the refiner bars as described herein. The refiner bars 1026B′, 1026D may increase in a radially outward direction along at least one section thereof, and the second and / or fourth refiner bars 1026B′, 1026D may increase in a substantially longitudinal length L 1000’ , L 2000 In this example, to stop refining the fibers and begin deflaking, the second (minimum) height H of the second refiner bar 1026B' / 1036B' is increased. 2000’ and the fourth (minimum) height H of the fourth refiner bar 1026D / 1036D. 4000 are the first height H of the first refiner bar 1026A′ / 1036A′, respectively. 1000’ and the third height H of the third refiner bars 1026C and 1036C. 3000 At least Also 0 It is thought that it should be 0.7mm (±0.05mm) smaller.

[0091] In both examples, for refining to occur, a gap between opposing portions of the refiner bars (e.g., between opposing portions of the first and third refiner bars 1026A', 1036A' and 1026C, 1036C, or between opposing portions of conventional refiner bars and the first and third refiner bars 1026A' / 1036A' and 1026C / 1036C) must be present. is 0 It is believed that the gap in the refining zone should be less than 0.9mm (±0.05mm). is 0 In some specific cases, the gap may be smaller than 0.7mm (±0.05mm). is 0 .1mm ~0The gap width can be 0.5 mm (±0.05 mm), which range includes all values ​​and subranges therebetween, including, for example, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, and 0.5 mm. Also, for deflaking to occur, a gap (e.g., between opposing portions of the second and fourth refiner bars 1026B', 1036B' and 1026D, 1036D, or between opposing portions of conventional refiner bars and the second and fourth refiner bars 1026B' / 1036B' and 1026D / 1036D) must be less than 0.5 mm. is 0 .9mm ~2 It is contemplated that the height H of each refiner bar 1026A', 1036A', 1026B', 1036B', 1026C, 1036D, 1036D should be within 0.0 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, and 2.0 mm. As described herein above, the height H of each refiner bar 1026A', 1036A', 1026B', 1036B', 1026C, 1036C, 1026D, 1036D 1000’ , H 2000’ , H 3000 , H 4000 A gap greater than about 2.0 mm can be used to account for wear that reduces the gap. The position of the refining body section can be adjusted as described herein to maintain the gap at a desired value as the refining surface begins to wear. Specifically, embodiments in which the second and / or fourth refiner bars 1026B' / 1036B' and 1026D / 1036D slope downward substantially continuously along at least a portion of the refiner bars 1026B' / 1036B' and 1026D / 1036D can be configured such that the transition between the refining zone and the deflaking zone is adjusted along the longitudinal length L of the second and / or fourth refiner bars 1026B' / 1036B' and 1026D / 1036D such that a gap of about 0.9 mm to about 2.0 mm for deflaking can be maintained over the life of the refining element. 1000’ , L 2000It is believed that this allows the ion beam to shift radially outward along the

[0092] 13 and 14 are plan views of a portion of a first refining surface 224 of a first refining body 222 and a second refining surface 234 of a second refining body 232, respectively, according to another embodiment of the present disclosure. With reference to FIGS. 1, 13, and 14, the first and second refining bodies 222, 232 are refining members (e.g., disc refiners, respectively) for use in a pulp refiner, such as the disc refiner 10 shown in FIG. 1, as described herein. Each of the refining members 20, 30, including the first and second refining body portions 222, 232, respectively, can be associated with a main support frame, which includes a fixed support frame 66 fixed to the first housing section 12 and a movable support frame 68. One refining member (e.g., the first refining member 20 including the first refining body portion 222) can be fixed to the support frame 66 of the refiner 10 and define a non-rotating stator member. Another refining member (e.g., the second refining member 30 including the second refining body portion 232) can be fixed to a support 70, which rotates with a shaft 72 and defines a rotor associated with the main support frame, such that rotation of the rotor effects movement of the second refining member 30 relative to the first refining member 20.

[0093] As shown in FIG. 13 , first refining body 222 includes multiple sections (not separately labeled; see FIGS. 2 and 3 ), which may be bolted or otherwise attached together to form disk-shaped refining body 222 including radially outer edge 227. First refining surface 224 includes a plurality of elongated first refiner bars 226, which are separated from one another by first refiner grooves 228. First refiner bars 226 extend radially outward from radially inner location 223 toward radially outer edge 227 of first refining body 222. First refiner bars 226 can be angled at various angles, as shown in Figure 13, and each section of refining body 222 can include one or more segments (not labeled) of refiner bars 226 that are angled in different directions. First refining body 222 further includes one or more annular rows or rings of teeth 400 positioned between first refiner bars 226 and radially outer edge 227 of first refining body 222. Although not shown in Figure 13, it is understood that other sections (not labeled) of first refining body 222 will similarly include refiner bars 226, refiner grooves 228, and teeth 400.

[0094] As shown in FIG. 14 , second refining body 232 includes multiple sections (not separately labeled; see FIGS. 2 and 3 ), which may be bolted or otherwise attached together to form disk-shaped refining body 232 including radially outer edge 237. Second refining surface 234 includes a plurality of elongated second refiner bars 236, which are separated from one another by second refiner grooves 238. Second refiner bars 236 extend radially outward from radially inner location 233 toward radially outer edge 237 of second refining body 232. The second refiner bars 236 can be angled at various angles, as shown in FIG. 14 , and each section of the refining body 232 can include one or more segments (not labeled) of refiner bars 236 that are angled in different directions. The second refining body 232 further includes one or more annular rows or rings of teeth 400 positioned between the second refiner bars 236 and the radially outer edge 237 of the second refining body 232. Although not shown in FIG. 14 , it is understood that other sections (not labeled) of the second refining body 232 will similarly include refiner bars 236, refiner grooves 238, and teeth 400. Additionally, although not discussed in detail herein, the structure of the refining surfaces 44, 54 of the third and fourth refining bodies 42, 52, respectively, of FIG. 1 may be similarly configured as described herein. The refining surfaces 224, 234 of the first and second refining bodies 222, 232, respectively, may include substantially similar structures such that the refining surfaces 224, 234 of the first and second refining bodies 222, 232, respectively, are substantially similar in structure to the refining surfaces 224, 234 of the first and second refining bodies 222, 232, respectively.

[0095] 15 and 16 are detailed views of portions of one of the first and second refining surfaces 224, 234 of FIGS. 13 and 14, respectively. Figure 17 is a partial cross-sectional view of the first refiner bar 226 and teeth 400B and the second refiner bar 236 and teeth 400A, 400C, where the first refiner bar 226 and teeth 400B can be positioned on the first refining body portion 222 of Figures 13 and 15, and the second refiner bar 236 and teeth 400A, 400C can be positioned on the second refining body portion 232 of Figures 14 and 16, where the first refining body portion 222 is spaced apart from the second refining body portion 232 and positioned adjacent to and directly opposite the second refining body portion 232, defining a refining space 260 therebetween. 15-17 , the first refining surface 224 includes first refiner bars 226 that are separated from one another by first refiner grooves 228, and the second refining surface 234 includes second refiner bars 236 that are separated from one another by second refiner grooves 238. One or both of the first and second refining surfaces 224, 234 can include dams 229, 239 that are disposed within at least a portion of the first and second refiner grooves 228, 238, as described herein. Each of the first and second refiner bars 226, 236 is positioned at a radially inward position P on the respective first and second refining surfaces 224, 234. 100 to a first radially outward position P 200 In some examples, the radially inward position P 100 The first and second refiner bars 226, 236 may include locations at or near their respective radially inward locations 223, 233 (see Figures 13 and 14). The first and second refiner bars 226, 236 have a width W of about 2.0 mm to about 8.0 mm extending between the side edges of each refiner bar 226, 236. 226, W 236 This range includes all values ​​and subranges therebetween, including, for example, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, and 8.0 mm.

[0096] The first refining surface 224 includes first teeth 400B, which are positioned at the radially outer edge RO of the first refiner bar 226. 226 and the radially outer edge 227 of first refining body portion 222. First tooth 400B is positioned at a third radially outward position (e.g., P 400 ) and extends to a third radially outward position P 400 is the first radially outward position P of the first refining bar 226 200 The second refining surface 234 includes second teeth 400A, 400C that are positioned closer to the radially outer edge RO of the second refiner bar 236 than the outermost part (e.g., radially outer edge 227) of the first refining body 222. 236 and the radially outer edge 237 of the second refining body portion 232. The second teeth 400A, 400C are positioned at second or fourth radially outward positions (e.g., P 300 or P 500 ) and extending to second and fourth radially outward positions P 300 , P 500 is the first radially outward position P of the second refining bar 236 200 than the outermost part (e.g., radially outer edge 237) of second refining body portion 232.

[0097] With continued reference to FIGS. 15-17, the teeth 400A-400C may be arranged in concentric rings, extending substantially perpendicularly from their respective refining surfaces 224, 234 toward one another. The ring including the first teeth 400B is spaced apart from the radially outer edge RO of the first refiner bar 226 by the first substantially planar area 282. 226 The ring including second teeth 400A is spaced apart from the radially outer edge 227 of the second refiner bar 236 by a first substantially planar area 286 and is spaced apart from the radially outer edge 227 of the refining body 222 by a second substantially planar area 284. The ring including second teeth 400A is spaced apart from the radially outer edge 227 of the second refiner bar 236 by a first substantially planar area 286. 236 The first and second teeth 400A-400C are spaced apart from the first refining surface 224 of the first refining body 222 by a second substantially planar area 288 and are spaced apart from the ring containing the second teeth 400C by a second substantially planar area 288. In the embodiment shown in Figures 15-17, the first refining surface 224 of the first refining body 222 includes one concentric row / ring of first teeth 400B, and the second refining surface 234 of the second refining body 232 includes two concentric rows / rings of second teeth 400A, 400C, with the first and second teeth 400A-400C positioned on their respective refining surfaces 224, 234 such that the first teeth 400B mesh with the second teeth 400A, 400C. In other embodiments (not shown), first refining surface 224 can include two or more concentric rings of teeth, and second refining surface 234 can include one concentric row of teeth or three or more concentric rings of teeth. In all embodiments, one of the refining bodies will include one fewer ring of teeth than the other refining body, and the teeth are arranged on each refining body so that the teeth from one refining body intermesh with the teeth of the other refining body, as known in the art.

[0098] It is understood that the teeth 400A-400C can include any suitable shape and / or dimensions known in the art. As illustrated with respect to tooth 400A in FIG. 17 , in some examples, each of the first and second teeth 400A-400C can include a substantially pyramidal or trapezoidal shape, with a base 402, a radially inwardly facing surface 404, a radially outwardly facing surface 406, sides (not separately labeled) angled slightly inward toward a central axis (not labeled) of tooth 400A, and a generally planar outer surface 408. The radially inwardly and outwardly facing surfaces 404, 406 of each tooth 400A-400C can be sloped from the base 402 toward its respective outer surface 408. The outer surface 408 of each tooth 400A-400C can be substantially parallel to the plane of the respective substantially planar area 282, 284, 288 opposite the tooth 400A-400C. In other examples (not shown), each of the first and second teeth 400A-400C can include a regular shape, such as a substantially triangular shape, a rectangular shape, or any other suitable geometric shape. As shown in FIGS. 15-17, the bottom surface 402 of each tooth 400A-400C can include a radial dimension that is greater than the circumferential dimension, although in other embodiments (not shown), the bottom surface 402 can include a radial dimension that is less than the circumferential dimension. In some cases, at least a portion of the bottom surface 402 of the teeth 400A-400C can include a longitudinal length (not labeled) of at least 0.6 cm (i.e., radially), and in some particular cases, the longitudinal length can have a length between 0.6 cm and about 2 cm. In other cases, at least a portion of the bottom surface 402 of the teeth 400A-400C can include a width (not labeled) circumferentially, and the width can be between 0.6 cm and about 2 cm (e.g., the width of one refiner bar 226, 236). 226 , W 236 , and the width W of one adjacent groove 228, 238 G) is substantially equal to the combined width. G can be from about 2.0 mm to about 6.0 mm, including all values ​​and subranges therebetween, for example, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, and 6.0 mm. For example, bottom surfaces 402 of teeth 400A-400C may be circumferentially At least Also 1 In other cases, the bottom surfaces 402 of the teeth 400A-400C may have a circumferential 1 in 0.0mm ~2 0.0 mm (±0.5 mm). Additionally, one or more of the radially inwardly and outwardly facing surfaces 404, 406 or sides of one or more of the teeth 400A-400C may include one or more radially extending protrusions that may affect the interaction of the teeth 400A-400C with the wood fibers to separate the wood fiber bundles. The teeth 400A-400C may have a structure similar to that shown in U.S. Pat. No. 8,342,437 B2, the disclosure of which is incorporated herein by reference.

[0099] As shown in FIG. 17, the first refiner bar 226 is positioned on the floor F of the adjacent first refiner groove 228. 100 A first height H extending upward from 100 The second refiner bar 236 includes a floor F of the adjacent second refiner groove 238. 200 A second height H extending upward from 200 In some examples, the first and second heights H of the first and second refiner bars 226, 236 100 , H 200 can be substantially equal to each other, 、4 .0mm ~1The first and second refining body portions 222, 232 may have a first gap G of 0.0 mm (±0.5 mm), which range includes all values ​​and subranges therebetween, including, for example, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm. 100 and a first gap G 100 is the outer surface S of the first refiner bar 226 226 and the outer surface S of the second refiner bar 226 236 The second gap G 200 is defined between the generally planar outer surface 408 of the teeth 400A-400C and a respective one of the substantially planar areas 282, 284, 288 on the opposite side of the teeth 400A-400C, and G 200 is G 100 1. In some examples, the height (not labeled) of the teeth 400A-400C extending upward from the adjacent respective first or second refiner groove 228, 238 can be between about 8.0 mm and about 10.0 mm. This range includes all values ​​and subranges therebetween, including, for example, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10.0 mm. As shown in FIG. 17, the teeth 400A-400C are interdigitated such that a portion of one or both of the radially inwardly or outwardly facing surfaces 404, 406 of each tooth 400A-400C overlaps a portion of the radially inwardly or outwardly facing surface 404, 406 of the adjacent tooth 400A-400C in an axial direction, e.g., in the direction of the arrows in FIG. 1. The overlapping portions of the teeth 400A-400C form a third gap G. 300 and a third gap G 300 is defined between the radially inwardly or outwardly facing surfaces 404, 406 of each of the teeth 400A-400C. 300 is G 200In another example, G 300 is G 200 Less than or G 200 It is possible to have a larger value.

[0100] 1 and 17, when a wood pulp slurry is fed into the frame (e.g., inlet section 16) of refiner 10, the wood fibers are, for example, positioned approximately at a first radially inward position P 100 from approximately the first radially outward position P 200 The first gap G passes into a portion of the refining space 260 that is at least partially defined by the first and second refiner grooves 228, 238. The first and second refiner bars 226, 226 interact with each other as described herein to refine a significant number of wood fibers in the wood pulp. 100 for refining to occur 、0 It should be smaller than 0.9mm (±0.05mm), preferably 、0 .2mm ~0 It is considered that the distance should be within 0.9mm (±0.05mm). This range can be, for example, 0.2mm, 0.25mm, 0.3mm , 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, and 0.9 mm, including all values ​​and subranges therebetween. 100 teeth 、0 .1mm ~0 The refined wood fibers can be, for example, approximately at a first radially outward position P 200 Approximately the fourth radially outward position P 500into the portion of the refining space 260 defined at least in part by the respective first and second substantially planar areas 282, 284, 286, 288. To allow deflaking to occur, the second and third gaps G 200 and G 300 teeth 、0 .9mm ~1 It is contemplated that the average particle size should be within 0.5 mm (±0.05 mm). This range includes all values ​​and subranges therebetween, including, for example, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, and 1.5 mm. Teeth 400A-400C are adapted to break down or separate multiple wood fiber bundles in a wood pulp slurry, as described herein. G 200 is G 100 and is located radially outwardly at a first position P 200 At this point, refining stops and deflaking begins.

[0101] 1 and 15-17, the refining surfaces 224, 234 of the refining bodies 222, 232, and in particular the outer surfaces S of the first and second refiner bars 226, 236, 226 , S 226 , and outer surfaces 408 of teeth 400A-400C may wear and deteriorate over time. To compensate for this wear, the spacing between first and second refining members 20, 30, including first and second refining body portions 222, 232, respectively, may be readjusted as described herein to adjust first gap G 100 This adjustment of the first and second refining body portions 222, 232 reduces the second gap G when the refiner bars 226, 236 perform a more aggressive refining function and typically wear faster than the teeth 400A-400C. 200This difference in wear can be factored into the selection of teeth 400A-400C (e.g., the type of metal used for teeth 400A-400C, the second gap G, 200 The first and second substantially planar areas 282, 284, 286, 288 are each configured to define a second gap G sufficient to ensure that refining stops and deflaking begins when wood fibers enter the portion of the refining space 260 that is at least partially defined by the first and second substantially planar areas 282, 284, 286, 288. 200 When the refining bodies 222, 232 are new, the third gap G 300 is the second gap G 200 or a second gap G 200 As the refining surfaces 224, 234 wear and the refining members 20, 30 are moved closer together, the third gap G 300 is the second gap G 200 The third gap G 300 can be reduced.

[0102] In all embodiments described herein, refiner 10 of FIG. 1 may be coupled to a controller (not shown), which may be configured to monitor the performance of one or more fiber properties measured at one or more locations downstream of refiner 10, such as, for example, the number of fiber bundles, size, etc. (also referred to as "Wide Shives"), fibrillation, Canadian Standard Freeness, fiber length, fiber width, kink, curl, coarseness, number of fines, etc. The controller receives data from an AP Pulp Analyzer (Valmet Corp.). Based on this data, the controller can control the operation of the refiner 10 as part of a feedback loop. For example, the controller can adjust the spacing between one or more pairs of refining members 20, 30, 40, 50 to maintain one or more fiber properties within a predetermined target range. In some examples, the controller can also increase or decrease the rotational speed of one or more rotating rotor members (e.g., second and third refining members 30, 40) of the refiner 10 based on this data. In other examples, the controller can adjust the refining gaps G1, G2, G3, G4, G5, G6, G7, G8, G9, G10, G11, G12, G13, G14, G15, G16, G17, G18, G19, G20, G21, G22, G23, G24, G25, G26, G27, G28, G29, G30, G31, G32, G33, G34, G35, G36, G37, G38, G39, G40, G41, G42, G43, G44, G45, G46, G47, G48, G49, G50, G51, G52, G53, G54, G55, G56, G57, G58, G59, G60, G61, G62, G63, G64, G65, G66, G67, G68, G69, G70, G71, G72, G73, G74, G75, G76, G77, G78, G79, G80, G81, G82, G83, G84, G85, G86, G87, G88, G90, G91, G9 100 and deflaking gaps G2, G3, G4, G5, G6, G 200 , G 300 The operation of refiner 10 can be controlled, such as by varying the size of the fiber bundles, to produce refined softwood pulp having less than a predetermined number (e.g., 1,000 ppm) of fiber bundles of a particular size (e.g., about 150 to 2,000 microns wide and 0.3 mm to 40.0 mm long).

[0103] In other examples, refining elements 20, 30, 40, 50 according to the present disclosure may be installed in one or more of a plurality of refiners arranged in series, each of which may be substantially similar to refiner 10 of FIG. 1. A controller may control the operation of one or more of the plurality of refiners to maintain one or more fiber properties within predetermined target ranges. In some particular examples, refining elements 20, 30, 40, 50 according to the present disclosure may be installed only in the last refiner in the series, while in other examples, refining elements 20, 30, 40, 50 according to the present disclosure may be installed in two or more of the refiners.

[0104] Figure 18 is a flowchart illustrating an exemplary method for processing wood fibers. While reference is made to the components of refiner 10 in Figure 1, it is understood that the method is not limited to this configuration. The method can begin in step 500 by providing refiner 10 including at least a first pair of refining members 20 and 30, 40 and 50. The at least one pair of refining members can include first refining member 20 including a first refining body 22 including a first refining surface 24 and a second refining member 30 including a second refining body 32 including a second refining surface 34. The first refining surface 24 may include first refiner bars 26A separated by first refiner grooves 28A and second refiner bars 26B separated by second refiner grooves 28B, where the first refiner bars 26A have a first maximum height H1 extending upward from a floor F1 of the adjacent first refiner groove 28A, and the second refiner bars 26B have a second maximum height H2 extending upward from a floor F2 of the adjacent second refiner groove 28B. The second refining surface 34 may include second member refiner bars 36 separated by second member refiner grooves 38. The first refining member 20 may be spaced apart from the second refining member 30 to define a refining space 60 therebetween. At least a portion of the second member refiner bar 36 can be positioned directly opposite the second refiner bar 26B of the first refining member 20, so as to define gaps G2, G3, G4, G5, G6 between the portion of the second member refiner bar 36 and the second refiner bar 26B.

[0105] The method begins in step 510 by moving the first refining member 20 or the second refining member 30 relative to one another. At least one of the refining members 30 may be rotated, and in step 520, the method may continue to supply a slurry of wood pulp containing wood fibers to the refiner 10 so that the slurry passes through the refining space 60. In step 530, axial pressure may be supplied to at least one of the first refining member 20 or the second refining member 30 as the slurry is supplied such that gaps G2, G3, G4, G5, G6 between a portion of the second member refiner bar 36 and the second refiner bar 26B are between about 0.9 mm and about 1.5 mm, as described in detail herein, whereby at least a portion of the wood fiber bundles passing through the gaps G2, G3, G4, G5, G6 are separated, and the method may thereafter terminate.

[0106] FIG. 20 is a flowchart illustrating another exemplary method for processing wood fibers. While reference is made to components of refiner 10 in FIG. 1, it should be understood that the method is not limited to this configuration. For example, the refiner may include a cone-shaped refiner. The method may begin in step 600 by providing refiner 10 including at least a first pair of refining members 20 and 30, 40 and 50. The at least one pair of refining members may include first refining member 20 including a first refining body portion including a first refining surface. The first refining surface can include first refiner bars (e.g., refiner bars 26A, 26A', 1026A, 1026A' in Figures 6A, 6B, 19A, and 19B) separated by first refiner grooves, and second refiner bars (e.g., refiner bars 26B, 26B', 1026B, 1026B' in Figures 6A, 6B, 19A, and 19B) separated by second refiner grooves, where the first refiner bars have a first height extending upward from the floor of the adjacent first refiner groove and the second refiner bars have a second height extending upward from the floor of the adjacent second refiner groove. The at least one pair of refining elements can further include a second refining element 30 including a second refining body including a second refining surface. The second refining surface may include second member refiner bars, such as refiner bars 36, 36', 1036, 1036' in Figures 6A, 6B, 19A, and 19B, separated by second member refiner grooves. The first refining member 20 may be spaced apart from the second refining member 30 to define a refining space 60 therebetween. At least a portion of the second member refiner bar may be positioned directly opposite the second refiner bar of the first refining member to define a gap between the portion of the second member refiner bar and the second refiner bar.

[0107] The method may continue, in step 610, by rotating at least one of the first refining member 20 or the second refining member 30 so that the first and second refining members 20, 30 move relative to one another, and, in step 620, by supplying a slurry of wood pulp containing wood fibers to the refiner 10 so that the slurry passes through the refining space 60. In step 630, axial pressure may be applied to at least one of the first refining member 20 or the second refining member 30 as the slurry is supplied, separating at least a portion of the wood fiber bundles passing through the gap, whereupon the method may end. A gap defined between a portion of the second member refiner bar and the second refiner bar may increase in a direction extending from a first radially inward position toward a first radially outward position on the first refining surface along at least one section of the second refiner bar.

[0108] While particular embodiments of the present invention have been illustrated and described, various changes and modifications may be made. It should be understood that various changes, modifications, and variations can be made without departing from the spirit and scope of the present invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of the present invention.

Claims

1. 1. A refining element for a pulp refiner, the refining element comprising: a refining body including a refining surface; The refining surface comprises: first refiner bars separated by first refiner grooves and extending from a first radially inward position to a first radially outward position on the refining surface; second refiner bars separated by second refiner grooves and extending from a second radially inward position to a second radially outward position on the refining surface, the second radially outward position being closer to an outermost part of the refining body than the first radially outward position; the first refiner bar has a first height extending upwardly from the floor of the adjacent first refiner groove; the second refiner bar has a second height extending upward from a floor of an adjacent second refiner groove section, the second height being a minimum height of the second refiner bar and spaced apart from the second radially inward position, the second height being at least about 0.35 mm less than the first height; The refining member, wherein the first refiner bar is adapted to refine wood fibers and the second refiner bar is adapted to break down fiber bundles.

2. The refining member of claim 1 , wherein the minimum height of the second refiner bar is adjacent the second radially outward location.

3. The refining member of claim 1 , wherein the first height is substantially constant along the longitudinal length of the first refiner bar.

4. The refining member of claim 1 , wherein the first height is between about 4.0 mm and about 10.0 mm.

5. The refining member of claim 4 , wherein the second height is between about 0.35 mm and about 7.0 mm less than the first height.

6. The refining member of claim 4 , wherein the second height is between about 0.7 mm and about 7.0 mm less than the first height.

7. 2. The refining member of claim 1, wherein the second refiner bar is integral with the first refiner bar such that the second refiner bar extends from the first radially outward position to the second radially outward position.

8. 8. The refining member of claim 7, wherein each of the second refiner bars slopes downwardly substantially continuously along at least a portion of each second refiner bar extending between the first radially outward position and the second radially outward position.

9. The refining member of claim 1 , wherein at least a portion of the first refiner groove is equipped with a dam.

10. 2. The refining member of claim 1, wherein the first height of the first refiner bar includes a first maximum height, the second refiner bar includes a second maximum height extending upward from the floor of the adjacent second refiner groove portion, and a radially outer portion of each of the first refiner bars includes a step-down from the first maximum height to the second maximum height, and the second maximum height is at least about 1.5 mm less than the first maximum height.

11. third refiner bars separated by third refiner grooves, each extending to a third radially outward position on the refining surface; and fourth refiner bars separated by fourth refiner grooves, each of the fourth refiner bars extending to a fourth radially outward position on the refining surface that is closer to the outermost part of the refining body than the third radially outward position; the third refiner bar has a third height extending upward from the floor of the adjacent third refiner groove section, the fourth refiner bar has a fourth height extending upward from the floor of the adjacent fourth refiner groove section, the fourth height being a minimum height of the fourth refiner bar adjacent the fourth radially outward location, and the fourth height being at least about 0.35 mm less than the third height; The refining member of claim 1 , wherein the third refiner bar is adapted to refine wood fibers and the fourth refiner bar is adapted to break down fiber bundles.

12. 12. The refining member of claim 11, wherein the third refiner bar is integral with the second refiner bar such that the third refiner bar extends from the second radially outward position to the third radially outward position, and the fourth refiner bar is integral with the third refiner bar such that the fourth refiner bar extends from the third radially outward position to the fourth radially outward position.

13. 12. The refining member of claim 11, wherein the third height of the third refiner bar includes a third maximum height, the fourth refiner bar includes a fourth maximum height extending upward from the floor of the adjacent fourth refiner groove portion, and the radially outer portion of each of the third refiner bars includes a step-down from the third maximum height to the fourth maximum height, and the fourth maximum height is at least about 1.5 mm less than the third maximum height.

14. A pulp refiner, the pulp refiner comprising: The frame and and at least a first pair of refining members, said first pair of refining members comprising: a first refining member associated with the frame and including a first refining body including a first refining surface, the first refining surface comprising: first refiner bars separated by first refiner grooves and extending from a first radially inward position on the refining surface to a first radially outward position on the refining surface; and second refiner bars separated by second refiner grooves and extending from a second radially inward position on the refining surface to a second radially outward position on the refining surface, the second radially outward position being closer to an outermost part of the refining body than the first radially outward position. In the country, the first refiner bar has a first height extending upward from the floor of the adjacent first groove, the second refiner bar has a second height extending upward from the floor of the adjacent second groove, the second height being a minimum height of the second refiner bar and spaced apart from the second radially inward location, and the second height being at least about 0.35 mm less than the first height; a first refining member; and a second refining member associated with the frame and including a second refining body including a second refining surface including second member refiner bars separated by second member refiner grooves, the first refining member being spaced apart from the second refining member to define a refining space therebetween, and at least a portion of the second member refiner bar being positioned directly opposite the second member refiner bar to define a gap between the portion of the second member refiner bar and the second member refiner bar; a second refining member; The pulp refiner further comprises: a rotor associated with the frame and coupled to one of the first refining member or the second refining member such that rotation of the rotor effects movement of the one of the first or second refining members relative to the other refining member; A pulp refiner, wherein when a slurry of wood pulp containing wood fibers is supplied to the frame, the wood pulp slurry passes through the refining space so that a considerable number of the wood fibers in the wood pulp slurry are refined and multiple wood fiber bundles in the wood pulp slurry are separated.

15. 15. The pulp refiner of claim 14, wherein the minimum height of the second refiner bar is adjacent the second radially outward location.

16. 15. The pulp refiner of claim 14, wherein the first height is substantially constant along the longitudinal length of the first refiner bar.

17. 15. The pulp refiner of claim 14, wherein the second height is at least about 0.7 mm less than the first height.

18. 15. The pulp refiner of claim 14, wherein the first height of the first refiner bar includes a first maximum height, the second refiner bar includes a second maximum height extending upward from the floor of the adjacent second refiner groove portion, and the radially outer portion of each of the first refiner bars includes a step-down from the first maximum height to the second maximum height, and the second maximum height is at least about 1.5 mm less than the first maximum height.

19. The second member refiner bar comprises: a first refiner bar element extending from a first radially inward position to a first radially outward position on the second refining surface; a second refiner bar element that is closer to an outermost part of the second refining body than the first radially outward position and that extends to a second radially outward position on the second refining surface; The first refiner bar element has a first bar height extending upward from the floor of the adjacent groove, and the second refiner bar element has a second bar height extending upward from the floor of the adjacent groove, the second bar height being a height greater than the second refiner bar height.

15. The pulp refiner of claim 14, wherein the second bar height is at least about 0.35 mm less than the first bar height and is adjacent the second radially outward location.

20. 1. A method for treating wood fibers, the method comprising: Providing a refiner including at least a first pair of refining members, The first pair of refining members comprises: a first refining member including a first refining body including a first refining surface, the first refining surface including first refiner bars separated by first refiner grooves and having a first height extending upward from a floor of an adjacent first refiner groove, and second refiner bars separated by second refiner grooves and having a second height extending upward from a floor of an adjacent second refiner groove; a second refining member including a second refining body including a second refining surface, the second refining surface including second member refiner bars separated by second member refiner grooves, the first refining member spaced apart from the second refining member to define a refining space therebetween, and at least a portion of the second member refiner bar positioned directly opposite the second member refiner bar to define a gap between the portion of the second member refiner bar and the second member refiner bar; providing a refiner; rotating at least one of the first refining member or the second refining member such that the first and second refining members move relative to one another; supplying a slurry of wood pulp containing wood fibers to the refiner so that the slurry passes through the refining space; applying an axial pressure to at least one of the first refining member or the second refining member as the slurry is fed, the gap increasing in a direction extending from a first radially inward position to a first radially outward position on the first refining surface along at least one section of the second refiner bar; The method wherein at least a portion of the wood fiber bundles passing through the gap are separated.

21. 21. The method of claim 20, wherein the second height is a minimum height of the second refiner bar adjacent the first radially outward location, and the second height is at least about 0.35 mm less than the first height.

Images