KR20010106423A - Refiner plate with chicanes - Google Patents

Abstract

A refiner plate for the face of a refiner disc comprising a plurality of refiner segments (10) arranged side-by-side on the face of the disc to form a substantially annular refining region. Each refiner segment has a plurality bars (32, 34), chicanes (46) and grooves (36, 38) for refining a lignocellulosic material and forming a zig-zag path for receiving and transmitting steam generated during the refining process. The chicanes define a series of substantially arcuate lines (56) extending from a position intermediate the junction of the inlet and refining zones to the outer edge of the refiner plate in the counter-rotation direction.

Description

Purifier plate with chicane {REFINER PLATE WITH CHICANES}

In a highly consistent mechanical pulp refiner, wood fibers are worked between two relatively rotating discs, on which a refiner plate is mounted. The plate generally has radial bars and grooves. As a result of this purification operation a large volume of steam is produced between the plates. For effective purification, the fibrous material must remain on the bar surface between the plates, despite the high velocity of the flowing vapor, and the very high centrifugal force. Typically, steam is discharged through the grooves, and dams are provided in the grooves to block the flow of material and thus improve the retention time of the material in the refining zone.

In typical refiner plates with radial bars and grooves, the bars provide shock or pressure pulses that separate the fibers and break them down into fine fibers. The grooves allow for radially induced transport and vapor extraction of the fibers. Near the periphery of the plate, two factors, large radial vapor flow and large centrifugal force, act to blow the fiber too early outwards between the plates, thus reducing the purification effect. The flow restriction due to the small gap between the opposing plate and the fiber full groove leads to a vapor pressure peak between the plates, located radially inward from the periphery. These pressure peaks are a major source of refinery thrust loads and can cause control instability at high motor loads. Thus, the steam generated during purification is withdrawn from the purification zone as quickly as possible, while the pulp is preferably kept in the purification zone as long as possible.

The present invention relates generally to disk refiners for wood fiber materials. In particular, the present invention relates to purifier plate segments for such devices.

1 is a front view of a purifier plate segment according to the present invention;

2 is an enlarged cross sectional view along line 2-2 of FIG. 1;

3 is an enlarged front view of part 3 of FIG. 1;

4 is a partial cutaway front view of a purifier plate comprising a plurality of purifier plate segments in accordance with the present invention;

5 is a front view of an alternative embodiment of the purifier plate segment of FIG. 1; And

FIG. 6 is an enlarged front view of part 6 of FIG. 5;

In short, the present invention includes a purifier plate consisting of a plurality of purifier plate segments, each segment being formed in a pattern comprising a purifying zone having a plurality of bar segments disposed radially. Each of the bar segments has radially inner and outer ends disposed oppositely. The chicane extends obliquely from the outer end of the inner bar segment to the inner end of the outer bar segment to form a zig-zag shaped rib. Adjacent ribs form a plurality of grooves in a zig-zag shape that alternate with the ribs. The chicane forms at least one substantially arcuate line extending radially and laterally across at least the purification zone.

It is an object of the present invention to provide a purifier plate for the face of the purifier disc, which facilitates the removal of steam while maintaining the pulp in the purifier region to achieve satisfactory pulp quality.

This object is achieved by providing, in a preferred form, a cine to form a zig-zag flow path for most of the steam generated during the purification operation. The inclined leading side on each chicane induces the flow of wood fiber material into the gap between the purifier plates for grinding on the grinding surface of the bar. Although upwelling of the wood fiber material into the tablet gap limits the flow of vapor through the gap near the chicane, the chicane is positioned to form an arcuate line extending to the peripheral edge of the disk. Thus, vapor can flow in the gap to the edge of the disc through an arcuate passageway formed between the lines of chicane.

Thus, the purpose of achieving good fiber quality with good steaming treatment is to provide a chicane to guide the fiber in contact with the grinding surface while providing a plurality of flow paths for directing steam through the purification gap to the peripheral edge of the disc. Is achieved. As far as the inventors are aware, no one has previously provided a chicane that is arranged in a way that facilitates vapor flow within the purification gap.

Other objects and advantages of the present invention will become apparent from the drawings and the specification.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood and numerous objects and advantages will become apparent to those skilled in the art by reference to the accompanying drawings.

Referring to the drawings, wherein like reference numerals refer to like elements throughout the several views, the purifier plate according to the present invention is provided with a plurality of purifier plate segments 10 that can be fastened to the front face 12 of a substantially circular purifier disk 14. (See FIG. 2). Although in the illustrated embodiment each segment 10 has two zones 16 and 18 and each zone has a series of patterns oriented differently, each segment 10 has one zone or each It may optionally have three or more zones having a series of patterns of (see FIG. 1).

The plate segment 10 is attached to the disk face 12 in any convenient or conventional manner, for example by bolts (not shown) passing through the bore 20. One end of the bolt engages the disk 14 and the other end has a head structure that is supported in contact with the countersunk surface. The disk 14, which is shown only in part, has a central portion, with the disk rotating around the central portion and having a substantially circular outer circumference. Purifier plate segment 10 is arranged side by side on face 12 of disk 14 to form a substantially annular purifier face, generally indicated by reference numeral 22 (see FIG. 2). When faced with another purifier plate (not shown) held by another disk, the face 22 forms part of the purifier region.

Referring to FIG. 1, each refiner plate segment 10 has an inner edge 24 near the center of the disc, an outer edge 26 near the outer periphery of the disc, and trailing of adjacent refiner plate segments 10 ′. ) And leading and trailing side edges 28, 30 abutting leading side edges 30, 28, respectively (see FIG. 4). Although the following description will refer to one plate segment 10, it should be understood that all segments forming the annular plate are preferably substantially the same. Bars 32 and 34 and grooves 36 and 38 extend substantially radially, ie radially or parallel to the radius of the disk, or at an oblique angle to this radius. The plate segment 10 has at least one, and preferably two or three, separate pattern bars and grooves between the bars on the face, whereby the material to be purified is plate segments 10, 10 ′. May flow in the groove in a general direction from the inner edge 24 to the outer edge 26.

The first or inlet zone 16 has a plurality of bars 34 and grooves 38 between the adjacent bars 34, all of which extend substantially radially. This pattern is particularly suitable for receiving wood chips, wood pulp and the like and performing initial refining operations on the pattern to reduce the size of the material and flow radially outward to the second or refining zone 18. Purification zone 18 has a plurality of bars 32 and grooves 36 between adjacent bars 32, which also extend in parallel and substantially radially. A third zone or outer zone (not shown) may be provided between the outer edge 26 of the plate and the refining zone 18. As shown in FIG. 1, each zone 16, 18 may consist of a plurality of fields, each field having a uniform pattern. In the embodiment shown in FIG. 1, the segment has two fields in each zone. The pattern promotes the flow of vapor radially outward to the outer edge 26 of the disk 14 and radially inward to the inner edge 24 of the disk 14 for evacuation while retarding the flow of material. Ensure that the material is fully purified.

As the disk 14 and plate rotate, as a result of the centrifugal force, the partially purified material is directed radially outward. A significant amount of steam is also generated in the refining zone 18 which produces a large radial velocity steam flow. In particular, for relatively large discs, the centrifugal forces acting on the vapor and the chips to be partially refined increase dramatically as the material moves further radially outward. Although it is very desirable for the steam to be expelled from the refining zone quickly, essentially the partially refined fibers are not discharged quickly along the steam. This condition is affected by the radial pressure profile along the disk face 22 due to the vapor generated by the refinement at high consistency. Since the pressure peak is between the inner and outer edges 24 and 26 of the plate, the steam is directed forward (radially outward) and from the inside of the pressure peak back (radially out) from the outside of the pressure peak, against material transfer. Inside).

In a first embodiment of the invention, the purification zone 18 of the refiner plate segment 10 comprises a plurality of first rib segments 40 extending radially. Referring to FIG. 3, each first rib segment 40 is connected at a radial outer end 42 to a radially inner end 44 of the next outer first rib segment 40 ′ by a chicane 46. do. Each cine 46 is a second rib segment that extends obliquely in the disc rotation direction 48 from the inner first rib segment 40 to the outer first rib segment to form a radially extending jig-zag bar 32. It includes. Referring to FIG. 2, the inner side 50 of each chicane 46 is inclined from the top 52 of the chicane 46 toward the adjacent chicane 46 ′ to form a ramp face 54. do.

Grooves 36 formed between adjacent ribs 32 form a zig-zag path substantially across the refining zone 18 for the movement of the fibers. Wood fiber material moving in the grooves 36 is attracted by the centrifugal force to the corner of the chicane 46 and onto the ramp face 54 of the chicane 46. Therefore, the fibrillar material is led to the spaces or gaps between the opposing purifier plates for further grinding. Therefore, the zig-zag path retards the motion of the wood fiber material and prevents the material from leaving the purifier without being sufficiently refined. Most of the steam, which is less affected by the centrifugal force, continues to move in the groove 36 to the periphery of the plate through which the steam exits.

Referring to FIG. 1, chicane 46 forms a series of substantially arcuate lines 56. In the embodiment shown in FIG. 1, the radially innermost end 58 of the line 56 is located between the outer edge 26 of the plate and the connection of the inlet and refining zones 16, 18 with an arc segment ( 60). Each of the lines 56 extends from the arc segment 60 in the direction opposite to the direction of rotation 48 of the disk to the outer edge 26 of the plate, so that the arc formed by the line of chicane 46 is the point P. From the substantially uniform radius. The chicane 46 of the present invention causes the uptake of the conveying material to compress the plate gap near the chicane 46. However, the steam generated during the purification operation can flow radially through the passage 82 between the lines 56, 56 ′ of the chicane 46. Alternatively, the innermost end of the line of chicane 46 may be located at the connection of the inlet and purification zones 16, 18 and the line may not extend to the outer edge 26.

In the embodiment shown in FIGS. 5 and 6, the interrupted bar 84 may be disposed in the middle of a pair of zig-zag bars 86, 88. The interrupted bar 84 is formed by providing a gap 90 between the radially outer end 92 of the inner rib segment 94 and the radially inner end 96 of the outer rib segment 98. The gap 90 is disposed in the middle of the chicane 100 of the zig-zag bar pairs 86, 88 and therefore extends obliquely in the direction of disk rotation 48.

Referring to FIG. 4, the radially outer end 62 of each line 56 of chicane 46 ending on the trailing side edge 28 of the refiner plate segment 10 is defined by the adjacent purifier plate segment 10 ′. It is located adjacent the radially inner end 63 of the line 56 of the cine 46 on the leading side edge 28. Thus, the line of chicane 56 may extend across two purifier plate segments 10, 10 ′ to provide a continuous line from the arc segment to the outer edge 26 of the plate.

While the preferred embodiments have been shown and described, various modifications and substitutions may be made without departing from the spirit and scope of the invention. For example, the present invention may be advantageous to have three zones. Accordingly, it should be understood that the present invention has been described by way of example and not limitation.

Claims (16)

Radial inner and outer ends; A plurality of rib segments having radially inner and outer ends disposed opposite and substantially radially disposed; A plurality of cine extending obliquely from the radially outer end of the inner rib segment to the radially inner end of the outer rib segment to form a jig-zag shaped bar; A plurality of zigzag-shaped grooves disposed in the middle adjacent the bar; Consists of a refining zone having And the chicane forms at least one substantially arcuate line extending radially and laterally across at least a portion of the refining zone. 2. The refiner segment of claim 1, wherein the segment is rotatable in the direction of rotation and the chicane extends in the direction of rotation. 3. The refiner segment of claim 2, wherein the line extends in a direction opposite the direction of rotation. 2. The refiner segment of claim 1, wherein each of the chicanes comprises a top surface and a leading side, wherein the leading side is inclined from the top surface toward the adjacent chicane to form a ramp surface. 2. The refiner segment of claim 1, wherein the chicane defines a plurality of substantially arcuate lines extending radially and laterally across the segment. 2. The refiner segment of claim 1, wherein said line of chicanes extends from a point intermediate said inner and outer ends of said purifying zone to said outer end of said purifying zone. The method of claim 1, wherein the refining zone defines a plurality of gaps extending obliquely from the radially outer end of the inner rib segment to the radially inner end of the outer rib segment to form at least one interrupted bar. A purifier segment, characterized in that disposed in the middle of a pair of zigzag-shaped bars. Having opposed disks that rotate relatively, each of which has an outer edge, a refining zone, and retains a plate formed by a plurality of plate segments for purifying wood fiber material, each plate segment being substantially radial A plurality of rib segments disposed, each rib segment having opposing radially inner and outer ends, a plurality of scavengers, each of the scavenges being separated from the radially outer ends of the inner rib segments of the outer rib segment; Extending obliquely to the radially inner end to form a zig-zag bar and a plurality of zig-zag shaped grooves alternating with the bar, wherein the chicane is substantially arcuately extending radially and laterally across the refining zone. Forming a plurality of lines Purifier characterized in that. 10. The purifier of claim 8, wherein at least one of the disks is rotatable in a rotational direction and the chicane extends in the rotational direction. 10. The refiner segment of claim 9, wherein the line extends in a direction opposite the direction of rotation. 12. The apparatus of claim 10, wherein the plurality of plate segments comprises first and second plate segments, each of the plate segments having a leading edge and a trailing edge, wherein the trailing edge of the first plate segment is the first plate segment. Adjacent to the leading edge of a two plate segment, at least one of the lines having a first portion having an outer end ending at the trailing edge of the first plate segment and starting at the leading edge of the second plate segment And a second portion having an inner end. 12. The purifier of claim 11, wherein said outer end of said first portion is disposed adjacent said inner end of said second portion to form a continuous line. 9. The disk of claim 8, wherein the disk further comprises a radially inner inlet zone for receiving wood fiber material and a radially outer purification zone for purifying wood fiber material, wherein the rib segment and the scaine are disposed in the purification zone. Purifier characterized in that the. 14. The purifier of claim 13, wherein each of said lines has a radially inner end positioned midway between said edge of said disk and said inlet zone, each of said lines extending to said edge of said disk. 10. The purifier of claim 8, wherein said opposed disk defines a purification gap and said line of chicanes defines a plurality of flow passages in said purification gap. During the purification of the wood fiber material in the refiner, a flow of transfer material and steam occurs between a pair of relatively rotating opposed tablet discs forming a tablet gap, each of which has a radial inner and outer edge, And a surface pattern comprising a refining zone having a plurality of rib segments disposed radially, each rib segment having a plurality of radial inner and outer ends, a plurality of chicanes, each of which has a portion of the inner rib segment. Extending obliquely from the radially outer end to the radially inner end of the outer rib segment to form a jig-zag shaped bar with an upper grinding surface, the chicane having an inclined leading surface, radially across the refining zone to the edge of the disc and A plurality of substantially arcuate, extending laterally Forming lines and alternating zigzag-shaped grooves with bars, 1) directing the conveying material over the inclined leading surface of the chicane into the tablet gap with centrifugal force generated by rotating the at least one tablet disk for grinding on the grinding surface of the bar; 2) directing the first portion of steam through the groove to the outer edge of the disk by centrifugal force thereby removing the first portion of steam from between the disk; 3) directing a second portion of the vapor through the intermediate purification gap adjacent the line of chicane by centrifugal force thereby removing the second portion of the vapor from between the discs; Method comprising a.