Pulper and pulper rotor

Abstract

The invention relates to a pulper rotor arranged close to a pulper screen (100), the pulper rotor comprising: a number of blades; and a perforated plate (200) spanning at least a part of the blades, wherein the perforated plate holes run through from a side of the perforated plate (200) facing away from the pulper screen (100) to a side facing towards the pulper screen (100). The invention also relates to a pulper having a pulper rotor as described above.

Description

TECHNICAL FIELD

[0001] The present invention relates to a pulper rotor, in particular for a pulper of a pulp preparation system of a papermaking line. The present invention also relates to a pulper. BACKGROUND

[0002] The existing pulper rotor is generally composed of pulping function blades and cleaning function blades, or blades with both cleaning and pulping functions, and the blades are bare and exposed to the screen plate. In this way, there is a situation that large pulp pieces directly pass through the screen plate. This results in that the pulp after pulping contains some pulp pieces, which affects the quality of the subsequent products. In order to improve the quality of the pulp (as low as possible pulp piece content), the current method is to either increase the pulping time or to reduce the aperture of the screen plate. Increasing the pulping time means larger tank and larger installed power, which leads to higher operating costs. At the same time, since the pulp flow rate is limited by the aperture of the screen plate, the aperture of the screen plate cannot be too small.

[0003] Therefore, it is desirable to provide a pulper rotor, so that at least most of the pulp cannot directly pass through the screen holes of the pulper rotor screen plate without being affected by the blades, but without significantly increasing the pulping time or reducing the aperture of the screen plate. SUMMARY

[0004] To this end, the present invention provides a pulper rotor arranged close to a pulper screen plate, comprising: a plurality of blades; and a hole plate spanning at least a portion of the blades, wherein the holes of the hole plate pass through from a side of the hole plate facing away from the pulper screen plate to a side of the hole plate facing towards the pulper screen plate.

[0005] In this way, at the position where the hole plate spans between the blades, the pulp in the pulper will first pass through the hole plate before reaching the screen plate, then be slightly loosened in the narrow gap between the hole plate of the rotor and the screen plate, and finally pass through the screen plate. This greatly improves the quality of the good pulp passing through the screen plate.

[0006] Preferably, the hole plate spans all the blades of the pulper rotor, thereby forming a complete or internally hollow annular closed area in the entire area of the pulper rotor.

[0007] The hole plate can close the entire area between the blades it spans, so that the pulp flowing into the area between the two blades can only pass through the hole plate. Alternatively or additionally, the hole plate can also only close part of the area between the blades it spans, so that part of the pulp in the pulper can directly pass through the gap between the hole plate and the blade to reach the screen plate, and the other part of the pulp can first pass through the hole plate and then pass through the narrow gap between the hole plate and the screen plate, thereby improving the defibration effect on the pulp. For the latter case, the gap between the hole plate and the blade can be located radially inward of the pulper rotor or can be arranged in the middle in the radial direction of the pulper rotor.

[0008] According to a preferred embodiment of the pulper rotor of the present application, the hole plate has a plurality of radially extending grooves on the side facing the screen plate of the pulper. These grooves constrain the pulp that has passed through the hole plate of the pulper rotor to generate a certain degree of radial flow, thereby additionally playing a certain defibration effect.

[0009] According to a preferred embodiment of the pulper rotor of the present application, the holes of the hole plate can be distributed throughout the entire area of the hole plate, or only in part of the area. In the areas of the hole plate where there are no holes, the grooves on the side of the hole plate facing the screen plate of the pulper can play a major defibration effect in these areas. Optionally, the grooves on the side of the hole plate facing the screen plate of the pulper have the same or different radial extension angles relative to the radial direction of the pulper rotor, and each groove can also have the same or different radial extension angles relative to each other. It is also optional that the grooves on the side of the hole plate facing the screen plate of the pulper have an angle that is tilted forward or backward relative to the direction of rotation of the pulper rotor, in order to further adapt to the purpose of improving the defibration effect.

[0010] It should be understood that the hole plate has a linear, polyline or arc-shaped shape on the radially outer edge. As long as the hole plate forms a gap between the screen plate in an overall plate structure, and the pulp can pass through the holes or other structures such as gaps to reach the gap, the gap can have the effect of improving the defibration effect. Obviously, for the arc-shaped edge of the hole plate, it can be optionally designed as a circular arc shape, or any curve that is recessed radially inward or protrudes radially outward relative to the circular arc shape.

[0011] Preferably, the holes of the hole plate have regular or irregular cross-sectional shapes. The holes of the hole plate can have circular or square cross-sectional shapes. The holes of the hole plate can have axes that are parallel or inclined relative to the axis of the pulper rotor. The hole plate can have holes of uniform or non-uniform sizes.

[0012] According to another aspect of the present application, a pulper having the above-mentioned pulper rotor is also provided. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 schematically shows a top view of a pulper screen plate;

[0014] Figure 2 schematically shows a top view of a pulper rotor of the present application;

[0015] Figure 3 schematically shows a top view of a pulper rotor of the present application assembled with a pulper screen plate;

[0016] Figure 4 schematically shows an axial cross-sectional view of a pulper rotor of the present application assembled with a pulper screen plate. DETAILED DESCRIPTION

[0017] The present application will be described in detail below with reference to the accompanying drawings, it is to be noted that the specific embodiments should not be construed as limiting the present application.

[0018] Figure 1 schematically shows a top view of a pulper screen plate 100. As shown, the screen plate 100 has a plurality of screen holes 110 thereon, which are adapted to screen out good pulp from the pulper. It should be understood that the circular shape profile of the screen plate 100 and the distribution of the screen holes 110 thereon are schematic and not limiting to the present application.

[0019] Figure 2 schematically shows a top view of a pulper rotor of the present application. The perforated plate 200 is bridged between the blades 220 of the pulper rotor, and pulp can pass through the holes 210 of the perforated plate 200 to reach the bottom of the pulper rotor.

[0020] Figure 3 and Figure 4 schematically shows a top view and an axial cross-sectional view, respectively, of a pulper rotor of the present application assembled with a pulper screen plate 100. The perforated plate 200 of the pulper rotor has a gap with the screen plate 100. Pulp passes through the gap to enter the screen holes 110 of the screen plate 100, so that good pulp is screened out from the screen holes 110. The gap advantageously improves the effect of defiberation of the pulp. From the top view, the hole size of the perforated plate 200 of the pulper rotor is larger than the hole size of the screen holes 110 of the screen plate 100, which makes the perforated plate 200 of the pulper rotor substantially not function as a screen, but enables a large amount of pulp to pass through to reach the gap between the bottom of the perforated plate and the surface of the screen plate 100. Figure 3 and Figure 4 From the top view, the hole size of the perforated plate 200 of the pulper rotor is larger than the hole size of the screen holes 110 of the screen plate 100, which makes the perforated plate 200 of the pulper rotor substantially not function as a screen, but enables a large amount of pulp to pass through to reach the gap between the bottom of the perforated plate and the surface of the screen plate 100.

[0021] The preferred embodiments of the present application have been described above, but the spirit and scope of the present application are not limited to the specific ones disclosed herein. Those skilled in the art can make more embodiments and applications according to the teachings of the present application, which are all within the spirit and scope of the present application. The spirit and scope of the present application are not defined by the specific embodiments, but by the claims.

[0022] List of reference numerals

[0023] 100 screen plate

[0024] 110 screen hole

[0025] 200 aperture plate

[0026] 210 aperture of aperture plate

[0027] 220 blade

Claims

1. A pulper rotor, which is arranged close to a pulper screen (100), characterized in that, The pulper rotor comprises: a plurality of blades; and a perforated plate (200) spanning at least a portion of the blades, wherein the perforated plate has perforations (210) extending from a side of the perforated plate facing away from a pulper screen (100) to a side of the perforated plate facing towards the pulper screen (100).

2. The pulper rotor of claim 1, wherein, The perforated plate (200) spans all blades of the pulper rotor.

3. The pulper rotor of claim 2, wherein, The perforated plate (200) closes the entire or partial area between the spanned blades.

4. The pulper rotor of claim 3, wherein, The perforations (210) of the perforated plate (200) are distributed over the entire or partial area of the perforated plate (200).

5. The pulper rotor of claim 4, wherein, The radially outer edge of the perforated plate (200) has a linear, polygonal or arcuate shape.

6. The pulper rotor of claim 4, wherein, The perforated plate (200) has a plurality of radially extending grooves on the side facing towards the pulper screen (100).

7. The pulper rotor of claim 6, wherein, The grooves on the side of the perforated plate (200) facing towards the pulper screen (100) have the same or different radial extension angles relative to the radial direction of the pulper rotor.

8. The pulper rotor of claim 6, wherein, The grooves on the side of the perforated plate (200) facing towards the pulper screen (100) have an angle of inclination forward or backward relative to the direction of rotation of the pulper rotor.

9. A pulper rotor according to claim 7 or 8, characterized in that The perforations (210) of the perforated plate (200) have regular or irregular cross-sectional shapes.

10. The pulper rotor of claim 9, wherein, The perforations (210) of the perforated plate (200) have circular or square cross-sectional shapes.

11. The pulper rotor of claim 9, wherein, The perforations (210) of the perforated plate (200) have axes that are parallel or inclined relative to the axis of the pulper rotor.

12. The pulper rotor of claim 7 or 8, wherein, The perforated plate (200) has a uniform or non-uniform size of the perforation diameter.

13. A pulper characterized in that The pulper has a pulper rotor according to any one of claims 1 to 12.

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