DE102022127838A1 - Sewage sludge filter with mechanical cleaning and an integrated mechanical discharge system - Google Patents

Abstract

The invention relates to a cleaning device for removing solids from a liquid, in particular sewage sludge. It is therefore an object of the invention to eliminate the disadvantages of the prior art and to provide a cleaning device or a filtration system and a method by means of which / which the Filtration fineness of sewage sludge is significantly improved. This object is achieved by the features listed in the claims.

Description

The invention relates to a cleaning device for removing solids from a liquid, in particular sewage sludge.

In most sewage treatment plants there is a pre-cleaning system in the sewage sludge inlet for further treatment, consisting of a rake and/or a filter sieve to remove coarse components from the sewage sludge depending on the mesh size of the rake and the pre-filtration.

Despite the installation of this pre-cleaning stage, the sewage sludge contains non-organic substances and impurities up to microfibers made of polyester and microplastic components.

Presentation of the invention

It is therefore the object of the invention to eliminate the disadvantages of the prior art and to provide a cleaning device or a filtration system and a method by means of which the filtration fineness of the sewage sludge is significantly improved.

This problem is solved by the features listed in the claims.

• Einen Filterkörper, welcher geneigt oder horizontal mit einem Anstiegswinkel φ gelagert ist und welcher hohlzylindrisch mit zwei Enden ausgestaltet ist. Im Filterkörper ist zumindest ein Filterelement angeordnet, wobei das zumindest eine Filterelement an dem Ende des Filterkörpers angeordnet ist, welches am tiefsten Punkt des Filterkörpers gelegen ist. Eine tiefer gelegenes Ende des Filterkörpers entsteht durch die geneigte Lagerung des hohlzylindrischen Filterkörpers. Ferner weist die Reinigungsvorrichtung eine erste Antriebseinheit auf, welche derart mit dem Filterelement im Filterkörper verbunden ist, dass diese erste Antriebseinheit eine Drehbewegung des Filterelementes um seine vertikale Achse ausführt. Bevorzugt handelt es sich bei dieser Drehbewegung um eine 360°-Drehbewegung des Filterelementes um seine vertikale Achse. Ferner weist die Reinigungsvorrichtung eine Austragseinrichtung auf. Diese Austragseinrichtung weist gemäß verschiedener Ausführungsformen eine Spiralförderschnecke, eine zweite Antriebseinheit und eine Presskammer mit einer Pressschnecke auf. Die Spiralförderschnecke ist im Filterkörper und außerhalb des Filterelementes derart angeordnet ist, dass bei einem Filtrierungsprozess einer fluiden Masse, beispielsweise Klärschlamm, ein sich auf dem Filterelement aufbauender Filterkuchen mit der Spiralförderschnecke in die Presskammer zur Pressschnecke abtransportiert wird. (Als Filterkuchen wird der Rückstand aus zurückgehaltenen Stoffen bezeichnet, der sich bei der Filtration auf der Oberfläche eines Filterelementes bildet.) Hierfür wird die Spiralförderschnecke gemäß verschiedener Ausführungsformen mittels einer zweiten Antriebseinheit, unabhängig zum Filterelement, beispielsweise in entgegengesetzte Richtung zum Filterelement, angetrieben. Die Pressschnecke in der Presskammer presst den abgetrennten und transportierten Filterkuchen und transportiert diesen zur Austrittsöffnung.

According to various embodiments, the cleaning device according to the invention for removing solids from a liquid, in particular sewage sludge, has the following components:

• A filter body which is mounted inclined or horizontally with an angle of rise φ and which is designed as a hollow cylinder with two ends. At least one filter element is arranged in the filter body, the at least one filter element being arranged at the end of the filter body which is located at the lowest point of the filter body. A lower end of the filter body is created by the inclined mounting of the hollow-cylindrical filter body. Furthermore, the cleaning device has a first drive unit, which is connected to the filter element in the filter body in such a way that this first drive unit rotates the filter element about its vertical axis. This rotary movement is preferably a 360° rotary movement of the filter element about its vertical axis. Furthermore, the cleaning device has a discharge device. According to various embodiments, this discharge device has a spiral conveyor screw, a second drive unit and a pressing chamber with a pressing screw. The spiral conveyor screw is arranged in the filter body and outside of the filter element in such a way that during a filtration process of a fluid mass, for example sewage sludge, a filter cake that builds up on the filter element is transported away with the spiral conveyor screw into the press chamber to the press screw. (The residue from retained substances that forms on the surface of a filter element during filtration is referred to as filter cake.) For this purpose, according to various embodiments, the spiral conveyor screw is driven by a second drive unit, independently of the filter element, for example in the opposite direction to the filter element. The press screw in the press chamber presses the separated and transported filter cake and transports it to the outlet opening.

According to various exemplary embodiments, the squeezing screw is driven together with the spiral conveyor screw by means of the second electric motor.

Furthermore, according to various exemplary embodiments, the cleaning device has at least one wear strip, which stabilizes the press screw and/or the spiral conveyor screw.

According to various exemplary embodiments, the angle of rise Phi φ, by which the hollow-cylindrical filter body is mounted at an angle, is acute. The angle Phi φ is preferably in a range from 1° to 50°. The angle of inclination Phi φ is particularly preferably in a range between 10 and 35°. The angle of inclination Phi φ is particularly preferably 25°.

Furthermore, the filter element has a stripping element, which is arranged inside the filter body in such a way that during the vertical rotary movement of the filter element, a filter cake that builds up on the filter element is separated and discharged into the filter body. Two stripping elements are preferably arranged opposite one another on the filter element.

Spiral conveyor screw and press screw each have a screw thread, with the screw thread of the press screw preferably running in the opposite direction to the spiral screw according to various exemplary embodiments.

Furthermore, the press chamber preferably has a closure side which is rear-ventilated, so that sticking/pressing of the filter cake at the end of the press chamber or at the end of the cleaning device is prevented.

The press screw preferably has a discharge blade, which in turn is preferably arranged in the area of the outlet opening. The discharge shovel ensures that the separated and pressed filter cake is guided to the outlet opening.

According to various exemplary embodiments, the cleaning device also has a bypass line, which is arranged at the outlet opening and/or at the pressing chamber in such a way that any residual moisture liquid present there is fed back into the filter body. For this purpose, the bypass line is preferably arranged at a lowest point in front of the outlet opening and at the end of the filter body which is located at the lowest point of the filter body. By means of this arrangement, the separated organics and liquid can flow back from the press chamber into the filter housing via the rise angle Phi <p, for example 25 degrees.

When the filter cake is sufficiently pressed in the press chamber and when the filling level is reached, the outlet opening opens and the filter cake is automatically transported out of the cleaning system by means of the press screw and/or the discharge shovel. A slide is preferably arranged at the outlet opening, which slide opens automatically when enough filter cake is pressed against the outlet opening and/or the slide.

A desired dry substance value of the filter cake, from which the filter cake should be ejected from the cleaning device, can preferably be set. For this purpose, according to various embodiments, the cleaning device preferably has a control unit and/or a regulating unit and/or a sensor unit. For example, the dry substance value can be determined by means of a sensor unit. By means of a control unit, for example, the outlet opening can be opened automatically. By means of the control unit, for example, the cleaning device can be controlled using preset and/or actual values.

According to various embodiments, the cleaning device also has spray nozzles for cleaning the filter element, the spiral conveyor screw and/or the press screw. The spray nozzles are preferably water cleaning nozzles which have a connection, for example to a water supply and/or to a water reservoir and/or to a cleaning liquid.

Furthermore, the cleaning device has an inlet opening, via which the pre-cleaned sewage sludge is fed to the filter system/cleaning system, for example by means of a sewage sludge feed pump. A pressure relief valve is attached to the inlet of the filter system to avoid excessive pressure. In the front area of the filter body, which is arranged in a horizontal version with a rise angle φ of preferably approx. 25 degrees, there is a filter element which performs a 360 degree rotary movement via an electric motor (the filter element is preferably used here as a split-edge filter with the option of use of different filter fineness). Opposite scrapers are installed on the filter outer diameter. These mechanical scrapers are preferably spring loaded and adjustable. A scraper is divided into segments along its longitudinal axis and has sharp edges. Due to the 360 degree rotation of the filter element, the filter cake that builds up on the filter element is separated and discharged into the filter housing of the filter body. This separated filter cake contains all non-organic components and impurities, including microfiber and microplastic particles. A spiral conveyor screw is arranged around the entire filter element with mechanical cleaning. This spiral conveyor screw is preferably driven by an electric motor that is installed at the outlet of the filter element, independently of the filter element and also has a 360 degree rotary movement. The filter element and/or the spiral conveyor screw or the press screw can be cleaned using spray nozzles. The spiral conveyor screw conveys the separated filter cake with all impurities into a press chamber. In this press chamber is the press screw, which is preferably also driven by the electric motor of the spiral conveyor screw, which is preferably connected to the press screw. To stabilize the filter, the press screw is preferably conically connected to the filter element via a bushing. Wear strips stabilize the augers from the beginning of the cleaning system to the discharge chute/discharge opening. The filter cake that has been separated and conveyed out of the filtration element is taken over by the press screw and pressed and compacted in the press chamber against an electrically driven slide (e.g. plate slide) at the outlet opening of the cleaning system. The press auger runs in opposite directions in the area of the press chamber and the closing side of the press chamber is rear-ventilated. This rear ventilation also applies to an ejection chute, which is arranged in front of the outlet opening. The ejection chute is preferably round. The counter-rotating press screw is equipped with a discharge shovel in the area of the ejection chute and conveys the filter cake into the ejection chute. The residual moisture that occurs there is removed via a bypass line installed at the lowest point of the ejection chute returned to the filter body. The bypass line is separated with a screen at the ends so that the filter cake does not clog the bypass line. The organic matter and liquid separated in this way can flow back from the press chamber into the filter body via the 25-degree rise angle. If the filter cake is sufficiently pressed (which can be adjusted to the dry substance value to be achieved) in the press chamber and when the filling quantity is reached, the knife gate valve at the outlet of the filter housing opens and the press screw automatically conveys the filter cake out of the filter system. The filtration process does not have to be interrupted while the filter cake is being discharged from the press chamber, but continues to run continuously. After the filter cake has been discharged, the knife gate valve closes and the filter cake is again pressed against the closed knife gate valve until the next discharge process. The discharged filter cake with all impurities can then be disposed of with a very good residual moisture content. The cleaned sewage sludge flows through the filter element into what is known as a clean room and is fed from this clean room to another dewatering process that usually takes place. If necessary, the pressure at the outlet of the clean room can be regulated with a pressure relief valve.

The object is also achieved by means of a method for removing solids from a liquid using a cleaning device according to claim 1.

1. a. Einleiten einer fluiden Masse bestehend aus Flüssigkeit und Feststoffen in eine Reinigungsvorrichtung, wobei die fluide Masse in ein Filterelement eines Filterkörpers eingeführt wird, wobei das Filterelement mittels einer ersten Antriebseinheit in eine vertikale Drehbewegung um sich selbst versetzt wird, wobei die vertikale Drehbewegung bevorzugt eine 360°-Drehbewegung ist und
2. b. Austragen eines Filterkuchens, welcher außenseitig des Filterelementes entsteht, mittels einer Austragseinrichtung, wobei die Austragseinrichtung eine Spiralförderschnecke aufweist, welche von einer zweiter Antriebseinheit ebenfalls in eine Drehbewegung versetzt wird und dadurch den Filterkuchen vom Filterelement in eine Presskammer mit einer Pressschnecke befördert, wobei die Pressschnecke den abgetrennten und transportierten Filterkuchen presst und zur Austrittsöffnung transportiert.

The process has the following process steps:

1. a. Introducing a fluid mass consisting of liquid and solids into a cleaning device, the fluid mass being introduced into a filter element of a filter body, the filter element being set into a vertical rotary motion about itself by means of a first drive unit, the vertical rotary motion preferably being 360° -Rotational movement is and
2. b. Discharge of a filter cake, which is produced on the outside of the filter element, by means of a discharge device, wherein the discharge device has a spiral conveyor screw, which is also set in rotation by a second drive unit and thereby conveys the filter cake from the filter element into a pressing chamber with a pressing screw, the pressing screw conveying the separated and transported filter cake and transported to the outlet opening.

According to various exemplary embodiments, a filter cake that builds up on the filter element is separated by means of at least one scraping element during the vertical rotary movement of the filter element and is discharged into the filter body.

Furthermore, according to various exemplary embodiments, a residual moisture liquid present in the filter cake at the outlet opening is fed back into the filter body by means of a bypass line, which is arranged at the outlet opening.

According to various embodiment variants, when the filter cake is sufficiently pressed in the press chamber and when the filling quantity is reached, the filter cake is conveyed out of an outlet opening of the cleaning device. A dry substance value to be achieved for the filter cake can preferably be set.

After the filter cake has been discharged, the discharge opening closes again and the filter cake is again pressed against the closed discharge opening until the next discharge process.

character list

• 1 eine Ausführungsvariante der erfindungsgemäßen Reinigungsvorrichtung im Längsschnitt

The invention is explained in more detail using an exemplary embodiment. For this shows

• 1 an embodiment of the cleaning device according to the invention in longitudinal section

In the description, reference is made to the accompanying drawings, in which is shown by way of illustration specific embodiments in which the assembly of the invention may be practiced. In this regard, directional terminology such as "up," "down," etc. is used with reference to the orientation of the described drawings. The directional terminology is used for purposes of illustration and is in no way limiting.

It is understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. It is understood that the features of the various exemplary embodiments described herein can be combined with one another unless specifically stated otherwise. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

Within the scope of this description, the terms "connected", "connected" and "coupled" are used to describe both a direct and an indirect connection (e.g. ohmic and/or electrically conductive, eg in an electrically conductive connection), a direct or indirect connection connection as well as a direct or indirect coupling.

In the figures, identical or similar elements are provided with identical reference symbols, insofar as this is appropriate.

In 1 a cleaning device 1 according to the invention is shown in longitudinal section. The cleaning device 1 for removing solids from a liquid, in particular sewage sludge, has the following components:

The cleaning device 1 has a hollow-cylindrical filter body 2 with two ends, the filter body 2 being mounted inclined at a rise angle φ. According to various exemplary embodiments, the filter body 2 has at least one filter element 22, the at least one filter element 22 being arranged inside the filter body 2 and at the end of the filter body 2 which is located at the lowest point of the filter body 2. A first drive unit 3 is arranged on the filter element 22 in such a way that the at least one filter element 22 rotates about its vertical axis.

Furthermore, the cleaning device 1 has a discharge device 5 . According to various embodiments, the discharge device has at least one spiral conveyor screw 51 , a second drive unit 52 and a pressing chamber 53 with a pressing screw 54 . The spiral conveyor screw 51 is arranged in the filter body 2 and outside of the filter element 22 in such a way that a filter cake building up on the filter element 22 is conveyed with the spiral conveyor screw 51 into the press chamber 53 . For this purpose, the spiral conveyor screw 51 is driven independently (for example in the opposite direction) to the filter element 22 by means of the second drive unit 52 . The press chamber 53 has a press screw 54 , the press screw 54 pressing the separated and transported filter cake and transporting it to the outlet opening 55 .

Preferred and as in 1 the pressing screw 54 is shown connected to the spiral conveyor screw 51 . Both screws are preferably driven by the second drive unit 52 .

At least one wear strip 4 is arranged in the filter body 2 to stabilize the press screw 54 and/or the spiral conveyor screw 51 . In the embodiment of 1 two wear strips 4 are arranged in the filter body 2. These can be arranged opposite one another or offset at a certain angle to one another. A use of several wear strips 4 is conceivable.

Furthermore, the press screw 54 is preferably conically connected to the filter element 21 via a bushing/centering bushing 9 in order to stabilize the filter.

According to various embodiments, the rise angle φ is acute. The angle φ is preferably an angle in a range from 1° to 35°. The angle of inclination φ is particularly preferably equal to 25°.

Furthermore, according to various embodiments, the filter element 22 of the cleaning device 1 has at least one scraper element 21, which is arranged inside the filter body 2 in such a way that during the vertical rotary movement of the filter element 22, a filter cake that builds up on the filter element 22 is separated and discharged into the filter body 2 . According to various embodiments, but not in 1 shown, two or more stripping elements 21 can also be arranged, which are arranged opposite one another, for example, or are arranged offset from one another at an angle.

According to various embodiments and as in 1 shown, the press screw 54 is designed to rotate in the opposite direction to the spiral screw 51 .

Furthermore, the pressing chamber 53 preferably has a closure side which is ventilated from behind.

Furthermore, the press screw 54 preferably and as in 1 shown a discharge blade 56, which is arranged in the area of the outlet opening 55.

According to various embodiments, the cleaning device 1 also has a bypass line 56 which is arranged at the outlet opening 55 and/or at the pressing chamber 53 in such a way that any residual moisture liquid present there is fed back into the filter body 22 . The bypass line 56 is preferred and as in 1 shown at a lowest point in front of the outlet opening 55 and arranged on the filter body 2, with the bypass line 56 preferably being arranged at the lowest point of the filter body 2, so that the organic material and liquid separated in the cleaning device 1 can flow through the rise angle φ, preferably from (p=25 degrees can run back from the press chamber into the filter housing/in the filter body 2. The bypass line 56 can also be at other points of the filter body 2/the Rei be arranged 1, but in such a way that liquid is returned from the outlet opening 55 back into the filter body 2 again. Sieves are preferably located at the ends of the bypass line 56 (inlet and outlet of the bypass line 56), so that the filter cake does not get into the bypass line 56 or clog it.

The cleaning device 1 preferably has a control unit and/or a regulating unit and/or a sensor unit (in 1 but not shown).

When the filter cake is sufficiently pressed (which can be adjusted to the dry substance value to be achieved) in the press chamber and when the filling quantity is reached, the outlet opening 55, for example a slide, opens and the press screw 54 automatically conveys the filter cake out of the cleaning device 1.

The cleaning device 1 according to the invention preferably has spray nozzles for cleaning the filter element 22, the spiral conveyor screw 51 and/or the press screw 53, as in 1 shown.

The sewage sludge or the pre-cleaned sewage sludge is introduced into the cleaning system 1 via an inlet 8 . A pressure relief valve is preferably arranged at the inlet 8 of the cleaning system 1 to avoid excessive pressure.

The cleaned sewage sludge flows via the filter element 22 into a clean room and then via an outlet 7 out of the cleaning system 1 for further processing, for example for further processing in a dewatering process that usually takes place. Any pressure that may prevail at the outlet 7 can be regulated, for example, via a pressure relief valve arranged there.

A cleaning of the filter element 22 is conceivable: For this purpose, the filter body 2 can be backwashed against the direction of filtration. This can be done, for example, via a flushing connection on the filtrate outlet nozzle/outlet 7.

A group of fittings 561 for draining residual moisture can be integrated into the bypass line 56 and is attached to the bypass line 56 via an additional T-piece, for example. Residual moisture 11 can be emptied into a storage container by switching the fittings group 561, for example by means of valves. A further switchover of the fittings group 561 can also be used to clean screens which, for example, are blocked at the end of the bypass line 56 by means of a compressed air blast with compressed air 10 . A bridging of non-organic components that can form on the flange of the ejection chute 5/55 due to compression can also be destroyed by means of a compressed air blast 10 and leads to improved filter cake discharge when the outlet opening is opened, for example by means of a slide. In 2 the cleaning device according to the invention is shown with an additional group of fittings 561 in a bypass line 56 .

As an alternative or in addition to the bypass line 56 and the group of fittings for draining residual moisture, a drainage device 551 can be integrated at the outlet opening 55 . This can be arranged, for example, between a flange of the ejection chute of the outlet opening 55 and a slide. A slotted screen 5510 with longitudinal rods is integrated into this dewatering device 551, via which residual liquid can be better discharged from the compressed filter cake with all impurities, given a larger filtration area. For this purpose, the residual moisture liquid collects in a drainage chamber 5511 and can be drained via a drainage nozzle. Due to the arrangement of the slotted screen 5510 with longitudinal bars, the axial gaps between the slotted bars are better cleaned during the filter cake discharge. Such a drainage device 551 is in 3 shown. For this purpose, the drainage device 551 is arranged at the outlet opening. A detailed representation of the drainage device 551 is in 4 shown.

The group of fittings 561 described above can also be connected here to the drainage device 551 independently of the bypass line 56 .

Reference List

1

cleaning device

2

filter body

21

scraper element

22

filter element

3

First drive unit

4

wear strips

5

discharge device

51

spiral auger

52

second drive unit

53

press chamber

54

press screw

55

Outlet opening (with or without slider)

551

drainage device

5510

wedge wire

5511

drainage chamber

5512

drainage socket

56

bypass line

561

Fitting group for residual moisture drainage

57

discharge shovel

6

cleaning nozzles

7

Outlet (with pressure relief valve and/or with flushing connection)

8th

inlet (with pressure relief valve)

9

bushing/centering bushing

10

compressed air

11

residual moisture

φ

Angle of inclination/angle of ascent

Claims (16)

Cleaning device (1) for removing solids from a liquid, in particular sewage sludge, having the following components: a. a filter body (2) which is mounted at an angle of inclination Phi and which is designed as a hollow cylinder with two ends, and which has at least one filter element (22), the at least one filter element (22) being located inside the filter body (2) and on is arranged at the end of the filter body (2) which is located at the lowest point of the filter body (2), b. A first drive unit (3), which is connected to the filter element (22) in such a way that the first drive unit (3) rotates the filter element (22) about its vertical axis, c. A discharge device (5), having a spiral conveyor screw (51), a second drive unit (52), a pressing chamber (53) with a pressing screw (54), the spiral conveyor screw (51) in the filter body (2) and outside the filter element (22) is arranged in such a way that a filter cake that builds up on the filter element (22) is transported into the press chamber (53) with the spiral conveyor screw (51), which is driven to the filter element (22) by means of the second drive unit (52), the press chamber (53) has a press screw (54). Cleaning device (1) according to claim 1 , characterized in that the press screw (54) is connected to the spiral conveyor screw (51) and the press screw (54) is driven together with the spiral conveyor screw (51) by means of the second drive unit (52). Cleaning device (1) according to claim 1 or 2 , further having at least one wear strip (4) which stabilizes the press screw (54) and/or the spiral conveyor screw (51). Cleaning device (1) according to one of Claims 1 until 3 , characterized in that the rise angle Phi φ is acute. Cleaning device (1) according to any one of claims 1 to 4, characterized in that the angle of rise Phi is equal to 25°. Cleaning device (1) according to one of Claims 1 until 5 , further having at least one stripping element (21), which is arranged inside the filter body (2) in such a way that during the vertical rotary movement of the filter element (22), a filter cake that builds up on the filter element (22) is separated and drained into the filter body (2). becomes. Cleaning device (1) according to claim 6 , characterized in that the two stripping elements (21) are arranged opposite one another. Cleaning device (1) according to one of the preceding claims, characterized in that the pressing screw (54) is designed to rotate in the opposite direction to the spiral screw (51). Cleaning device (1) according to one of the preceding claims, characterized in that the pressing chamber (53) has a closure side which is rear-ventilated. Cleaning device (1) according to one of the preceding claims, characterized in that the press screw (54) has a discharge blade (57) which is arranged in the area of the outlet opening (55). Cleaning device (1) according to one of the preceding claims, further comprising a bypass line (56) which is arranged at the outlet opening (55) and/or at the pressing chamber (53) in such a way that a residual moisture liquid prevailing there can flow into the filter body ( 22) is returned. Cleaning device (1) according to claim 11 , characterized in that the bypass line (56) is arranged at a lowest point in front of the outlet opening (55) and at the end of the filter body (2) which is located at the lowest point of the filter body (2). Cleaning device (1) according to any one of the preceding claims, further comprising a Control unit and / or a control unit and / or a sensor unit Cleaning device (1) according to one of the preceding claims, further comprising spray nozzles for cleaning the filter element (22), the spiral conveyor screw (51) and/or the press screw (53). Cleaning device (1) according to Claim 14 , characterized in that for cleaning the filter element (22) a rinsing connection is arranged at the outlet (7), so that the cleaning of the filter body takes place against the filtration direction by means of backwashing Cleaning device (1) according to claim 1 , characterized in that a drainage device (551) is arranged on the discharge device (5) and/or on the outlet opening (55) for residual moisture drainage and/or a fitting group (561) for residual moisture drainage is arranged in the bypass line (56). .

Images