Pile fabric filter

Abstract

The present invention relates to a water treatment system for pile fabric filtration, comprising at least one suction slot for backwashing, and a pile fabric filter having pile fibers fastened to a pile fabric support structure, wherein the pile fabric support structure has open, flow-relevant pores. According to the invention, the ratio of the slot area per suction bar to the area of the flow-relevant pores of the pile fabric support structure in the slot area per suction bar is between 1.1 and 9.5, preferably between 1.25 and 9, more preferably between 1.5 and 8.5, even more preferably between 2 and 8, even more preferably between 2.25 and 7.5, and particularly preferably between 2.5 and 7.

Description

[0001] DESCRIPTION

[0002] Polarizing filter

[0003] The present invention relates to a water treatment plant for pollutant filtration with at least one suction slot for backwashing.

[0004] Pile filtration is a mechanical process for separating organic and inorganic solids as well as surfactants from Newtonian and non-Newtonian fluids, particularly liquids and gases, preferably water, and especially wastewater. In the broadest sense, it belongs to the processes of surface filtration, cake filtration, or precoat filtration (with a fixed auxiliary agent), whereby, in addition to the sieving effect, true filtration effects occur along the depth of the pile fiber layer. Pile filtration is considered an outside-in filtration process in which raw water flows through the pile filter, removing solids that are retained both on the surface and within the pile fiber layer. Pile filtration represents an important subfield of cloth filtration and is used particularly for water and wastewater treatment.In polarity filtration, three-dimensional filter media, known as polarity materials, are used. The polarity filter is mounted, for example, on a disc (disc filter) consisting of individual segments, a drum (drum filter / pressure drum filter), a plate (plate filter), or a grid support with a diamond-shaped cross-section (diamond filter).

[0005] The known polarizing materials for polarizing filtration (polarizing filters) can be classified, among other things, by the height of the erected polarizing fibers (typically between 6 and 20 mm), the diameter of the individual filaments, the specific surface area of ​​the polarizing fibers, and the basis weight of the polarizing fabric. Current polarizing filters can be divided into three different categories based on their fiber diameter: standard, micro, and ultrafibers. Today, standard fibers with an equivalent fiber diameter > 10 pm, microfibers with an equivalent fiber diameter > 5 pm - < 10 pm, and ultrafibers with an equivalent fiber diameter < 5 pm are the most common polarizing filters used in water treatment for municipal and industrial applications.

[0006] The flow resistance of the filter material increases rapidly as the flow channels become clogged or blocked. The filter material must therefore be cleaned at regular intervals. This is usually done by backwashing, i.e., by passing a liquid, such as filtrate, through the filter material in the opposite direction to the flow direction. Backwashing can be performed simultaneously across the entire surface of the filter material or only on a section of the filter material, which is moved gradually across the surface. Backwashing can be carried out using a suction bar with suction slots formed by suction lips. During filter cleaning, the filter material or the layer of fibers moves past or above the suction bar at a speed of 1–1000 mm / s, and the suction bar can also move past or above the filter material.

[0007] The present invention is based on the objective of providing an optimized polarizing filter for water treatment, in particular for polarizing filtering.

[0008] The problem is solved in a water treatment plant with a filament filtration system, a suction slot for backwashing, and a filament with filament fibers attached to a filament support structure by providing the filament support structure with open, flow-relevant pores, wherein the ratio of slot area per suction bar to the area of ​​the flow-relevant pores of the filament support structure in the slot area per suction bar is between 1.1 and 9.5, preferably between 1.25 and 9, more preferably between 1.5 and 8.5, more preferably between 2 and 8, more preferably between 2.25 and 7.5, and particularly preferably between 2.5 and 7.

[0009] The pollen material is mounted, for example, either on a disc (disc filter) consisting of individual segments, a drum (drum filter / pressure drum filter), a plate (plate filter) or a grid support with a diamond-shaped cross-section (diamond filter).

[0010] During backwashing, flow-induced negative pressure forces fluid from the back of the filter material through the filter fiber layer, reversing the flow direction locally in the area of ​​the suction slot and fluidizing the filter fiber layer. This process can dislodge any solid particles adhering to the filter fiber layer from the flow channels. This can be achieved, for example, by suction using a filter cleaning pump. Backwashing can be performed with a suction bar featuring one or more suction slots. The filter material can be described by the following formula.

[0011] Ts = As / Ap

[0012] with

[0013] Ts: Ratio of slot area per suction bar and the area of ​​the flow-relevant pores of the polar material carrier structure in the slot area per suction bar

[0014] As = Slot area per suction bar

[0015] Ap = Area of ​​the flow-relevant pores of the polar material carrier structure in the slot area per suction bar

[0016] As is defined as the slot area per suction bar that is in direct contact with the pile material or the pile fiber layer during filter cleaning. The slot width is primarily determined by the filter area to be cleaned and is therefore dependent on the design of the pile material.

[0017] The pile support structure is a textile surface with large, flow-relevant and non-filter-active pores, serving as a support for the filter-active pile fiber layer. Flow-relevant pores are defined as the openings in the pile support structure that remain permeable to the fluid even in the event of incipient fouling and / or scaling. The pile fibers, for example, are not guided through the flow-relevant pores.

[0018] The pore area of ​​the individual flow-relevant pores (Ap) ore ) is, for example: A PO re s 0.30 mm 2 (for example, 0.5 mm wide and 0.6 mm long pore) or A Pore > 0.36 mm 2 (for example, 0.6 mm wide and 0.6 mm long pore) or A Pore > 0.64 mm 2(for example, 0.8 mm wide and 0.8 mm long pore). The flow-relevant pores do not need to be rectangular. The area of ​​the flow-relevant pores can be calculated, for example, by multiplying the number of flow-relevant pores per unit area by the pore area of ​​the corresponding pores. Both the number of flow-relevant pores and the pore area can be determined, for example, using imaging techniques. The area of ​​the flow-relevant pores of the polarizing material carrier structure can be determined in the slot area of ​​the suction bar. The flow-relevant pores of the polarizing material carrier structure must meet the aforementioned requirements in the slot area. The area of ​​the flow-relevant pores of the polarizing material carrier structure can be between 13.5% and 50%, preferably between 14% and 25%, and particularly preferably between 14.5% and 22% of the total area of ​​the polarizing material filter.

[0019] The polarizing filter and the polarizing material are described prior to use at time t = 0: Any scaling and / or fouling of the polarizing material support structure is not considered in this description. Scaling and / or fouling of the polarizing material support structure can negatively affect the size of the flow-relevant pores and be reduced in the effective flow-relevant area at time t = x. The area of ​​the flow-relevant pores and the total number of pores are determined by image analysis at time t = 0.

[0020] To determine the area of ​​flow-relevant pores, at least 10 individual pores in 5 material samples of the same specification must be measured and an average value calculated. The area of ​​the flow-relevant pores is determined in the functional state of the pile material, i.e., with the pile fibers connected to the pile support structure, and in the state of the pile material at time t = 0 before processing. A minimum area of ​​1 cm² is required to determine the number of flow-relevant pores. 2 The number of pores is measured in at least five samples of the same material specification, and an average value is determined. The number of pores is determined in the functional state of the filter material, i.e., with the fibers connected to the support fabric, and in the state of the material itself at time t = 0 before processing. The number of flow-relevant pores can, for example, range from 1 to 100 1 / cm². 2If pole and / or back fibers lie above the flow-relevant pores on the back side of the pole carrier structure or cross the pores (at time t=0 or at a time after a certain operating time), these pores are not to be counted as flow-relevant.

[0021] The flow-relevant pores can be arranged in a periodic pattern within the polar carrier structure, for example, as a checkerboard or line pattern. In a checkerboard pattern, flow-relevant and non-flow-relevant pores alternate in both horizontal rows and vertical columns. In a line pattern, vertical columns or horizontal rows of flow-relevant pores alternate with columns or rows of non-flow-relevant pores.

[0022] The pile fabric structure can be, for example, woven, nonwoven, knitted, or crocheted. A woven fabric is a textile fabric made of at least two yarn systems (warp or weft) that intersect at an angle of exactly or approximately 90° when viewed across the fabric surface. A knitted fabric is a textile fabric made of yarn systems produced by loop formation on a knitting machine. A knitted fabric is a fabric produced by knitting. While in knitting the entire row of stitches is created at once, in crochet the stitches are formed sequentially. A nonwoven fabric is a structure made of fibers of limited length, continuous fibers, or cut yarns that are combined and bonded together to form a fiber layer.

[0023] A pile fiber layer is a layer consisting of numerous individual pile fibers. These individual fibers (piles) are bundled into nubs (pile nubs) and connected to the pile support structure. The individual pile fibers can consist of single filaments or multiple filaments. Solids retention is determined solely by the pile fiber layer. The finer the fibers of the pile fiber layer, the higher the solids retention, meaning smaller particles can be separated.

[0024] The fibers within a single pimple and / or the fibers within different pimples can be different. In this context, "being different" preferably means the following:

[0025] • The fibers of at least one pollen nub can, for example, consist of different materials.

[0026] • It is also possible that the fibers of the at least one pollen nub have different equivalent diameters.

[0027] • The fibers of the at least one pollen nub can have different cross-sectional shapes.

[0028] • The fibers of at least one pollen nub can have different textures.

[0029] • Furthermore, it is also possible that the fibers of at least one pollen nub have different turbulences.

[0030] • Finally, the fibers of the at least one pollen nub may differ in their chemical and / or biological degradability.

[0031] Surprisingly, it has been found that, in addition to the height of the erect pole fibers, the diameter of the individual filaments, the specific surface area of ​​the pole fibers and the basis weight of the pole fabric, the size of the flow-relevant pores of the pole carrier structure has a significant influence on the pole filtration.

[0032] A defined sealing surface can be provided both before and after the extraction slot by means of an extraction lip or similar technical aids. The width of the sealing surface before and / or after the extraction slot, measured from the respective slot edge, can be > 5 mm, preferably > 8 mm, particularly preferably > 10 mm, particularly preferably > 12 mm, particularly preferably > 15 mm, further preferably > 20 mm, > 25 mm, > 30 mm, > 40 mm, > 50 mm, > 60 mm, > 70 mm, > 80 mm, > 90 mm and very preferably > 100 mm.

[0033] Especially when the pile fabric is not flat, adapting the extraction slot to the pile fabric support can prove advantageous. This is particularly beneficial for drum filters.

[0034] One embodiment of the invention consists in the slot width of the extraction slot being between 0.1 mm and 8 mm, preferably between 0.25 mm and 7 mm, more preferably between 0.5 mm and 6.5 mm, more preferably between 0.75 mm and 6 mm and particularly preferably between 1 mm and 5.5 mm.

[0035] In simplified terms, the slot length is determined by the area of ​​the pollen to be cleaned.

[0036] Typically, the slot length per suction bar ranges from 0.05 to 5.0 m, depending on the filter type and surface area of ​​the filament. The slot width depends on the filament material (filament fiber layer and filament fiber support structure), the design of the filament filter, and its application in water treatment. Typically, the slot width per suction bar is less than or equal to 8 mm, depending on the filter type, the application of the filament filtration, and the properties of the filament (design of the filament fiber layer and filament fiber support structure).A Ts of less than or equal to 8 and a slot width of less than or equal to 8 mm, for example, enable a reduction in backwash water volume of at least 20% and an increase in the solids content of the backwash water of at least 20% compared to conventional fiber filters, while maintaining or improving the regenerability of the fiber material or fiber layer and achieving equivalent or better filtration performance with regard to effluent quality. This advantage applies both with new fiber material (t=0) and after a certain operating period, for example, one week, six months, or one year. Furthermore, the edge in the suction slot that contacts the fiber layer can be rounded, sharp-edged, or a combination of both. The suction bar with the slot width is formed by differently shaped suction lips.The suction slot is in direct contact with the polar fiber layer or polar material of the polar material filter.

[0037] A further embodiment of the invention consists in the area of ​​the flow-relevant pores being between 0.3 mm 2 and 6 mm 2 preferably between 0.4 mm 2 and 4 mm 2 , preferably between 0.6 mm 2 and 3 mm 2 , preferably between 0.8 mm 2 and 2.5 mm 2 , particularly preferably between 1 mm 2 and 2 mm 2 lies.

[0038] Flow-relevant pores include, for example, openings in the polar material support structure with a length > 600 pm and a width > 600 pm, abbreviated > 600 pm x 600 pm, in particular > 700 x 700 pm, preferably > 800 x 800 pm, further preferably > 900 x 900 pm, further preferably > 1000 x 1000 pm, further preferably > 1100 x 1100 pm, further preferably > 1200 x 1200 pm, further preferably > 1300 x 1300 pm, further preferably > 1400 x 1400 pm, further preferably > 1500 x 1500 pm, further preferably > 1600 x 1600 pm, further preferably > 1700 x 1700 pm, further preferably > 1800 x 1800 pm, further preferably > 1900 x 1900 pm, more preferably > 2000 x 2000 pm, more preferably > 2100 x 2100 pm, more preferably > 2200 x 2200 pm, particularly preferably > 2300 x 2300 pm; very preferably > 2400 x 2400 pm, and most preferably > 2500 x 2500 pm. The area of ​​the flow-relevant pores is, for example, > 0.36 mm². 2 preferably > 0.49 mm 2 , preferably > 0.64 mm 2, further preferred > 0.81 mm 2 , preferably > 1.00 mm 2 , preferably > 1.21 mm 2 , further preferred > 1.44 mm 2 , further preferred > 1.69 mm 2 , further preferred > 1.96 mm 2 , preferably > 2.25 mm 2 , further preferred > 2.56 mm 2 , further preferred > 2.89 mm 2 , further preferred > 3.61 mm 2 , preferably > 4 mm 2 , further preferred > 4.41 mm 2 , further preferred > 4.84 mm 2 , especially preferred > 5.29 mm 2 ; especially preferred > 5.76 mm 2 , and most preferably > 6.25 mm 2 In particular, the flow-relevant pores do not necessarily have to be rectangular, depending on the type of polar material carrier structure.

[0039] Depending on the polar material carrier structure, flow-relevant and / or non-flow-relevant pores can be, for example, circular, rhomboid, trapezoidal, star-shaped, or a mixture thereof. A further embodiment of the invention consists in the fluid velocity in the suction slot being between 10 and 200 cm / s, preferably between 15 and 100 cm / s, and particularly preferably between 20 and 80 cm / s.

[0040] The fluid velocity in the suction slot (vs) can be determined experimentally by measuring the flow rate in the backwash line downstream of the suction slot and the area of ​​the suction slot. This involves evaluating a series of individual measurements. During backwashing, the filament layer is fluidized by the filtrate drawn from the filter interior by the filter cleaning pump, thus reversing the flow direction. Filter cleaning, or backwashing, is performed by a suction lip with a defined suction slot area.

[0041] A further embodiment of the invention consists in the fluid velocity in the flow-relevant pores (VP) being between 0.5 and 25 m / s, preferably between 0.8 and 15 m / s, particularly preferably between 1 and 12 m / s.

[0042] The fluid velocity in the flow-relevant pores (VP) can be determined experimentally by measuring the flow rate in the rinsing water line downstream of the suction slot and the area of ​​the suction slot, as well as by imaging to determine the area and number of flow-relevant pores. This involves evaluating a series of individual measurements or images. Any leakage water, such as that flowing horizontally from the pile fiber layer, is disregarded.

[0043] A further embodiment of the invention consists in the ratio of the fluid velocity in the suction slot (vs) and the fluid velocity in the flow-relevant pores (VP) being between 0.05 and 0.5, preferably between 0.1 and 0.4, more preferably between 0.12 and 0.35 and particularly preferably between 0.15 and 0.3.

[0044] It is advantageous that the fluidization of the pole fibers or the pole fiber layer is between 5 and 100%, preferably between 20 and 95%, and particularly preferably between 40 and 90%.

[0045] Fluidization is measured using high-resolution optical imaging in the slot of the suction bar during filter cleaning. The measurement is taken at time t=0. The fluidization of the pole fibers or the pole fiber layer serves as an indicator of the release or removal of adhering and / or embedded organic and / or inorganic substances from the pole fiber layer or the pole fibers. 100% fluidization corresponds to the maximum erection of the pole fibers or the pole fiber layer during filter cleaning, while 0% fluidization represents the opposite. Depending on the specific application, operation, and technical specifications of the pole filter, a fluidization level of 5% to 100% is required to ensure the long-term operation of the pole filter.

[0046] A further embodiment of the invention consists in the rotational speed of the polarizing filter at the extraction device or of the extraction device along the polarizing filter being between 1 and 1000 mm / s, preferably between 10 and 500 mm / s, particularly preferably between 25 and 400 mm / s.

[0047] The polarizing filter is used in a water treatment plant. The polarizing filter is mounted, for example, on a disc (disc filter) consisting of individual segments, a drum (drum filter / pressure drum filter), a plate (plate filter), or a grid support with a diamond-shaped cross-section (diamond filter).

[0048] A further embodiment of the invention consists in the filter speed of the polar material filtration being between 0 and 60 m / h, preferably between 0.5 and 40 m / h, particularly preferably between 1 and 20 m / h.

[0049] A further embodiment of the invention consists in the slot length of the extraction slot being between 0.05 and 5 m, preferably between 0.1 and 3 m, particularly preferably between 0.15 and 2 m.

[0050] It is advantageous if the pile fibers are standard, micro or ultra fibers.

[0051] In particular, the use of the polarizing filter for water treatment and / or wastewater treatment is part of the invention.

[0052] The invention will now be explained in more detail using exemplary embodiments. These show

[0053] Fig. 1 Cross-sections of a suction bar with the inventive pole material,

[0054] Fig. 2 Diagrams illustrating the mean fluid velocity in the suction slot vs as a function of the fluidization (a), the mean fluid velocity in the flow-relevant pores of the polar material carrier structure in the slot area of ​​the suction bar VP (b), and the vacuum in the suction slot (c) for different values ​​of the ratio of slot area per suction bar As and the area of ​​the flow-relevant pores of the polar material carrier structure in the slot area per suction bar, Ap

[0055] Fig. 3 shows a top view of a pole material according to the invention,

[0056] Fig. 4 Top views of various pole materials according to the invention,

[0057] Fig. 5 Top views of various polar material support structures of polar materials according to the invention,

[0058] Fig. 6 Cross-sections through the inventive pole material,

[0059] Fig. 7 shows a top view of a polar material according to the invention in the polar material filter in the slotted surface of a suction bar.

[0060] Fig. 1 shows an exemplary cross-sectional view of suction bars with the relevant slot width 7 for calculating the slot area per suction bar As. Figures (a), (b), (c), (d), (e), (f) and (g) show suction bars 8 with differently shaped suction lips. The suction slot 2 is in direct contact with the pile fiber layer or pile material of the pile filter 1.

[0061] Fig. 2 shows the mean fluid velocity in the suction slot vs as a function of the fluidization (a), the mean fluid velocity in the flow-relevant pores of the polar material carrier structure in the slot area of ​​the suction bar VP (b), and the vacuum in the suction bar (c) for different values ​​of the ratio of slot area per suction bar As and the area of ​​the flow-relevant pores of the polar material carrier structure in the slot area per suction bar Ap. The experimental setup for determining the fluidization and vacuum as a function of the fluid velocity in the suction slot (vs) and fluid velocity in the flow-relevant pores (VP) is as follows. The polar material filtration is a drum filter version with a polar material filter area of ​​0.5 m². 2 The filtration of the pollen was carried out at different filter speeds of 0-30 m / h and 0-30 m / h respectively. 3 / m 2The filter operates with a flow rate of [flow rate] per hour per filter area using biologically treated wastewater. Polar fiber filtration is an outside-in filtration process in which the water flows through the polar fiber filter and the solids are retained as they pass through the polar fiber layer. During the cleaning process (inside-out cleaning), the solids on and from the polar fiber layer are removed without interrupting the actual filtration process. During backwashing, the polar fiber layer is fluidized by the filtrate drawn from the filter interior by the filter cleaning pump, thus reversing the flow direction. Filter cleaning, or backwashing, is performed by a suction lip with a defined suction slot area. The filter drum moves along the suction lip at a defined speed (between 1 and 500 mm / s). After backwashing, the fibers align themselves according to the direction of rotation.Filter cleaning is triggered at a specific water level in the filter tank or after a defined time between backwash cycles. Settled sludge in the filter tank is also periodically removed by a settling sludge pump. Inlet and backwash water are measured with flow meters. The water level in the filter tank and riser chamber is continuously monitored with level sensors. Additionally, the negative pressure of the filter cleaning pump is monitored with a pressure sensor in the suction bar chamber. Fluidization is measured using high-resolution optical imaging in the slot of the suction bar during filter cleaning. The fluidization of the pile fibers or the pile fiber layer serves as an indicator of the release or removal of adhering and / or embedded organic and / or inorganic substances from the pile fiber layer or the pile fibers. 100% fluidization corresponds to the maximum erection of the pile fibers.The fluidization of the polarizing fiber layer during filter cleaning is reduced, while 0% fluidization represents the opposite. Depending on the specific application, operation, and technical specifications of the polarizing filter, a fluidization level of 5% to 100% is required to ensure the long-term operation of the polarizing filter. The fluidization level is determined by capturing a sequence of individual images. This sequence of images is then analyzed using image analysis techniques.

[0062] Fig. 3 showed an exemplary representation of a pile material 1 with a pile support structure 3 with pile nubs, flow-relevant pores 5, and non-flow-relevant pores 6, using a woven fabric as an example. The flow-relevant pores 5 are not closed by the pile fibers. For example, the pile fibers are not guided through the flow-relevant pores 5. Flow-relevant pores 5 are defined as the openings in the pile support structure 3 that remain permeable to the fluid even in the event of incipient fouling and / or scaling. Flow-relevant pores 5 include, for example, openings with a length > 600 pm and a width > 600 pm, abbreviated > 600 pm x 600 pm, preferably > 800 x 800 pm, and particularly preferably > 900 x 900 pm. Especially preferred are dimensions > 1000 x 1000 pm, and most preferred are dimensions > 1200 x 1200 pm and / or with an area > 0.36 mm². 2 preferably > 0.64 mm 2 , especially preferably > 0.81 mm 2; especially preferred > 1.0 mm 2 , and most preferably > 1.44 mm 2 .

[0063] Figure 4 shows an exemplary representation of a pile fabric with a distribution of the pile nubs, using the fabric in the pile carrier structure 3 as an example, as a regular checkerboard pattern (a) and a line pattern (b). In the checkerboard pattern, flow-relevant pores 5 and pile nubs 10 alternate both in the horizontal row (right to left) and in the vertical column (top to bottom). In the line pattern, vertical columns (top to bottom) with flow-relevant pores 5 alternate with columns containing pile nubs 10. The non-flow-relevant pores (6) are not shown.

[0064] Figure 5 shows an exemplary representation of the pile support structure 3 implemented as a woven fabric (a), knitted fabric (b), and nonwoven fabric (c). The pile support structure 3 can, for example, be implemented as a woven fabric, knitted fabric, or nonwoven fabric. A woven fabric is a textile fabric consisting of at least two yarn systems (warp or weft) that intersect at an angle of exactly or approximately 90° when viewed from the fabric surface. A knitted fabric is a textile fabric consisting of yarn systems produced by loop formation on a knitting machine. A knitted fabric is a fabric produced by knitting. While in knitting the entire row of stitches is created at once, in knitting the stitches are formed sequentially.

[0065] Figure 6 shows an exemplary representation of the pole nubs as W-nubs (a), V-nubs (b), and the filter-active pole fiber layer in the effective filter state with correspondingly flat-lying pole fibers 4 (c), as well as the representation of the flow direction after fluidization 9 of the suction bar. Figure 7 shows a pole filter 1 with flow-relevant pores 5 and non-flow-relevant pores 6 in the slot area per suction bar 7. List of reference symbols

[0066] 1 Polarizing filter

[0067] 2 extraction slots

[0068] 3 Polar material carrier structure

[0069] 4 pile fibers

[0070] 5 flow-relevant pores

[0071] 6 non-flow-relevant pores

[0072] 7 slot areas per suction bar

[0073] 8 suction bars

[0074] 9 Stroke direction after fluidization 10 Pollen bumps

Claims

REQUIREMENTS 1. Water treatment plant for filtration of filaments with at least one suction slot (2) for backwashing and a filament filter (1) with filament fibers (4) attached to a filament support structure (3), characterized in that the filament support structure (3) has open, flow-relevant pores (5), wherein the ratio of slot area per suction bar (7) and the area of ​​the flow-relevant pores (5) of the filament support structure (3) in the slot area per suction bar (7) is between 1.1 and 9.5, preferably between 1.25 and 9, more preferably between 1.5 and 8.5, more preferably between 2 and 8, more preferably between 2.25 and 7.5 and particularly preferably between 2.5 and 7.

2. Polarizing filter according to claim 1, characterized in that the slot width of the suction slot (2) is between 0.1 mm and 8 mm, preferably between 0.25 mm and 7 mm, more preferably between 0.5 mm and 6.5 mm, more preferably between 0.75 mm and 6 mm and particularly preferably between 1 mm and 5.5 mm.

3. Polarizing filter according to one of claims 1 or 2, characterized in that the area of ​​the flow-relevant pores is between 0.3 mm 2 and 6 mm 2 preferably between 0.4 mm 2 and 4 mm 2 , preferably between 0.6 mm 2 and 3 mm 2 , preferably between 0.8 mm 2 and 2.5 mm 2 , particularly preferably between 1 mm 2 and 2 mm 2 lies.

4. Polarizing filter (1 ) according to one of the preceding claims, characterized in that the fluid velocity in the suction slot (2) is between 10 and 200 cm / s, preferably between 15 and 100 cm / s, particularly preferably between 20 and 80 cm / s.

5. Polarizing filter (1) according to one of the preceding claims, characterized in that the fluid velocity in the flow-relevant areas pores (5) between 0.5 and 25 m / s, preferably between 0.8 and 15 m / s, particularly preferably between 1 and 12 m / s.

6. Polarizing filter (1 ) according to one of the preceding claims, characterized in that the ratio of the fluid velocity in the suction slot (vs) and the fluid velocity in the flow-relevant pores (vp) is between 0.05 and 0.5, preferably between 0.1 and 0.4, more preferably between 0.12 and 0.35 and particularly preferably between 0.15 and 0.

3.

7. Polar material filter (1 ) according to one of the preceding claims, characterized in that the fluidization of the polar fibers (4) or the polar fiber layer is between 5 and 100%, preferably between 20 and 95%, particularly preferably between 40 and 90%.

8. Polarizing filter (1 ) according to one of the preceding claims, characterized in that the rotational speed of the polarizing filter at the extraction device or of the extraction device along the polarizing filter is between 1 and 1000 mm / s, preferably between 10 and 500 mm / s, particularly preferably between 25 and 400 mm / s.

9. Polar material filter (1 ) according to one of the preceding claims, characterized in that the filter velocity of the polar material filtration is between 0 and 60 m / h, preferably between 0.5 and 40 m / h, particularly preferably between 1 and 20 m / h.

10. Polarizing filter (1 ) according to one of the preceding claims, characterized in that the slot length of the suction slot (2) is between 0.05 and 5 m, preferably between 0.1 and 3 m, particularly preferably between 0.15 and 2 m.

11. Polarizing filter (1 ) according to one of the preceding claims, characterized in that the polarizing fibers (4) are standard, micro or ultrafibers.

12. Use of a polarizing filter (1) according to any of the preceding claims for water treatment and / or wastewater treatment.

Images