Hydrocyclone with Improved Fluid Injection Member

Abstract

A hydrocyclone having a middle part with a longitudinal axis and a radius, and a fluid injection member releasably connected to the middle part. The fluid injection member has a dilution channel passing therethrough and two spaced-apart dilution ports, at least one of the dilution ports being at an angle between 15 and 75 degrees relative to the middle part radius. The injection member includes a nozzle housing releasably connected to the middle part, the nozzle housing having a dilution channel passing therethrough, and a nozzle adapted to be connected to the nozzle housing, the nozzle being planar and having at least one dilution port passing therethrough, the nozzle being receivable within the dilution channel.

Description

BACKGROUND OF THE INVENTION

[0001] The present disclosure relates to a hydrocyclone for separating a fibrous pulp suspension containing relatively heavy contaminants.

[0002] Hydrocyclones are used in the pulp and paper industry to clean contaminants from fibrous pulp suspensions, particularly but not limited to, contaminants that differ in density from the fibers. SUMMARY OF THE INVENTION

[0003] Disclosed is a hydrocyclone having a middle portion with a longitudinal axis and a radius, and a fluid injection member having at least one dilution port therethrough, the dilution port allowing fluid to enter with both a tangential velocity component and a radial velocity component.

[0004] In one embodiment, the hydrocyclone has a middle portion with a longitudinal axis and a radius, and a fluid injection member releasably connected to the middle portion. The fluid injection member has a dilution channel therethrough and at least one spaced dilution port, the at least one dilution port being at an angle between 5 and 75 degrees relative to the middle portion radius. The injection member includes a nozzle housing releasably connected to the middle portion, the nozzle housing having a dilution channel therethrough, and a nozzle adapted to be connected to the nozzle housing, the nozzle being planar and having at least one dilution port therethrough, the nozzle being receivable within the dilution channel.

[0005] In one embodiment, one dilution port injects fluid into the middle portion in one direction, while another dilution port injects fluid into the middle portion in a different direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 is a schematic cross-sectional view of an embodiment of a hydrocyclone according to U.S. Patent 7,404,492 to Kucher et al., issued Jul. 29, 2008.

[0007] Figure 2 is an exploded side perspective view of an improved fluid injection member including a nozzle releasably connected to a nozzle housing, the nozzle housing being releasably connected to the middle portion of the hydrocyclone.

[0008] Figure 3 is a side perspective view of the improved fluid injection member attached to the middle portion of the hydrocyclone.

[0009] Figure 4 is a cross-sectional view of the improved fluid injection member attached to the middle portion of the hydrocyclone.

[0010] Figure 5 is a side view of the fluid injection member in a position attached to the middle portion.

[0011] Figure 6It is a left perspective view of a fluid injection member.

[0012] Figure 7 It is a right perspective view of a fluid injection member.

[0013] Figure 8 It is similar to Figure 3 a view showing only the removal of the nozzle housing.

[0014] Figure 9 It is similar to Figure 5 a view showing only the removal of the nozzle housing, showing the orientation of the nozzle dilution port relative to the middle portion.

[0015] Figure 10 It is a rear view of the nozzle of a fluid injection member having two spaced-apart dilution ports extending in the same direction.

[0016] Figure 11 It is Figure 10 a side view of the nozzle.

[0017] Figure 12 It is Figure 10 a front view of the nozzle.

[0018] Figure 12A It is a cross-sectional view of the nozzle taken along line A-A of Figure 12 and Figure 12 the nozzle.

[0019] Figure 12B It is a cross-sectional view of the nozzle taken along line B-B of Figure 12 and Figure 12 the nozzle.

[0020] Figure 12C It is a cross-sectional view of the nozzle taken along line C-C of Figure 12 and Figure 12 the nozzle.

[0021] Figure 13A It is a rear view of the nozzle of another embodiment, Figure 13B and it is a front view of the nozzle of another embodiment, which has two spaced-apart dilution ports, one port extending in one direction and the other port extending in the opposite but parallel direction.

[0022] Figure 14A It is a rear view of the nozzle of yet another embodiment, while Figure 14B it is a front view of the nozzle of yet another embodiment, which has two spaced-apart dilution ports, one port extending in one direction and the other port extending in the opposite direction at an angle relative to the port extending in one direction.

[0023] Figure 15is a cross-sectional view perpendicular to the longitudinal axis of the hydrocyclone and passing through the nozzle dilution port.

[0024] Figure 16 is a cross-sectional view of a portion of the hydrocyclone along the longitudinal axis of the hydrocyclone with the nozzle removed.

[0025] Before explaining in detail an embodiment of the present disclosure, it should be understood that the present disclosure is not limited in its application to the structural details and component arrangements set forth in the following description or shown in the drawings. The present disclosure is capable of other embodiments and of being practiced or carried out in various ways. Additionally, it should be understood that the phrases and terms used herein are for the purpose of description and should not be regarded as restrictive. As used herein, "comprising" and "including" and their variants are intended to cover the items listed thereafter and their equivalents as well as additional items. As used herein, "consisting of" and its variants are intended to cover only the items listed thereafter and their equivalents. Further, it should be understood that terms such as "forward," "backward," "left," "right," "upward," and "downward" are for convenience only and should not be construed as restrictive terms. Detailed Description

[0026] Conventional hydrocyclone

[0027] Referring to the drawings, like reference numerals denote the same or corresponding elements throughout the several views.

[0028] FIG. 1 shows a conventional hydrocyclone 1, which includes a housing 2 that forms an elongated generally conical separation chamber 3 having a bottom end 4 and a top end 5. An inlet member 6 is provided on the housing 2 and is designed to tangentially supply a fiber suspension to be separated into the separation chamber 3 at its bottom end 4. At the top end 5 of the separation chamber 3, there is a reject fraction outlet 7 for discharging the reject fraction produced in the suspension, and at the bottom end 4 of the separation chamber 3, there is a central accept fraction outlet 8, which is defined by a conventional vortex finder 9, for discharging the major portion of the produced suspension.

[0029] In operation, a pump 10 pumps a fiber suspension containing heavy contaminants through a conduit 77 to the inlet member 6, which tangentially supplies the suspension to the separation chamber 3. The entering suspension forms a vortex in which the heavy contaminants are radially pulled outward by centrifugal force while the fibers are radially pushed inward by drag force. Thus, a major portion of the suspension substantially containing fibers is produced at the center of the vortex, and a reject fraction containing heavy contaminants and some fibers is produced radially outward in the separation chamber. The produced reject fraction is discharged through the reject fraction outlet 7, and the produced major portion is discharged through the central accept fraction outlet 8.

[0030] The housing 2 forms a first elongated generally conical chamber portion 3a of the separation chamber 3, extending from the bottom end 4 of the separation chamber 3 to the top end 12 of the first chamber portion 3a having an axial opening 13, and forms a second elongated generally conical chamber intermediate portion 3b of the separation chamber 3, extending from its bottom end 14 to the top end 5 of the separation chamber 3. The axial opening 13 at the top end 12 of the first chamber portion 3a also forms an opening leading to the second chamber portion 3b at its bottom end 14. The first chamber portion 3a and the second chamber portion 3b are aligned with each other such that their central symmetry axes form a common central symmetry axis 15. The eddy current formed in the separation chamber 3 during operation extends from the first chamber portion 3a through the axial opening 13 at the top end 12 of the first chamber portion 3a to the second chamber portion 3b.

[0031] The injection member 16 is provided on the housing 2 to tangentially inject a liquid into the separation chamber 3 at a certain distance from the top end 5 of the separation chamber 3, and this distance is at least 40% of the length of the separation chamber 3. In the embodiment of FIG. 1, the second chamber portion 3b includes an injection channel 3c at the bottom end 14 of the second chamber portion 3b for receiving the liquid injected by the injection member 16. The injected fluid volume is preferably equal to about 10% to 20% of the fluid at the inlet of the hydrocyclone, about 15% in the illustrated embodiment.

[0032] The fluid injection member can inject a liquid or a mixture of liquid and gas. The advantage of injecting a mixture of liquid and gas is that the gas mechanically dissolves the fiber web generated in the second chamber portion. Advantageously, the injected fluid can be a fiber suspension having a fiber concentration lower than that of the fiber suspension supplied by the inlet member.

[0033] In operation, the pump 17 pumps a liquid through the conduit 18 to the injection member 16, and the injection member 16 tangentially injects the liquid into the second chamber portion 3b such that the injected liquid increases the rotational speed of a part of the eddy current in the chamber portion 3b, thereby increasing the separation efficiency with respect to the fibers present in the eddy current portion. As shown by the dashed line 79 in FIG. 1, a part of the flow of the fiber suspension conducted through the conduit 77 can, optionally, be guided to the conduit 18 via the adjustable valve 20.

[0034] In one embodiment, the length L1 of the first chamber portion 3a is about 60 cm, and the length L2 of the second chamber portion is about 50 cm. The width of the second chamber portion 3b measured at the liquid injection location is about 6 cm, and the width of the first chamber portion 3a at the suspension supply location is about 8 cm.

[0035] Typically, the length L1 of the first chamber portion 3a should be 5 to 9 times the width of the first chamber portion 3a measured at the point where the suspension is supplied to the first chamber portion. The width of the second chamber portion 3b measured at the point where the liquid is injected should be equal to or less than the width of the first chamber portion measured at the point where the suspension is supplied to the first chamber portion, and preferably should be 65 to 100% of the width of the first chamber portion. The width of the first chamber portion at the top should be 50% to 75% of the width of the first chamber portion measured at the point where the suspension is supplied to the first chamber portion.

[0036] Improved fluid injection member

[0037] As Figures 2 - 5 Shown is an improved hydrocyclone 26 having an improved intermediate portion 29 with a double-shell structure, the intermediate portion 29 having a longitudinal axis 15 and a radius. The hydrocyclone of the present embodiment 26 has most of the common elements with the prior art structure 1 shown in FIG. 1, except for the fluid injection member 16.

[0038] As Figures 2 - 12C Shown is an improved fluid injection member 28 for a Figures 2 - 5 hydrocyclone, the fluid injection member 28 being adapted to be releasably connected to the intermediate portion 29 of the hydrocyclone. The hydrocyclone intermediate portion 29 used herein refers to the part of the hydrocyclone 26 between the bottom end 4 and the top end 5 of the hydrocyclone. The improved hydrocyclone 26 also has a safety plug 33 extending through the outer housing 23 of the intermediate portion 29.

[0039] The intermediate portion 29 includes an outer housing 23 and an inner housing 25 spaced apart from the outer housing 23, as Figure 4 shown. The two housings act together to provide a strong structural component of the hydrocyclone 26. In addition, the two housings provide a safer hydrocyclone because if the inner housing may rupture, the outer housing provides an additional layer of safety. These two plates also allow the outer housing to be stronger, while the inner housing can be elastic, for example, having higher chemical resistance and wear resistance. The fluid injection member 28 is adapted to be releasably connected to the intermediate portion 29 and is used to connect the outer housing 23 and the inner housing 25 together. This firm connection between the outer housing and the inner housing allows the housings to be thinner than housings without such a connection. More specifically, the injection member 28 is adapted to be connected to the intermediate portion 29 in a double twist, bayonet, locking engagement manner. The bayonet connection is in the form of a flange 36 (see Figure 7 ) extending outwardly on the nozzle housing 38, which interlocks with a corresponding flange 39 in an opening 41 in the intermediate portion 29 (see Figure 8 ), and the nozzle housing 38 is twisted relative to the intermediate portion 29, causing the nozzle housing flange 36 to be fixed behind the intermediate portion flange 39, as Figure 4As shown. A variety of O-ring seals 42 help to ensure a fluid-tight connection.

[0040] More particularly, the nozzle housing 38 is positioned before engaging the upwardly extending nozzle housing 38 at the middle portion 29, as Figure 5 shown, and then the nozzle housing 38 is rotated to its downwardly extending position, as Figure 3 shown, in order to engage a bayonet connection. In the illustrated embodiment, the nozzle housing 38 has an elbow shape to allow the injection member 28 to be positioned closely against the middle portion 29, but in other embodiments (not shown), the nozzle housing 38 may extend along the radius or at other angles of the middle portion 29. In other embodiments (not shown), the nozzle housing 38 may extend in any desired direction once fixed to the middle portion.

[0041] In the illustrated embodiment, the fluid injection member 28 includes a nozzle housing 38 releasably connected to the middle portion 29, the nozzle housing having a dilution channel 43 therethrough, as Figure 4 shown, and a nozzle 40 adapted to be connected to the nozzle housing 38. The nozzle 40 is generally planar, as Figure 4 , Figure 11 and Figure 12A shown, but in other embodiments (not shown) may be convex, concave, or some other shape. In the illustrated embodiment, the nozzle 40 is positioned within the dilution channel 43 and an inner portion 45 of the nozzle 40 extends through an opening 41 in the middle portion 29. The nozzle 40 is fixed between the nozzle housing 30 and the middle portion 29 by a flange 47 that extends radially of the nozzle, as Figure 4 and Figure 11 shown. A tongue 49 in the middle portion opening 41 is aligned with a notch 51 on the nozzle 40, so that the orientation of the nozzle 40 relative to the nozzle housing 38 is fixed, as Figure 6 and Figure 7 shown. Although the nozzle 40 and the nozzle housing 38 are formed of two separate components, in other embodiments (not shown), the fluid injection member 28 may be formed as a single piece.

[0042] In one embodiment, the nozzle 40 has at least one dilution port 50 extending through the nozzle 40, the dilution port 50 being at an angle 27 (see Figure 15 ) between 5 and 75 degrees relative to the middle portion radius 37, and most preferably, at approximately 48 degrees, as Figure 15 shown. In other words, the fluid from the dilution port 50 enters the middle portion with both a tangential velocity and a radial velocity. In other less preferred embodiments (not shown), the dilution port may direct along the middle portion radius 37 or only in the tangential direction. In the illustrated embodiment, the dilution port 50 is both angled relative to the middle portion radius and perpendicular to the middle portion longitudinal axis 15.

[0043] More particularly, in the illustrated embodiment, the injection member 28 has two spaced dilution ports 50 and 52 which pass through the injection member 28 in the form of angled openings 50 and 52 in the nozzle 40. In other embodiments (not shown), there may be a single dilution port passing through the nozzle 40. In the illustrated embodiment, the dilution ports 50 and 52 are cylindrical, but in other embodiments (not shown), other port shapes such as slots, squares, diamonds, etc. may be used. Further, in the illustrated embodiment, the opening area of each nozzle port is between 10 and 500 square millimeters, preferably between 10 and 300 square millimeters, and most preferably between 10 and 200 square millimeters. The opening area is the area of the port when passing through the port cross-section perpendicular to the longitudinal axis of the port. In a preferred embodiment, the total relative opening area of the nozzle ports divided by the cross-sectional area of the inner housing in which the nozzle ports are located is between 0.1% and 10%.

[0044] In the illustrated embodiment, the injection member 28 is located at least about 30% of the total length of the chamber upward from the top end 5, and preferably greater than 40% upward. In other embodiments (not shown), other locations may be used. The amount of injection fluid from the nozzle ports totals about 2% to 10% of the fluid at the hydrocyclone inlet, and preferably about 5% in the illustrated embodiment. Higher injection fluid amounts are possible with additional nozzle ports. In other embodiments (not shown), the hydrocyclone may include additional fluid injection members spaced around the periphery of the hydrocyclone or along the hydrocyclone axis 15.

[0045] The nozzle 40 is adapted to be attached to the nozzle housing 38 such that the injection directions of the dilution ports 50 and 52 are in a direction perpendicular to the longitudinal axis 15 of the hydrocyclone 26. This causes the injection fluid entering the middle portion 29 to be directed around the interior of the middle portion 29.

[0046] As Figure 13A and Figure 13B shown is another embodiment of a nozzle 40' having two spaced dilution ports 50' and 52', where one port 50' extends in one direction and the other port 52' extends in an opposite but parallel direction.

[0047] In yet another embodiment of the nozzle 40”, as Figure 14A and 14B shown, the dilution port 50” is at an angle of 15 to 75 degrees relative to the middle portion radius and not perpendicular to the middle portion longitudinal axis 15, while the other dilution nozzle port 52” is at an angle of 0 degrees (see Figure 16 line 33 in Figure 16The angle between the line 31) in. In this alternative embodiment, one dilution port 50" facilitates the circumferential movement of the fluid in the hydrocyclone, while the other dilution port 52" is angled towards the top 5 of the hydrocyclone and facilitates the downward movement of the fluid along the hydrocyclone. In other embodiments (not shown), two spaced-apart dilution ports may be oriented in other directions.

[0048] The improved fluid injection member 28 of the present disclosure provides greater flexibility to allow fluid to be injected into the hydrocyclone in different directions. The improved fluid injection member 28 having two spaced-apart dilution ports allows fluid to be injected into the hydrocyclone in multiple directions, and the two dilution ports help to ensure fluid injection in the event of a blockage of one port. The planar nozzle 40 allows the dilution port to be selected at the hydrocyclone according to the material separated in the hydrocyclone, thus allowing the injection member 28 to be more easily adjusted to meet the specific requirements of the hydrocyclone. The bayonet connection allows the fluid injection member 28 to be firmly and quickly connected to the intermediate portion 29.

[0049] Various other features and advantages of the present disclosure are apparent from the following claims.

Claims

1. A hydrocyclone having a middle part and a fluid injection member, the middle part having a longitudinal axis and a radius, the fluid injection member having at least one dilution port therethrough, the dilution port being angled relative to the middle part radius to cause fluid to enter with both a tangential velocity component and a radial velocity component.

2. The hydrocyclone according to claim 1, wherein The middle part includes two spaced-apart housings, and the fluid injection member is adapted to be connected to the two housings.

3. The hydrocyclone according to claim 1, wherein, The hydrocyclone has a top end, and wherein the at least one nozzle dilution port is angled towards the top end of the hydrocyclone.

4. The hydrocyclone according to claim 1, wherein, The fluid injection member is adapted to be releasably connected to the middle part.

5. A hydrocyclone having a middle part, a fluid injection member, and at least one dilution port therethrough, the middle part having a longitudinal axis and a radius, the fluid injection member being connected to the middle part, the fluid injection member having a dilution channel therethrough, the dilution port being angled between 5 and 75 degrees relative to the middle part radius to cause fluid to enter with both a tangential velocity component and a radial velocity component.

6. The hydrocyclone according to claim 5, wherein, The fluid injection member includes a nozzle housing connected to the middle part, and at least one nozzle adapted to be connected to the nozzle housing.

7. The hydrocyclone according to claim 5, wherein The hydrocyclone has a top end, and wherein the at least one nozzle dilution port is angled towards the top end of the hydrocyclone.

8. The hydrocyclone according to claim 5, wherein The middle part includes two spaced-apart housings, and the fluid injection member is adapted to be connected to the two housings.

9. The hydrocyclone according to claim 5, wherein, The injection member is located at least 30% of the total length of the hydrocyclone upward from the top end of the hydrocyclone.

10. A hydrocyclone having a middle part and a fluid injection member, the middle part having a longitudinal axis and a radius, the fluid injection member being adapted to be connected to the middle part, the injection member having at least two spaced-apart dilution ports, the dilution ports being angled relative to the middle part radius to cause fluid to enter with both a tangential velocity component and a radial velocity component.

11. The hydrocyclone according to claim 10, wherein, One dilution port injects fluid into the middle part in one direction, while the other dilution port injects fluid into the middle part in a different direction.

12. The hydrocyclone according to claim 10, wherein, The hydrocyclone has a top end, and wherein the nozzle dilution port is angled between 0 and 75 degrees relative to the longitudinal axis of the hydrocyclone towards the top end of the hydrocyclone.

13. The hydrocyclone according to claim 10, wherein, The middle part includes two spaced-apart housings, and the fluid injection member is adapted to be connected to the two housings.

14. The hydrocyclone according to claim 10, wherein, The nozzle is adapted to be attached to the nozzle housing such that the injection directions of the two dilution ports are both in a direction perpendicular to the longitudinal axis of the hydrocyclone.

15. The hydrocyclone according to claim 10, wherein The injection member is located at least 30% of the total length of the hydrocyclone upward from the top end of the hydrocyclone.

16. The hydrocyclone according to claim 10, wherein, One dilution port is angled relative to the middle part radius by one angle, while the other dilution port is angled relative to the middle part radius by another angle.

17. The hydrocyclone according to claim 10, wherein One dilution port is angled relative to the longitudinal axis of the middle part by one angle, and the other dilution port is angled relative to the longitudinal axis of the middle part by another angle.

18. The hydrocyclone according to claim 10, wherein, The nozzle has at least one dilution port passing through the nozzle, the dilution port being angled relative to the radius of the middle portion and not perpendicular to the longitudinal axis of the middle portion.

19. The hydrocyclone according to claim 10, wherein, The fluid injection member is adapted to be releasably connected to the middle portion.

20. A hydrocyclone having a top end and having a middle portion, a fluid injection member, and at least one dilution port passing therethrough, the middle portion having a longitudinal axis and a radius, the fluid injection member being connected to the middle portion, the fluid injection member having a dilution channel passing therethrough, the dilution port being angled between 0 and 75 degrees relative to the longitudinal axis of the middle portion and between 5 and 75 degrees relative to the radius of the middle portion, such that fluid enters with both a tangential velocity component and a radial velocity component.

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