WO2004020069A1

WO2004020069A1 - Sedimentation unit, lamellar plate, sedimentation plant and method for separation

Info

Publication number: WO2004020069A1
Application number: PCT/SE2003/001358
Authority: WO
Inventors: Henric Lind
Original assignee: Polyproject Sweden Ab
Priority date: 2002-09-02
Filing date: 2003-09-01
Publication date: 2004-03-11
Also published as: SE0202626L; AU2003257749A1; SE0202626D0; SE523974C2

Abstract

The present invention relates, inter alia, to a sedimentation unit (1) for separating solid particles or the like from a flowing fluid containing such particles, wherein the unit (1) includes at least one lamellate pack (2) and at least one outlet channel (3), and wherein the lamellate pack (2) shows at least one inlet (15) for said particle containing fluid, at least one first outlet (16) for fluid that is substantially free of such particles, and at least one second outlet (17) for separated particles. The sedimentation unit (1) is characterised in that the lamellate pack (2) includes at least two flanged, generally planar lamellar plates (4) which are joined together to form a unit and which together define at least one channel for said flowing fluid, said channel sloping obliquely upwards from said inlet (15) to said first outlet (16) when the sedimentation unit (1) is in use.

Description

SEDIMENTATION UNIT, LAMELLAR PLATE, SEDIMENTATION PLANT, AND METHOD FOR SEPARATION

The present invention relates to a sedimentation unit for separating from a flowing fluid solid particles or the like present in said fluid, wherein the unit includes at least one lamellate pack and at least one outlet channel, and wherein the lamellate pack shows at least one particle-carrying fluid inlet, at least one first outlet for said fluid that is substantially free of particles, and at least one second outlet for separated particles. The invention also relates to a lamellar plate, a sedimentation plant and a method for separation.

Prior art

Solid particles are traditionally separated from fluids in for instance sewage purification plants with the aid of different types of sedimentation tanks. One drawback with such tanks is that they take-up large volumes/areas of space. With the intention of reducing the size of these volumes/areas, there have been proposed different forms of sedimentation devices that include the use of different forms of flow channels for particle-laden fluids. These flow channels are often expensive to produce, due to their complexity, and strong supportive constructions are often required for supporting proposed sedimentation devices in basins or the like. Orientation of the channels for incoming and outgoing fluids around the actual sedimentation section may also be complicated and also often requires fluids to be pumped in order to achieve suitable fluid flow through the sedimentation devices.

Summary of the invention

A first object of the present invention is to provide a sedimentation unit which comprises flow channels that are formed relatively simply and that by virtue of being self-supporting do not require the provision of a strong supportive construction. The sedimentation unit has simple channel orientation around the actual sedimentation section of the unit and does not require fluids to be pumped, wherewith the unit is, on the whole, cheap to produce and flexible in use. A second object of the invention is to provide a lamellar plate for use in a sedimentation unit according to the invention. A third object of the invention is to provide a sedimentation plant based on the inventive sedimentation unit. A fourth object of the invention is to provide a method of separating from a flowing fluid solid particles or the like present in said fluid, with the aid of the inventive sedimentation unit.

Accordingly, the invention relates to a sedimentation unit for separating from a flowing fluid solid particles or the like present in the fluid, wherein the unit includes at least one lamellate pack and at least one outlet channel, and wherein the lamellate pack shows at least one inlet for the mentioned particle-containing fluid, at least one first outlet for the mentioned fluid mainly without particles and at least one second outlet for separated particles. The lamellate pack includes at least two flanged generally planar lamellar plates which are joined together to form a unit and which together define at least one channel for said flowing fluid, said channel being inclined obliquely upwards from said inlet to said first outlet when the sedimentation unit is used.

The lamellate pack may also include a generally planar covering plate which in combination with said lamellar plates defines the same number of channels for said flowing fluid as the number of lamellar plates present in the lamellate pack, wherein said lamellate pack also shows as many of each of said inlet, first outlet and second outlet as there are lamellar plates in the lamellate pack. Each lamellar plate may be generally rectangular in shape and provided with a continuous flange along each of two of its edges. The continuous flange may extend generally at right angles to said lamellar plate on its front side, such that said lamellar plate and its two flanges define a channel of U-profile. The lamellar plates may be placed adjacent to each other in the lamellate pack such that all flanges will face in mutually the same direction, wherewith with the exception of the edges of one of said lamellar plates the edges of remaining plates abut with and are permanently attached to the rear side of the adjacent lamellar plate, and wherewith the edges of the flanges on one of said plates abut with and are permanently attached to the adjacent mentioned covering plate. At least one of the mentioned flanges may be provided with at least one indentation in that part of the flange which is located nearest to the mentioned first outlet when the sedimentation unit is in use.

Each of said inlets may be identical to each of the respective mentioned second outlets. The lamellar plates may be comprised of steel sheet or the like with a material thickness of 0.3-1.0 mm, preferably 0.5-0.75 mm. The lamellar plates may be comprised of a plastic material or the like with a material thickness of 1.5-3.0 mm, preferably 2.0-2.5 mm.

Each of the mentioned fluid conducting channels, which are upwardly inclined from said inlet to said first outlet when the sedimentation unit is in use, may slope to the horizontal at an angle of 45-70 degrees, preferably 55-60 degrees. The mentioned outlet channel can enable fluid leaving said first outlet to flow to and through at least one opening in said outlet channel. The mentioned opening in said outlet channel may be provided with at least one pipe connection for connection to a further pipe or the like. The mentioned outlet channel may be comprised of sheet steel or the like, with a material thickness of 1.5-3.5 mm, preferably 2.0-3.0 mm. The mentioned outlet channel may be made of a plastic material or the like with a material thickness of 5.0-7.0 mm, preferably 6.0 mm.

At least one attachment device may be included for hanging and/or fastening the sedimentation unit in a sedimentation plant, such as a sedimentation tank or the like. Two attachment devices may be included, of which a first attachment device is located downwardly of and forwardly of the lamellate pack adjacent said inlet when the sedimentation unit is in use, whereas a second one of the mentioned attachment devices is located upwardly of and rearwardly of the lamellate pack adjacent said first outlet.

The invention also relates to a lamellar plate for use in a sedimentation unit in accordance with the above stated. The plate is generally rectangular in shape and includes a continuous flange along each of two of its edges, wherein said flange extends generally at right angles to said plate on the front side thereof such that the mentioned lamellar plate and its two flanges define a channel of U- profile. The invention also relates to a sedimentation plant that includes at least one sedimentation unit in accordance with the above stated, and also to a method of separation from a flowing fluid solid particles or the like present in said fluid, said separation being effected with the aid of a sedimentation unit according to the above stated. List of drawings

Figure 1 shows, in a perspective view, a sedimentation unit according to the invention. Figure 2a shows, in a side view, partially in section, a sedimentation unit according to the invention.

Figure 2b shows, in a view from above, the sedimentation unit of Figure 2a.

Figure 2c shows, in a front view, the sedimentation unit in Figure 2a.

Figure 3a shows, in a side view, a lamellar plate included in the sedimentation unit in Figure 2a. Figure 3b shows, in a front view, the lamellar plate in Figure 3a.

Figure 3c shows, in a view from above, the lamellar plate in Figure 3a. Figure 3d shows, in a perspective view, the lamellar plate in Figure 3a. Figure 4a shows, in a side view, an end plate with a front attachment device included in the sedimentation unit in Figure 2a. Figure 4b shows, in a front view, the end plate with the front attachment device in Figure 4a. Figure 4c shows, in a view from above, the end plate with the front attachment device in Figure 4a. Figure 4d shows, in a perspective view, the end plate with the front attachment device in Figure 4a.

Figure 5a shows, in a side view, a rear attachment device included in the sedimentation unit in Figure 2a. Figure 5b shows, in a front view, the rear attachment device in Figure 5a. Figure 5c shows, in a view from above, the rear attachment device in Figure 5a.

Figure 5d shows, in a perspective view, the rear attachment device in Figure

5a. Figure 6a shows, in a perspective view, a first embodiment of an outlet channel included in the sedimentation unit in Figure 2a. Figure 6b shows, in a perspective view, a second embodiment of an outlet channel included in the sedimentation unit in Figure 2a. Figure 6c shows, in a perspective view, a third embodiment of an outlet channel included in the sedimentation unit in Figure 2a. Figure 7 shows, in a side view, partly in section, a part of a sedimentation plant according to the invention with an inventive sedimentation unit.

Description of embodiments Figures 1 and 2a-2d illustrate a sedimentation unit 1 comprising a lamellate pack 2 and an outlet channel 3. The lamellate pack 2 includes a number of lamellar plates 4 - more specifically 23 plates 4 in the embodiment according to Figure 2a and somewhat more plates in the embodiment according to Figure 1 , wherein said lamellar plates 4 are provided with flanges and are planar therebetween. The flanges 5 of the lamellar plates 4 show V-shaped indentations 6. The lamellate pack 2 also includes an end plate 7 without any flanges. Also included is a front attachment device 8 and a rear attachment device 9 for suspending and/or fastening the sedimentation unit 1 in a sedimentation plant, such as a basin or the like. The outlet channel 3 shows an opening 10 having a pipe connection 11.

As will be seen from figures 3a-3d, each lamellar plate 4 is rectangular in shape and provided with a continuous flange 5 along each one of two of its sides, more specifically along two mutually opposite sides and along the full length of the sides. The flanges 5 extend at right angles to the major part of the lamellar plate 4 and mutually in the same direction relative to the main extension plane of the plate, such that a lamellar plate 4 and its two flanges 5 define a channel of U- profile. The lamellar plates 4 are stacked adjacent to/on top of each other with all flanges facing in the same direction - to the left in figure 2a although they might equally as well face towards the right. The edges of the flanges of each one of the respective lamellar plates 4, with the exception of one plate, abut with the rear side of the respective adjacent plates, i.e. the side that forms the underside of the aforesaid U-profile, wherein said edges consist of the thin edge comprised of the material thickness of said flanges. The corresponding edges of the flanges 5 of the remaining lamellar plate 4 are, instead, in abutment with the adjacent end plate 7. Each flange 5 abuts an adjacent plate along its full length and the flanges 5 are permanently joined to respective adjacent plates as by welding, soldering, brazing, gluing or in some other suitable fashion. The join may moreover be strengthened or replaced with laminates applied over joints. Thus, there is formed a channel for flowing fluid between each pair of adjacent plates. The indentations 6 are present in all flanges 5, so as to obtain a so-called dented skiboard in that part of the lamellate pack 2 at which it opens into the outlet channel 3.

As will be seen from figures 4a-4d, the end plate 7 is of the same size as the non-flanged part of the laminar plate 4. The front attachment device 8 on the end plate 7 is either fastened to the plate in some appropriate manner or formed in one piece with said plate. The construction of the rear attachment device 9 will be seen from figures 5a-5d. If the lamellar plates 4 in the lamellate pack are stacked adjacent to/on top of each other with all flanges 5 facing in the other direction, that is to the right in figure 2a, it will be necessary, of course, to place the end plate 7 at the rear end of the lamellate pack and for the end plate to co-act with the rear attachment device 9 instead. In this case, the ends of the flanges 5 nearest the lower edge of the lamellate pack are appropriately modified so that the lower edge will also be uniform in this case. The two attachment devices 8, 9 may have mutually the same design regardless of where the end plate 7 is situated in the lamellate pack, in other words both attachment devices may have the form of the illustrated front attachment device 8 or of the illustrated rear attachment device 9 and may, of course, be turned in a purposeful manner in all cases. Because of the rigid construction of the lamellate pack and because of the structural design of the lamellar plates 4, two attachment device points are sufficient with regard to mounting of the sedimentation unit 1 , i.e. one front/lower and one rear/upper attachment device.

Figures 6a and 6b illustrate alternative embodiments of the outlet channel 3 whereby figure 6a primarily but not exclusively concerns a design in a plastic material or the like while figure 6b primarily but not exclusively concerns a design of sheet steel or the like. The outlet channel 3 is comprised of a continuous channel of L-profile that extends along three sides of the lamellate pack in the upper end of said pack when using the sedimentation unit 1. The lower edge of said L-profile - by which is meant the thin edge consisting of the thickness of the channel material - abuts the lamellate pack and is permanently joined thereto as by welding, soldering, brazing, gluing or in some other appropriate fashion. In one alternative embodiment, the sedimentation unit 1 may, instead, be single-sided, and the outlet channel 3 of L-profile will thus solely occur on one side of the lamellate pack 2 which in such case would either be on the left or on the right side when the sedimentation unit 1 is seen as in figure 2c. Both the channel 3 to the left and the channel 3 to the right may, per se, be combined with a front channel 3 of L-profile and with or without an opening 10 and a pipe connection 11. That side of the lamellate pack 2 where there is no L-shaped outlet channel 3 is, instead, preferably provided with a cover sheet that makes uncontrolled leakage of cleansed fluid either difficult or impossible; see figure 6c in which a cover sheet is provided to the left. The flanges 5 nearest the cover sheet will preferably not include indentations 6.

The inventive sedimentation unit 1 is a complete module that can be installed readily in sedimentation plants of different kinds and sizes. Figure 7 illustrates a sedimentation unit 1 mounted in a part of a sedimentation basin, where the basin walls are referenced 12. The front attachment device 8 is fastened to the wall 12 in some suitable known manner, while the rear attachment device 9 is either fastened to a rear basin wall (not shown) or is held in position by the action of suitable braces or the like extending from the basin wall or bottom. The pipe connection 11 is connected to an outer conduit 13, which extends through the basin wall 12 and further out. The sedimentation unit 1 is immersed deeply into the surrounding basin-contained fluid, for instance water, although not completely. The fluid level in the sedimentation unit 1 will normally be 2-3 cm beneath the level 14 of the surrounding basin fluid. It is, of course, also possible to install several sedimentation units 1 in one and the same sedimentation plant.

The functioning of the sedimentation unit 1 will now be described in more detail with reference to figure 7. Fluid containing solid particles, for example water containing solid impurities, such as biological sludge, heavy metal precipitates or the like is pressed through the lamellate pack 2 by self-induced pressure and thus without pumping, wherein the fluid enters in the lower edge of the lamellate pack 2 in each of the plate interspaces and exits at the upper edge of said lamellate pack 2 through and possibly over the indentations 6 present in the pack. As it passes through the lamellate pack 2, the fluid is cleansed of impurities, which settle on the in profile U-shaped lamellar plates due to the gravitational effect and are caused to sink down through respective plate interspaces and further down to the basin bottom. Thus, each plate interspace shows a contaminated fluid inlet 15, a first outlet 16 for substantially cleansed fluid and a second outlet 17 for separated particles, wherein the same opening functions as inlet 15 and outlet 17. The cleansed fluid continues out along the outlet channel 3, through the opening 10 and the pipe connection 11 and through the external conduit 13.

The use of the inventive sedimentation unit enables the basin surface area required for sedimentation purposes to be reduced to about one-tenth of that required in respect of traditional basin sedimentation.

The invention is not restricted to the embodiments shown here but may be varied within the scope of the accompanying claims.

Claims

1. Sedimentation unit (1) for separating solid particles or the like from a flowing fluid containing such particles, which unit (1) includes at least one lamellate pack (2) and at least one outlet channel (3), wherein said lamellate pack (2) shows at least one inlet (15) for said particle-containing fluid, at least one first outlet (16) for fluid that is substantially free from particles, and at least one second outlet (17) for separated particles, characterised in that the lamellate pack (2) includes at least two flanged generally planar lamellar plates (4) which are joined together to form a unit and which together define at least one channel for said flowing fluid, said channel sloping obliquely upwards from said inlet (15) to said first outlet (16) when the sedimentation unit (1) is used.

2. Sedimentation unit (1) according to claim 1 , characterised in that the lamellate pack (2) also includes a generally planar cover plate (7) which together with said lamellar plates (4) define as many channels for said flowing fluid as there are lamellar plates (4) in said lamellate pack (2), wherein the lamellate pack (2) also shows as many of each of said inlet (15), first outlet (16) and second outlet (17) as there are lamellar plates (4) in said lamellate pack (2).

3. Sedimentation unit (1) according to any one of the preceding claims, characterised in that each said lamellar plate (4) is generally rectangular in shape and provided with a continuous flange (5) along each of two of its edges.

4. Sedimentation unit according to claim 3, characterised in that said continuous flange (5) extends generally at right angles to said lamellar plate (4) on the front side thereof, so that said lamellar plate (4) and its two flanges (5) define a U-profile channel.

5. Sedimentation unit (1) according to claim 4, characterised in that said lamellar plates (4) are juxtaposed in the lamellate pack (2) such that all flanges (5) will face in the same direction, wherein the edges of the flanges (5) on each of said lamellar plates (4), with the exception of one plate (4), abut with and are permanently joined to the rear side of the adjacent said lamellar plate (4) and the edges of the flanges (5) of one of said lamellar plates (4) abut with and are permanently joined to the adjacent said cover plate (7).

6. Sedimentation unit (1) according to any one of claims 3-5, characterised in that at least one of said flanges (5) is provided with at least one indentation (6) in that part of the flange (5) located nearest said first outlet (16) when the sedimentation unit (1) is in use.

7. Sedimentation unit (1) according to any one of the preceding claims, characterised in that each of said inlets (15) is the same as each of respective said second outlets (17).

8. Sedimentation unit (1) according to any one of the preceding claims, characterised in that said lamellar plates (4) are comprised of sheet steel or the like with a material thickness of 0.3-1.0 mm, preferably 0.5-0.75 mm.

9. Sedimentation unit (1) according to any one of claims 1-7, characterised in that said lamellar plates (4) are comprised of a plastic material or the like with a material thickness of 1.5-3.0 mm, preferably 2.0-2.5 mm.

10. Sedimentation unit (1) according to any one of the preceding claims, characterised in that each of said channels for said flowing fluid, said channel obliquely sloping upwards from said inlet (15) to said first outlet (16) when the sedimentation unit (1) is in use, slope at an angle of 45-70 degrees, preferably 55- 60 degrees to the horizontal.

11. Sedimentation unit (1) according to any one of the preceding claims, characterised in that the mentioned outlet channel (3) enables fluid exiting from said first outlet (16) to flow to and through at least one opening (10) in said outlet channel (3).

12. Sedimentation unit (1) according to claim 11 , characterised in that the mentioned opening (10) in said outlet channel (3) is provided with at least one pipe connection (11) for connection to a further pipe (13) or the like.

13. Sedimentation unit (1) according to any one of claims 11 and/or 12, characterised in that said outlet channel (3) is comprised of sheet steel or the like with a material thickness of 1.5-3.5 mm, preferably 2.0-3.0 mm.

14. Sedimentation unit (1) according to any one of claims 11 and/or 12, characterised in that said outlet channel (3) is comprised of a plastic material or the like with a material thickness of 5.0-7.0 mm, preferably 6.0 mm.

15. Sedimentation unit (1) according to any one of the preceding claims, characterised by at least one attachment device (8, 9) for hanging and/or fastening the sedimentation unit (1) in a sedimentation plant, such as a sedimentation basin or the like.

16. Sedimentation unit (1) according to claim 15, characterised by two attachment devices (8, 9), wherein when the sedimentation unit (1) is in use, a first one (8) of said attachment devices is situated downwardly and forwardly of the lamellate pack (2) at said inlet (15), while a second one (9) of said attachment devices is situated upwardly and rearwardly of the lamellate pack (2) at said first outlet (16).

17. Lamellar plate (4) for use in a sedimentation unit (1) according to any one of the preceding claims, characterised in that the plate (4) is generally rectangular in shape and provided with a continuous flange (5) along each of two of its edges, wherein said flange (5) extends generally at right angles to said lamellar plate (4) on its front side, so that said lamellar plat (4) and its two flanges (5) define a U- profile channel.

18. Sedimentation plant, characterised in that it includes at least one sedimentation unit (1) according to any one of claims 1-16.

19. Method for separation of solid particles or the like from a flowing fluid containing such particles, characterised in that the separation is carried out with a sedimentation unit (1) according to any one of claims 1-16.