DK202100075U3 - Vertical or tangential vibrating vertical separator - Google Patents

Abstract

This invention describes a separator for separating solids from a slurry comprising a vertical vibrating vertical container, connected to a support through vibration dampers, where the vertical container is provided with at least a first inlet in the top and at least a first opening for retentate in the bottom and comprises at least one second opening for the filtrate. The first retentate can eighter by gravity move down to the first opening in the bottom of the vertical vibrating vertical container or by aeration with air or air enriched like first filtrate, by flotation, move to the top of first opening and by overflow drop down to the bottom of first opening. A screw press of any sorts can be placed or fixed directly under the first opening or if a transport device, like ex. a screw conveyor is placed under the vertical container (-s), where said the screw press is arranged at said first opening of the independently controlled transport screw, who acts related to inlet amount from one, two or several containers. The independent screw press can be any sorts of screw press, producing a second retentate and said a second filtrate; The invention further describes a method for separating slurry using a separator.

Description

DK 202100075 U3 1 Vertical or tangentially vibrating vertical separator Scope of the invention The present invention relates to a vertical or tangentially vibrating vertical separator (= vibrating vertical container) for separating solids from a slurry and a method for separating solids from a slurry.

Background of the Invention Separation of particles from a liquid is desirable in many cases, e.g. for recycling purposes or for more efficient handling or treatment of the separated components. An example could be the removal of solids from slurry (livestock manure) or similar organic sludge from a treatment plant for public waste water.

Separation of solids from liquid is important when using animal waste products such as manure. The slurry can be used in biogas plants for the production of ex biogas. However, it is important that the amount of dry matter in the slurry or in the proportion of slurry used in the biogas plant is as high as possible in order to be usable in terms of energy.

WO 96/30102 A1 describes a dewatering device in which a filter screen surrounds a screw press. The screw press provides a back pressure to the screw press with a flap lid in the outlet of the screw press because the lid has a weight mounted thereon. The filter screen is stationary when the unit is filled with the liquid to be filtered and remains stationary while a filter cake builds up at the bottom of the cylindrical filter screen. When the liquid level reaches a certain level in the unit, the filter screen is rotated, the filter cake is detached from the screen and falls into the inlet of the screw press. The filter cake is loosened by heavy water jets that act against the outer surface of the filter screen in the area above the inlet to the screw press.

US 6,227,379 describes a method and apparatus for removing solids from a slurry. The slurry is fed into a rotating container. As the vessel rotates, lift vanes lift some of the slurry so that the liquid portion of the slurry can fall back into the slurry pool to be separated and lift the solids towards the top of the vessel where the solids slide by gravity into a collection tray for transport out of the vessel.

DK 202100075 U3 2 The separation process as described in US 6 227 379 separates solids from liquid substances by gravity alone. Therefore, the solid fraction still contains a large amount of liquid, since a significant amount of liquid will be retained by the fibers in the solid fraction.

Purpose of the invention The purpose of the present invention is to achieve an improved method for separating slurries/slurries, where the solids and the liquid part of the slurry are separated more efficiently.

Description of the invention The aim is achieved by providing a separator according to claim 1 for separating solids from a slurry.

By "slurry" is meant any kind of liquid including solids, but preferably animal manure and waste water. More preferred are animal manure and waste water with a particle size of over 50 µm.

By "filtrate" is meant what is drained from the slurry or from any of the retentates during the separation process. Filtrate can be referred to as the first, second or third filtrate.

"At least a first filtrate" means that more than the first filtrate may be present, ie. the first and second filtrate may be present, or the first, second and third filtrate may be present, etc.

By "retentate" is to be understood what remains of the slurry when the filtrate has been emptied. Retentate can be a mixture of the first and second retentate, the first, second and third retentate.

The vertically or tangentially vibrating vertical container comprises a side wall and two open ends and is preferably cylindrical in shape. As an alternative embodiment may

DK 202100075 U3 3 the container has a cross-section that is essentially parallel with at least one of the ends being a triangle, a square, a rectangle, a pentagon, a hexagon, etc. A cylinder has a basic curvilinear geometric shape, whose surface is formed by the points at a fixed distance from a given line segment, the axis of the cylinder. The solid enclosed by this surface and by two planes perpendicular to the axis is also called a cylinder. In this way, a cylinder can have any suitable cross-sectional shape perpendicular to its axis, such as circular, oval, triangular, rectangular, square, etc. The vibrating vertical container is connected to a support in a way that allows the container to be able to vibrate vertically or tangentially along its axis. In a preferred embodiment, the vibrating vertical container is attached to the support through vibration dampers. In this way, the oscillations of the vibrating vertical container are not transmitted to the support. The vibration dampers can e.g. be rubber or steel springs. The container is equipped with at least one asynchronous vibrating motor. Hereby, the container is able to swing back and forth in either the axial or the tangential direction of the vertical container. Thus, the filter cloth and/or the at least one secondary opening of the vertical container can be cleaned mechanically. Therefore, the separation process is not disturbed by coagulation on the filter cloth and/or the at least one opening. In one embodiment, the at least one asynchronous vibrating motor is mounted at one of the ends of the side wall of the vertical container.

In a further embodiment, the asynchronous vibrating motors are mounted at both ends of the side wall of the vertical container. The same number of asynchronous vibrating motors are mounted at each end of the side walls of the vertical container. By controlling the synchronous vibrations, it is possible to give the container vibrations with a relatively large amplitude, thereby exerting a significant influence on the materials inside the vibrating vertical container, resulting in an increase in separation, both

DK 202100075 U3 4 with regard to reducing the process time in the container and with regard to handling more material through improved separation.

The vibrating vertical container includes at least one first opening.

Through the first opening, the solids obtained from the slurry are removed from the vibrating vertical container.

Although the first opening is usually at the bottom of the vibrating vertical vessel, another possibility is that an axially placed tube is attached around and above the first opening and the first retentate enters this tube via an overflow at the top, because an aeration / flotation of the incoming sludge leads/forces solids content to go up.

The vibrating vertical container includes at least one second/secondary opening.

By this it is to be understood that one, two, three, four, five, six etc. secondary openings are provided in the vibrating container.

In a preferred embodiment, many secondary openings are provided in the vibrating container.

The at least one secondary opening will be provided in the side wall.

In one embodiment, a plurality of secondary openings are provided in the side wall.

The at least one secondary opening in the vibrating vertical container drains liquid in the form of a first filtrate from the slurry and leaves solids in the form of a first retentate in the vibrating vertical container.

In one embodiment, the size of the at least one secondary opening is equal to or less than 40 µm.

In one embodiment, the vibrating vertical container is provided with a filter cloth.

The filter fabric can be an edge filter or a cross-woven filter.

Providing the vibrating vertical container with a filter cloth increases the separation process.

Furthermore, smaller particles can be separated from the liquid part of the slurry using a filter cloth.

The vibrating vertical container is placed in a liquid/watertight container so that the first outlet of the first filtrate can be controlled by an automatically adjustable valve or a pump on

DK 202100075 U3 a way so that the level of the first filtrate can be adjusted in relation to the sludge level inside the vibrating container. In this way it is possible to find / optimize flow capacity related to TMP (Trans Membrane Pressure) above the filter and keep it optimized. 5 If there is only one vibrating vertical container, any type of screw press can be placed directly under the first opening of the vibrating vertical container. The screw press presses (squeezes) the first retentate obtained from the filtration, whereby additional liquid in the form of a second filtrate is removed from the first retentate. This increases the proportion of dry matter in the first retentate, which leaves a second/secondary retentate. If more than one vibrating vertical container - or other conditions such as indoor heights at the location are relevant - a transport device, such as a conveyor auger, can be placed directly under the first opening of the vibrating vertical container, and if several vibrating vertical containers are placed in parallel, several first openings add first retentate to the transport screw. This first retentate can be fed to the inlet of a screw press or other types of press devices. In a further advantageous embodiment, said where more than one vibrating vertical container is part of the overall installation, the discharge of the first retentate from each single container will occur at time and quantity intervals that are related to the inlet quantity, registered by a flow meter at the first inlet of each container and by opening an ex. gate valve located at the first opening, for a desired time related to a calculated volume. At any opening of the retentate valves, the transport unit will be active.

In a further advantageous embodiment, the separator also comprises a filtrate container for collecting at least the first filtrate; wherein the filtrate container is piped to the first outlet for the first filtrate. In this way, at least the filtrate can be collected and thereby prevented that at least the filtrate is simply poured onto the ground. In addition, the filtrate collected in the filtrate container can be used for cleaning the filter cloth/fabric on the vibrating vertical container.

DK 202100075 U3 6 In a further advantageous embodiment, the filtrate container is piped to a hydrocyclone. In an even more advantageous embodiment, a piped hydrocyclone is located above the first inlet to the vertical container.

A hydrocyclone is capable of separating very small solid particles from liquids and is thus capable of separating small solid particles from at least the first filtrate, resulting in a third retentate and a third filtrate. In this way, a larger amount of dry matter can be cleaned from the slurry. The third retentate from the hydrocyclone may contain elevated concentrations of phosphorus.

In one embodiment, dry matter particles down to less than 10 µm can be separated from the filtrate using the hydrocyclone. A hydrocyclone is a device for classifying, separating or sorting particles in a liquid suspension based on the ratio of their centripetal force to liquid resistance. A hydrocyclone will normally have a cylindrical section at the top, where liquid is fed tangentially, and a conical base. The angle and thus the length of the conical section plays a role in determining operating characteristics. A hydrocyclone has two exits on the axis: the smaller one at the bottom (reject) and a larger one at the top (overflow). The reject is generally the heavier or coarser fraction, while the overflow is the lighter or finer fraction. The third retentate from the hydrocyclone can either be fed to the conveyor screw to be mixed with the first retentate through a second inlet. In this way, larger solids in the first retentate will retain the smaller solids from the third retentate. Alternatively, the third retentate can either be fed to the second retentate, be returned to the pre-tank with the raw medium/sludge, be mixed with the raw medium at the first inlet, or alternatively the third retentate can be stored separately. In an advantageous embodiment, a pressure transmitter is mounted on the pipeline after the feed pump, and adjusts the pump's pressure here to ensure that the vibrating container is full of sludge. If desired, the pressure transmitter and feed pump can force a TMP, such that the first filtrate level in the watertight container is full, yet has a

DK 202100075 U3 7 certain TMP higher than zero Atm. Similarly, the pressure transmitter prevents an excessively high TMP, which can damage the filter cloth. Furthermore, a flow meter is located after the feed pump and just before each inlet to the vibrating vertical container(s). This both to monitor whether the filter fabric must be cleaned using the flushing system, to be able to calculate when the first opening must open to extract a desired volume of first retentate (if interval calculation) and to check whether the inlet velocity suddenly rises above a predetermined value, which may indicate that the filter fabric has broken/damaged. The current flow can either stop the entire installation, or if more than one vertical container, close the first inlet to the current container. In this way, the amount of sludge pumped into the vibrating vertical container(s) can be controlled and regulated to achieve the desired separation goals.

A CIP procedure can be performed with e.g. an acid. Before the procedure starts, the vibrating vertical vessel is emptied and the first retentate is removed from the separator by closing the inlet valve at the first inlet to the vibrating vertical vessel, but maintaining the separation process for a while until all retentate is removed from the vibrating vertical container. Then, usually after the vibration motors have stopped, a predetermined dose of acid is added in-line to the filtrate which is pumped into the flushing nozzles that clean the filter fabric in the watertight container. The vibrating vertical container is then washed down with the acidified filtrate. The washing down/cleaning can be carried out one or more times.

In an extended set-up, another CIP pump can be offered together with a chemical tank for dosing a base to the filtrate. In this way, the vibrating vertical container can be cleaned with both acid and/or base depending on the sludge/slurry to be separated.

DK 202100075 U3 8 Description of the drawing Fig. 1 illustrates a first embodiment of a single vibrating vertical separator where a sedimentation process occurs over a screw press; Fig. 2 illustrates a first embodiment of a single vibrating vertical separator where a flotation process occurs over a screw press; Fig. 3 illustrates an assembly of several vibrating vertical containers in which a sedimentation process takes place together with a transport screw and a conventional screw press; Fig. 4 illustrates a three-dimensional view of a similar embodiment of a separator; Fig. 5 illustrates a cross section of a similar embodiment of a separator.

Detailed description of the invention Fig. 1, 2 and 3 illustrate a first design for a vibrating vertical separator 100, where Fig. 1 illustrates the separator, where the slurry is pumped by the feed pump 25 at a pressure determined by pressure transmitter 26, through flow meter 27 and inlet valve 28 to the first inlet 7 in the vibrating vertical filter column 1, where first retentate 40 is sedimented under a closed center tube 15 down to the first opening 8 and from there directly down to a screw press 34 through an automatic on/off slide valve 16 (optional equipment).

Fig. 2 shows the separator with the same inlet through the flow meter 27, but the inlet is mixed here, by means of the injector valve 29, with the air-enriched and air-saturated recirculated first filtrate 41, to create a flotation in the vibrating vertical filter column 1, which is why the first retentate 40 from the raw slurry via overflow, runs down into an axially located and to the outlet 8 attached pipe, which is mounted directly on 8 through valve 16 (optional equipment) to the screw press 34.

Fig. 3 illustrates a multiple of first vertical separators 100a, 100b, 100c, ... with vibrating vertical containers 1a, 1b, 1c. … with sedimentation of first retentate 40a, 40b, 40c, … down through first opening 8a, 8b, 8c, .… and further through valves 16a, 16b, 16c,.… for first retentate connected to a common transport auger connected to a common screw press.

DK 202100075 U3 9 Overall, the vibrating vertical container / separator can, for example, separate 3,000 liters of raw manure per hour, i.e. here animal waste. The slurry is pumped from ex. a pre-tank with a submersible pump 25 in a pressure 26 and flow-determined 27 pipeline to a vibrating vertical container 1 through an open on/off slide valve 28.

The vibrating vertical container 1 is surrounded by a waterproof container 10, where between the two components there is an elastic membrane 3 of e.g. NBR, attached to make it waterproof. The actual vibrating vertical container 1 is e.g. made from a mixture of glass and carbon fiber and resin, which is why the weight is 80% lower than if it is made of stainless steel and the power consumption in the vibration motors 6a and 6b is reduced accordingly. The first opening 8 is a hopper attached to the transport device 31 or the screw press 34 with an automatic on/off slide valve 16 in between and here a similar NBR membrane 3 is the connection between the vibrating container and the fixed hopper.

The bottom of the liquid-tight container 10 is placed with an outlet 11 for draining the first filtrate 41 from the container 10.

Two asynchronous vibration motors 6a and 6b are mounted at the lower end of the side wall 2 of the vibrating container 1. The asynchronous vibration motors 6a, 6b cause the vertical container 1 to perform reciprocating movements (e.g. + /- 4 mm) in the axial or tangential direction of the vertical container 1. This gives the same advantages as an improved mechanical cleaning of the filter cloth, in a traditional horizontal vibrating screen.

Although not illustrated, an alternative embodiment has an arrangement of two synchronously vibrating motors located at the top of the vibrating vertical container side wall 2. Of course, there may be more asynchronous motors located on the container as long as they are arranged symmetrically with respect to .the axis of rotation.

The bottom of the side wall 2 of the vertical container 1 is mounted on the vibration dampers 4x fixed on some legs, e.g. as a square tube attached to the floor 5, to prevent vibrations from being transmitted from the vibrating container 1 to the support 5.

DK 202100075 U3 10 The slurry is fed into the vertical container 1 through a first inlet 7. The first retentate 40 is pressed by gravity through an automatic on/off slide valve 16 to either a transport device 31 if more than one vibrating vertical container 1, or directly into the screw press 34, where the first retentate 40 is pressed/squeezed so that there is a drain of second filtrate 43 through holes 35 in the screw press 34. During this pressing, the material is pressed against a resisting plate, disc or pneumatically forced piston or a back pressure screw 38, which provides resistance from a motor or as a spring 37, and a plug is built up which forms the block against which the pressure in the screw press 34 presses the second filtrate 43 out of the material, producing a second retentate 42. The separation process of the first retentate 40 into a second retentate 42 and a second filtrate 43 is adjusted and driven by a frequency-controlled and torque-registering motor 33.

The vibrating vertical filter column 1 is placed in a watertight container 10 so that the first outlet of the first filtrate 41 can be controlled by an automatically adjustable valve 12 or a pump (not shown) in such a way that the level of the first filtrate 41, measured by level transmitter 14 can be adjusted in relation to the sludge level inside the vibrating container, observed by level transmitter 13. In this way it is possible to find / optimize flow capacity related to TMP above the filter and keep it optimized. In an advantageous design, a pressure transmitter 26 is added to the pipeline after the speed-regulated feed pump 25 to adjust the pressure exerted by the pump 25 to ensure that the vibrating filter column 1 is full of sludge. If really desired, the pressure transmitter 26 and the feed pump 25 can force an additional TMP option so that the first filtrate 41, at level 14 in the watertight container 10 is full and still has a certain TMP higher than zero Atm. In the same way, the pressure transmitter 26 prevents too high TMP that can damage the filter cloth 9.

The first filtrate 41 is collected next to the vibrating vertical container 1 in a filtrate tank 39 with a level transmitter 24. The first filtrate 41 can be pumped using the filtrate pump 17 through a hydrocyclone 21. In the hydrocyclone 21, small solids can substances

DK 202100075 U3 11 is removed from the filtrate, resulting in a third retentate 44 and a third filtrate 45. The third retentate 44 can be directed to the first inlet 7 to be mixed with raw slurry, mixed with the first retentate 40 before the screw press , is mixed with the second retentate 42 after the screw press 34, returned to the pre-tank or (not shown) collected in the tank for only the third retentate 44, if the content has special value.

The first filtrate 41 can be used for additional cleaning of the filter cloth 9, using pump 17 through the open valve 18 to a set of nozzles 19, which are placed on either a vertical tube that is moved around the filter cloth or a tube that is mounted around the vibrating vertical filter 1 and which is moved up and down along the filter cloth 9 by a motor 20. This cleaning can be controlled in relation to the flow capacity, registered by the flow meter 27, located before the first inlet 7 of each vertical container or related to cleaning after emptying container 100. If more than one vertical container 100, they can all be cleaned individually, in parallel with two or more 100s at the same time and everything is controlled by the PLC controller.

Before the whole installation is stopped if there is no more sludge/slurry to process (low level in the pre-tank indicated by 23) or if more than one vertical container 100 is installed and active and one of these vertical containers 100 signals e.g. a very high flow rate, as well as if the filter fabric is damaged, the emptying procedure begins by emptying either all containers or just the one for service, by closing the inlet valve 28, so that the inlet of sludge into the vibrating vertical filter column 1 is closed, but the separation of sludge is maintained in the current container by reducing the level of first filtrate 41 and in this way keeping the same TMP until a defined level is reached for the first retentate 40 and then the remainder of the first retentate 40 is drained out of the open valve 16 and active transport device 31 and or the screw press 34 until the level transmitter 13 indicates that the vibrating vertical filtration column 1 is empty.

The vibration motors 6a, 6b are stopped, and then the transport device/screw 31 and/or the screw press 34 can be stopped.

A CIP procedure can be performed using either an acid or a base.

DK 202100075 U3 12 Using the CIP pumps 46 or 47, a predetermined dose of acid or base is added in-line to the filtrate from a chemical tank (not shown). The vibrating vertical vessel 1 is then rinsed down with the acidified/basic filtrate.

The washing down/rinsing can be carried out one or more times before restarting the separation.

DK 202100075 U3 13 Parameter

1. Vibrating vertical filter column 30. Motor: Transport screw!

2. Side wall 31. Transport auger

3. End walls 32. Retentate (sludge) mixture -

4. Vibration damper inlet Screw press

5. Fixed base 33. Motor screw press Ba. M2.01a (Vibration motor) 2 Pressure auger dead Filtrate 6b. M2.01b (- do -) 36. Outlet secondary Filtrate

7. First Inlet 37. Engine for back pressure snow or

8. First opening for first Retentate pneumatic back pressure disc

9. Second opening for first Filtrate 38. Back pressure auger! or disc

10. Liquid-tight container 39. Small buffer tank for first Filtrate

11. Expiry for first filtrate

12. AV2. 01: Analog control valve 40. First Retentate

13. LT2.0%: Level transmitter 41. First Filtrate

14. LT2.02: Level transmitter 42. Other Retentate

15. Internal, axially centered closed 43. Second Filtrate container tube 44. Third Retentate

16. V2.02: Abenflukke valve 45. Third Filtrate

17. P2.01: Pump 46. Acid pump

18. V2.01: Open/close valve A7. Base/lye pump

19. Spray nozzles

20. M2.02: Motor

21. Hydro cyclone

22. PT2.03: Pressure transmitter

23. LT1.01: Level transmitter

24. LT2.03: Level transmitter

25. P1.01: Feeding pump

26. PT1.01: Pressure transmitter

27.FT1.01: Flow transmitter

28. V1.01: Open/close valve

29. V1.02: Open/close valve

Claims (5)

DK 202100075 U3 14 REQUIREMENTS 1. A separator for separating dry matter from a sludge mixture / e.g. slurry comprising - a vertical or tangentially vibrating vertical container (1) consisting of a side wall (2) and two open end walls, flexibly connected to said surroundings (3) where said vibrating vertical container (1) is fixed using a number of vibration dampers (4x) on said support (5); - and furthermore, the vertically or tangentially vibrating vertical container is provided with one, two or more asynchronous vibration motors (6a-6x), mounted on the bottom, on the top or a mixture of the same on the vibrating container (1), which produces the vertical or tangential vibrations in the vertical container; - and further, the vertically or tangentially vibrating vertical container is provided with at least one first inlet (7) for the sludge and at least one guided opening (8) for the first dewatered retentate (40), - and furthermore the vertically or tangentially vibrating vertical container comprises there (1) at least one second opening (9) for the first filtrate (41); - which is placed inside a waterproof container (10), in which the level of first filtrate can be checked and level-regulated by an automatic analogue control valve (12) or by means of e.g. a pump, located after an outlet (11) on the watertight container (10); - since the level in the watertight container (10) is detected using one level sensor (13) inside the vertically or tangentially vibrating vertical container (1) and another level sensor (14) inside the watertight container (10), TMT (Trans -Membrane-Pressure) above the side wall (2) is registered and controlled by an analogue outlet through e.g. the analog control valve (12); - and furthermore is a transport device (30), which e.g. a transport auger (31), located below the first opening (8) and if further vertically or tangentially vibrating vertical containers (1a, 1b, 1c,..), then further to the first opening (8x) of another or a further number of the first openings (8) of parallel vertically or tangentially vibrating containers, the first retentate is transported to the outlet (32), - which, if sedimentation is the purpose of the separation, then an additional closed vertical container (15) is placed to reduce the sludge volume within the DK 202100075 U3 15 (1) and thus reduce the distance between the internal sludge and the side wall (1), which increases the downward flow rate of the first retentate (40) down the filter surface (1) using gravity; - or, if flotation is the purpose of the separation, an open vertical container (15a) is additionally placed inside connected to/functioning as the first opening (8), which reduces the sludge volume inside (1) and thus reduces the distance between the internal sludge and the side wall (1), which using aeration/flotation with e.g. air-enriched first filtrate through an air injector on/off valve (29) which will increase the flow rate upwards along the filter surface (1); - and if further separation is necessary, with e.g. a screw press (33, 34) at the end of e.g. a transport auger (31), where said first retentate (40) is pressed using (33, 34) against an electrically or pneumatically (37) regulated back pressure screw or disk (38) to produce a secondary retentate (42) and drain away of a secondary filtrate (43) through said at least one hole (35) in said outlet (36) wherein said secondary filtrate (43) can be returned to said sludge tank (50); - or if the plant can consist of one vertically or tangentially vibrating container, any type of screw press (33, 34, 37, 38) can be similar to the specified transport device (30, 31). 2. The separator according to any one of the preceding claims, characterized in that an automatic open/close valve (16) located after the first opening (8) can be controlled to adjust the amount of first retentate (40) that leaves each vertically or tangentially vibrating vertical containers (1), by natural gravity. 3. The separator according to any one of the preceding claims, characterized in that the transport device/screw (30) and the screw press (33) can be speed regulated and start/stop activated, depending on the amount of the first retentate (40). 4. The separator according to any one of the preceding claims, characterized in that the first filtrate (41) can by means of pump (17) through valve (18) be used to clean DK 202100075 U3 16 the side wall (1) by backwash nozzles (19) which are moved axially/vertically or tangentially (around) the side wall (2) with Motor (20). 5. The separator according to any one of the preceding claims, characterized in that the first filtrate (41) is piped downstream to a hydro-cyclone (21).