WO2024191294A1

WO2024191294A1 - Separator device and method for separating a material to be separated into solid material and liquid

Info

Publication number: WO2024191294A1
Application number: PCT/NL2024/050119
Authority: WO
Inventors: Pieter VISSCHER; Lubbertus VAN DEN BRINK
Original assignee: Visscher Separators BV
Current assignee: Visscher Separators BV
Priority date: 2023-03-13
Filing date: 2024-03-11
Publication date: 2024-09-19
Anticipated expiration: 2025-09-13
Also published as: NL2034326B1

Abstract

The invention relates to a separator device for separating solids and liquids, wherein the separator device comprises: A housing which is provided with an infeed. A rotatable screw conveyor arranged in the housing and provided with an infeed end for carrying along material to be separated and an outfeed end for outfeed of solid material, a drainage screen arranged around the screw conveyor, and a support bearing arranged in the housing and around the screw conveyor, wherein the drainage screen and the support bearing define a separator space arranged around the screw conveyor.

Description

SEPARATOR DEVICE AND METHOD FOR SEPARATING A MATERIAL TO BE SEPARATED INTO SOLID MATERIAL AND LIQUID

The present invention relates to a separator device for separating solids and liquids. The invention further relates to a method for separating a material to be separated into solid material and liquid.

Separator devices are known in practice. The known separator devices are provided with an infeed into which a material to be separated can be fed. The material to be separated is then fed into a separator space by a screw conveyor. Usually present in the separator space is a screen which is arranged all around the screw conveyor. The screw conveyor can be driven by a drive which is configured to rotate the screw conveyor about a rotation axis. By adding sufficient material to be separated into the separator space the liquid is carried through the screen and out of the separator space, after which the solid material remains in the separator space. The solid material can then fall out of the separator device at an end of the separator space.

A drawback of the known separator devices is that the central shaft of the screw conveyor will start to bend due to the force acting on the screw conveyor. This results in the screw ribbon of the screw conveyor pressing against the screen, which increases wear to the screen and/or the screw ribbon. The screw ribbon can also come to rotate against other components of the separator device present in the housing. This reduces the lifespan of the separator device.

The present invention has for its object to obviate or at least reduce the above stated problems. It can be a particular object of the invention to provide a separator device with reduced wear to the spring.

This object is achieved with a separator device for separating solids and liquids, wherein the separator device comprises: a housing which is provided with an infeed; a rotatable screw conveyor arranged in the housing and provided with an infeed end for carrying along material to be separated and an outfeed end for outfeed of solid material; a drainage screen arranged around the screw conveyor; and a support bearing arranged in the housing and around the screw conveyor, wherein the drainage screen and the support bearing define a separator space arranged around the screw conveyor.

An advantage of the support bearing is that the screw conveyor remains better centred. The improved centring of the screw conveyor greatly reduces wear to the components of the separator device, particularly of the drainage screen. This has the advantageous effect that the separator device has a longer lifespan. The maintenance costs are alternatively or additionally reduced. Yet another advantage is that the efficiency of the separation is increased, since less material to be separated can become stuck between the screw conveyor and the drainage screen. This increases the efficiency of the separator device according to the invention.

The drainage screen and support bearing preferably define a separator space, wherein the inner surface of the separator space is preferably positioned enclosing the screw conveyor. The separator space is the space in which at least a part of the screw conveyor is positioned and is configured to rotate in. The material to be separated is fed into the separator space by the rotation of the screw conveyor. Because the material to be separated is also pressed outward by the screw conveyor during rotation, the liquid material can be discharged from the separator space through the drainage screen. The solid material of the material to be separated will hereby remain behind in the separator space, whereby the material to be separated is separated into a liquid fraction and solid fraction.

The separator device preferably comprises a drive which is configured to rotate the screw conveyor.

The screw conveyor can also be understood to mean a screw or a spindle. In an embodiment the screw conveyor comprises a shaft on which a screw ribbon is provided. The infeed is configured to admit material to be separated from outside the housing into the separator space. The support bearing is preferably arranged enclosing the screw conveyor. In the context of the present application enclosing is understood to mean that the circumference of the support bearing is substantially equal to the circumference of the screw ribbon of the screw conveyor.

The position of the support bearing is directly behind or adjacent to the drainage screen. Alternatively or additionally, the support bearing is positioned at the end of the screw ribbon. Support bearing can also be understood to mean a slide bearing.

In an embodiment according to the invention the separator device further comprises a press screen arranged at the outfeed end of the screw conveyor, wherein the support bearing is positioned between the drainage screen and the press screen.

The drainage screen, the support bearing and the press screen preferably together define the separator space. In an embodiment the separator space is further defined by a press chamber and a press end. The press chamber and press end are preferably the end of the separator space which are positioned at the outfeed end of the screw conveyors.

An advantage of the press screen positioned at the outfeed end of the screw conveyor is that the material to be separated effectively excretes its liquid through the press screen. This is realized in that the screw conveyor displaces the material to be separated in the direction of the press screen, to the outfeed end of the screw conveyor. The material to be separated is collected in the vicinity of the press screen, whereby the pressure is built up by additional infeed of material to be separated. Due to this built-up pressure, the liquid is effectively pressed out of the material to be separated and through the press screen.

In an embodiment according to the invention the separator device further comprises two screw conveyors arranged parallel to each other.

The capacity of the separator device is increased by the screw conveyors arranged parallel to each other.

In an embodiment according to the invention a first of the two screw conveyors rotates in anti-clockwise direction and a second of the two screw conveyors rotates in clockwise direction.

The screw conveyors optionally counter-rotate. An advantage of an anti -clockwise and clockwise screw conveyor is that the screw conveyors clean each other, as it were, by the screw threads or screw ribbons of the individual screw conveyors being positioned partially in each other. This reduces the chance of blockages. The screw conveyors are preferably positioned adjacently of each other.

The distance between the screw ribbons of the two individual screw conveyors lies in the range of 0. 1-5 centimetres, preferably in the range of 0. 1-2 centimetres, and most preferably in the range of 0. 1-1 centimetres, as seen in a direction perpendicularly of the shaft of the screw conveyors. An effective mutual cleaning between the screw conveyors is hereby achieved. The distance between the two individual screw conveyors is preferably as small as possible, or minimal.

In an embodiment according to the invention the support bearing comprises a fixed support bearing part and a readjustable support bearing part, wherein the readjustable support bearing part is readjustable in a direction substantially perpendicularly of a rotation axis of the screw conveyor.

The readjustable support bearing part is preferably positioned at the position where most wear to the support bearing part occurs. In the embodiment in which two screw conveyors positioned parallel are provided, the readjustable support bearing parts are the laterally oriented parts. Laterally oriented parts are understood to mean the parts of the support bearing which cross a first plane which is defined by the two parallel shafts of the screw conveyors. The readjustable support bearing part is preferably adjustable in a direction parallel to the first plane.

The readjustable support bearing part makes it possible to adjust the support bearing to once again enclose the screw conveyors. This is advantageous when the readjustable support bearing part has become worn, which could result in clearance between the support bearing and the screw conveyor. The readjustable support bearing part reduces the clearance in the support bearing. As a result, the screw conveyors are centred better. This reduces wear to the components, particularly the screens.

In an embodiment according to the invention the readjustable support bearing part is connected to adjusting means for adjusting the readjustable support bearing part. With the adjusting means the readjustable support bearing part can be automatically adjusted in simple manner. This obviates the need for the user to adjust the readjustable support bearing part themselves. This increases the convenience of use. Alternatively or additionally, adjusting of the readjustable support bearing part is hereby carried out more accurately.

The adjusting means preferably comprise hydraulic adjusting means.

In an embodiment according to the invention the separator device further comprises at least one bearing sensor arranged in the separator space and configured to measure clearance in the support bearing, wherein the adjusting means are configured to adjust the readjustable support bearing part on the basis of the measurement of the at least one bearing sensor.

A fully automatic system can be obtained with the bearing sensor in combination with the adjusting means. This has the advantage that the support bearing is substantially always positioned enclosing the screw conveyors, which prevents wear.

In an embodiment according to the invention the separator device further comprises a hollow drainage pipe arranged against the outfeed end and provided with drainage holes, and configured to discharge water from a centre of the separator space out of the separator space.

The drainage pipe is preferably arranged in line with the shaft of the screw conveyor. The drainage holes are arranged in the periphery of the hollow drainage pipe. The drainage holes hereby provide a liquid passage from outside the drainage pipe to the hollow inside of the drainage pipe-

An advantage of the drainage pipe is that, owing to the drainage holes, liquid can also be removed from the middle, or in other words the centre, of the material to be separated. Hereby, the drainage pipe functions as it were as an internal screen, wherein the press screen can be seen as external screen. Separating into liquid and solid material of the material to be separated is accelerated by the drainage pipe.

The invention further relates to a hollow drainage pipe which is provided with drainage holes and which is configured to discharge water from a middle of the separator space out of the separator space.

The drainage holes are arranged in the periphery of the hollow drainage pipe. The drainage holes hereby provide a liquid passage from outside the drainage pipe to the hollow inside of the drainage pipe.

The drainage pipe is configured to be arranged against an outfeed end of a screw conveyor, wherein the screw conveyor is preferably arranged in a separator device. The drainage pipe is preferably placed in line with the shaft of the screw conveyor.

In an embodiment according to the invention a cutting plate for cutting the material to be separated is provided at an inlet of the separator space. The cuting plate preferably has the circumference of the separator space. The cuting plate is further preferably cylindrical.

The cuting plate already reduces the material to be separated before it is carried into the separator space. This reduces the chance of material blockages between the screens and the screw conveyor.

The cuting plate optionally takes a double-sided form. Double-sided form means that the cuting plate is arranged on the inner side and the outer side of the infeed of the separator space. This improves operation of the cuting plate, since the material to be separated is cut into smaller pieces.

In an embodiment the cuting plate is self-hardening and/or made of wear-resistant material, preferably of a material with a great hardness.

The self-hardening and/or wear-resistant material extends the lifespan of the cuting plate.

In an embodiment according to the invention the circumference of the cuting plate substantially corresponds with the circumference of the infeed of the separator space.

Hereby, the throughfeed area of the cuting plate is not reduced, while the excessively large pieces of the material to be separated are reduced.

In an embodiment according to the invention the housing comprises a releasable cover which, in a released state, provides access to the separator space.

Removing the releasable cover provides access to the separator space. This makes the separator space, and particularly the drainage screen and the press screen, simple to clean. The releasable cover is preferably positioned on the upper side of the housing.

In an embodiment according to the invention openings in the drainage screen and/or press screen are trapezoidal as seen in a direction parallel to a length of the screw conveyor.

The opening is trapezoidal, wherein two sides of the trapezium are preferably positioned substantially parallel. The two sides positioned parallel are preferably oriented perpendicularly of a radial direction of the screw conveyor. A proximal side is preferably positioned closer to the screw conveyor than a distal side. The proximal side and distal side of the opening are preferably connected by two side walls which extend flaring outward as seen from the screw conveyor. The proximal side is here shorter than the distal side.

Due to the inverse, outward-directed trapezoidal form, there is no narrowing in the opening. This reduces the chance of blockage by dirt and/or solid material in the openings. This increases the efficiency of the removal of liquid from the material to be separated.

In an embodiment according to the invention the screw conveyor comprises a screw ribbon on which tungsten carbide is provided.

The tungsten carbide is preferably welded onto the screen ribbon. Alternatively or additionally, the screw ribbon is sharpened. Providing tungsten carbide on the screw ribbon limits wear as far as possible. Alternatively or additionally, tungsten carbide is also welded onto the flanks of the screw conveyor. This also limits wear to the flanks as far as possible.

In an embodiment according to the invention the drainage screen and/or the press screen are made of a material with a hardness greater than 200 HB, preferably with a hardness greater than 300 HB, more preferably a hardness greater than 400 HB and most preferably a hardness greater than 600 HB.

The material preferably comprises Creusabro. Said hardnesses greatly reduce wear to the screens, this extending the lifespan of the separator device as a whole.

In an embodiment according to the invention a support cage for supporting the drainage screen and/or the press screen is provided around the drainage screen and/or the press screen.

The support cage holds the screen stably in its most advantageous position. Alternatively or additionally, the chance of seams in the separator space is reduced.

In an embodiment according to the invention the separator device further comprises a liquid outfeed for discharging liquid pressed out through the drainage screen and/or press screen.

In an embodiment according to the invention the housing is substantially free of welded seams.

The absence of welded seams results in a stronger construction of the separator device. A further advantage of the absence of welded seams is that the separator device can be taken apart for repairs and/or maintenance more easily.

The invention further relates to a spray lance for cleaning the device. The invention relates to a separator system comprising: a separator device according to the invention; and a spray lance for cleaning the separator device.

The drainage screen and the press screen can be cleaned in simple manner with the spray lance, without the drainage screen and the press screen having to be removed from the housing.

In an embodiment according to the invention a press end is provided at an end of the separator space. The press end is configured to obstruct the solid material being carried to the end of the separator space by the screw conveyors. The press end further provides the option of removing the solid material from the separator space. For this purpose the press end is configured to be selectively opened. In an embodiment according to the invention a press chamber is provided between the press end and the press screen.

In the context of the present invention it is possible to use different types of press end. Examples of suitable press ends are a spring-loaded press end, a manual end with counter-weight control, valves operated by cylinders, or an automatic press end as described in the patent application with the patent number EP 2 758 230 A1. The invention further relates to a method for separating a material to be separated into solid material and liquid, wherein the method comprises of: providing a separator device according to the invention; feeding material to be separated into the infeed; and separating the material to be separated into solid material and liquid by rotating the screw conveyor.

The method has similar advantages and effects as described for the separator device.

Further features, advantages and details of the invention are described on the basis of embodiments thereof, wherein reference is made to the accompanying drawings, in which: figure 1 is a perspective view of a separator device according to the invention; figure 2 is a schematic side view of a separator device according to the invention; figure 3 is a perspective view of a separator space; figure 4 is a view of a screen part; and figure 5 is a perspective view of a support bearing.

In the shown embodiment separator device 2 (figure 1) is provided with infeed 4. Infeed 4 comprises hopper 6. Hopper 6 is provided with feed conduit 8 whereby the material to be separated can be supplied. Vent 9 is further arranged on the upper side of hopper 6. Excess gas, for instance air, can be vented from hopper 6 through vent 9. Provided on the side of 6 is overflow 10. Overflow 10 is configured, when too much material to be separated is supplied through feed conduit 8, to discharge the excess material to be separated from hopper 6. A skilled person will appreciate that separator device 2 can also be used without hopper 6, whereby the material to be separated is placeable directly through an infeed hole provided in housing 12.

Housing 12 is provided with removable cover 14 on upper side 16 of separator device 2. Removable cover 14 is releasable from the rest of housing 12 by means of locking elements 18. The inner space of housing 12 of separator device 2 is hereby readily accessible, for instance for cleaning thereof. In order to remove removable cover 14 from housing 12 two handles 15 are arranged thereon. Provided on front 20 of housing 12 of separator device 2 is drive 22. Provided on the underside 21 of housing 12 are two legs 24, each with two feet 26. Housing 12 is hereby positioned at a height Hi relative to ground surface 28.

Separator device 2 (figure 2) comprises infeed 4 in which the material to be separated is fed into housing 12. Two screw conveyors 30 are arranged in housing 12. Screw conveyor 30 extends from infeed end 31 to outfeed end 33. Screw conveyor 30 comprises shaft 32 and screw ribbon 34 arranged thereon. Screw conveyors 30 are operatively connected to drive 22 so that drive 22 can rotate screw conveyors 30. In housing 12 drainage screen 36, support bearing 38 and press screen 40 define separator space 42. Drainage screen 36 and press screen 40 are arranged in respective screen cages 37 and 41 so that drainage screen 36 and press screen 40 are strengthened. Screw ribbon 34 of screw conveyor 30 is positioned fittingly against drainage screen 36 and support bearing 38. This has the result that there is no space between the end of screw ribbon 34 and the periphery of separator space 42. This prevents material to be separated from being fed back between screw ribbon 34 and the periphery of separator space 42.

Drainage pipe 44 is arranged against outfeed end 33 of screw conveyor 30. Drainage pipe 44 comprises hollow pipe 46 in which drainage holes 48 are arranged. In the shown embodiment hollow pipe 46 has a diameter substantially equal to shaft 32 of screw conveyor 30. Arranged behind support bearing 38 is press screen 40. In press chamber 50, which is positioned downstream of press screen 40, the pressure is built up. This is realized by press end 52 which forms the rear wall of separator space 42 and can be selectively closed and (partially) opened.

Housing 12 is provided with first receptacle 58 for receiving liquid material removed from the material to be separated. First receptacle 58 can be detachable attached to rest of housing 12 by means of a rails. In this way the inside of separator device 2 is easily accessible from below for cleaning and/or maintenance. The liquid can be discharged from first receptacle 58 by means of discharge pipe 56. Housing 12 further comprises protective cover 54 for receiving liquid from the drainage pipes. Protective cover 54 has a liquid connection, for instance a conduit (not shown), to first receptacle 58. Solid material can be pressed out of press chamber 50 by (partially) opening press end 52. Solid material can then drop downward freely, for instance onto a conveyor belt or container arranged under press end 52.

Separator space 42 (figure 3) is defined by drainage screen 36, support bearing 38 and press screen 40. A cross-section of a part of the periphery of drainage screen 36 is shown in detail in figure 4. Screw conveyors 30a, 30b protrude through separator space 42. Screw conveyors 30a, 30b have a respective length L and L’. In the shown embodiments longitudinal axis L and L’ are also the rotation axes. Screw conveyor 30a rotates in anti-clockwise direction and screw conveyor 30b rotates in clockwise direction.

Support bearing 38 comprises fixed bearing part 60 and readjustable bearing parts 62, 64. Readjustable bearing parts 62, 64 are positioned on sides of support bearing 38. Readjustable support bearing part 62 is adjustable in direction A and readjustable support bearing part 64 in direction B by means of hydraulic drive means 66.

A part of a periphery of drainage screen 36 is shown in figure 4. Drainage screen 36 is constructed from annular support ribs 68. Trapezoidal longitudinal ribs 70 are arranged on annular support ribs 68. Longitudinal ribs 70 extend in a direction parallel to longitudinal direction L of screw conveyors 30. Trapezoidal longitudinal ribs 70 have proximal wall 72 and distal wall 74, these running substantially parallel. In the shown embodiment proximal wall 72 is substantially twice as short as distal wall 74. Two side walls 76a, 76b extend tapering toward distal wall 74 from proximal wall 72. This has the result that openings 78 in drainage screen 6 flare outward. This reduces the chance of openings 78 becoming blocked.

Support bearing 38 (figure 5) comprises fixed bearing part 60 and readjustable bearing parts 62, 64. Readjustable bearing parts 62, 64 are positioned on sides of support bearing 38. Readjustable support bearing part 62 is adjustable in direction A and readjustable support bearing part 64 in direction B by means of hydraulic drive means 66. Hydraulic drive means are also configured to move readjustable support bearing part 62 in direction B and readjustable support bearing part 64 in direction A. In practice, drive means 66 usually move readjustable support bearing part 62 in direction A because inner wall 62a becomes worn due to screw conveyor 30a. Moving readjustable support bearing part 62 in direction A makes support bearing 36 enclose screw conveyor 30a again so that the chance of material remaining behind between support bearing 36 and screw conveyor 30a is reduced. Readjustable support bearing part 64 works in the same way, with the difference that support bearing part 64 is moved in direction B because inner wall 64a becomes worn due to screw conveyor 30b. Further arranged is bearing sensor 67. Bearing sensor 67 is operatively connected to drive means 66, whereby drive means 66 can readjust readjustable support bearing parts 62, 64 on the basis of the wear measured by bearing sensor 67.

In an embodiment according to the invention material to be separated is fed into feed conduit 8 of hopper 6. The material to be separated thereby comes to he at infeed end 31 of screw conveyors 30. Screw conveyors 30 are rotated by drive 22, whereby the material to be separated is carried into separator space 42 by screw ribbon 34. In separator space 42 the liquid fraction is first pressed out of the material to be separated by drainage screen 36 arranged in screen cage 37. Support bearing 38 is arranged enclosing screw conveyors 30 so that wear to drainage screen 36 and press screen 40 is reduced. The material to be separated is carried on to press screen 40, where the liquid fraction is pressed out of the material to be separated further. Following this, the material to be separated is pressed further on to press chamber 50. Located in press chamber 50 is press end 52 which serves as rear wall of separator space 42. Arranged in the centre of press screen 40 and press chamber 50 is drainage pipe 44, which is provided with drainage holes 48. The liquid fraction present in the middle of the material to be separated is hereby carried into the hollow inside of drainage pipe 44 and removed from the material to be separated. The solid fraction of the material to be separated then remains, and can subsequently be removed from separator space 42 by opening press end 52.

The present invention is by no means limited to the above described embodiments thereof. The rights sought are defined by the following claims, within the scope of which many modifications can be envisaged.

Claims

1. A separator device for separating solids and liquids, comprising: a housing which is provided with an infeed; a rotatable screw conveyor arranged in the housing and provided with an infeed end for carrying along material to be separated and an outfeed end for outfeed of solid material; a drainage screen arranged around the screw conveyor; and a support bearing arranged in the housing and around the screw conveyor, wherein the drainage screen and the support bearing define a separator space arranged around the screw conveyor.

2. Separator device according to claim 1, further comprising a press screen arranged at the outfeed end of the screw conveyor, wherein the support bearing is positioned between the drainage screen and the press screen.

3. Separator device according to claim 1 or 2, further comprising two screw conveyors arranged parallel to each other.

4. Separator device according to claim 3, wherein a first of the two screw conveyors rotates in anti -clockwise direction and a second of the two screw conveyors rotates in clockwise direction.

5. Separator device according to any one of the foregoing claims, wherein the support bearing comprises a fixed support bearing part and a readjustable support bearing part, wherein the readjustable support bearing part is readjustable in a direction substantially perpendicularly of a rotation axis of the screw conveyor.

6. Separator device according to claim 5, wherein the readjustable support bearing part is connected to adjusting means for adjusting the readjustable support bearing part.

7. Separator device according to claim 6, further comprising further comprising at least one bearing sensor arranged in the separator space and configured to measure clearance in the support bearing, wherein the adjusting means are configured to adjust the readjustable support bearing part on the basis of the measurement of the at least one bearing sensor.

8. Separator device according to any one of the foregoing claims, further comprising a hollow drainage pipe arranged against the outfeed end and provided with drainage holes, and configured to discharge water from a centre of the separator space out of the separator space.

9. Separator device according to any one of the foregoing claims, wherein a cutting plate for cutting the material to be separated is provided at an inlet of the separator space.

10. Separator device according to claim 9, wherein the circumference of the cutting plate substantially corresponds with the circumference of the infeed of the separator space.

11. Separator device according to any one of the foregoing claims, wherein the housing comprises a releasable cover which, in a released state, provides access to the separator space.

12. Separator device according to any one of the foregoing claims, wherein openings in the drainage screen and/or press screen are trapezoidal as seen in a first direction.

13. Separator device according to any one of the foregoing claims, wherein the screw conveyor comprises a screw ribbon on which tungsten carbide is provided.

14. Separator device according to any one of the foregoing claims, wherein a support cage for supporting the drainage screen and/or the press screen is provided around the drainage screen and/or the press screen.

15. Separator device according to any one of the foregoing claims, wherein the housing is substantially free of welded seams.

16. Method for separating a material to be separated into solid material and liquid, comprising of: providing a separator device according to any one of the claims 1-15; feeding material to be separated into the infeed; and separating the material to be separated into solid material and liquid by rotating the screw conveyor.