Poling material for filtration

Abstract

The present invention relates to a pole material for pole material filtration with pole fibers attached to a support structure, wherein the pole fibers form a pole fiber layer above the support structure.Within the scope of the invention, it is proposed that the ratio of the average height of the pile fiber layer in the filter-active state and the average pile fiber height in the non-filter-active state is greater than 0.55, that in the case of a standard fiber the ratio of the average height of the pile fiber layer in the filter-active state and the average pile fiber height in the non-filter-active state is greater than 0.6, wherein in the case of a microfiber the ratio of the average height of the pile fiber layer in the filter-active state and the average pile fiber height in the non-filter-active state is greater than 0.55, and wherein in the case of an ultrafiber the ratio of the average height of the pile fiber layer in the filter-active state and the average pile fiber height in the non-filter-active state is greater than 0.4.

Description

The present invention relates to a pole material for pole material filtration with pole fibers attached to a support structure, wherein the pole fibers form a pole fiber layer above the support structure. Polar materials for polar material filtration are known. German patent DE 196 24 483 A1 relates to a filter cloth for liquid filtration, designed as a long-pile pile fabric. The pile fibers of the pile fabric lie on the upstream side and fold over against the support fabric during filtration, forming a depth filter. During backwashing, the pile fibers are straightened by the backwash flow, releasing dirt particles. Backwashing is carried out by means of a suction bar moving across the front of the cloth, which simultaneously acts mechanically on the pile fibers to facilitate a sudden straightening of the pile fibers during backwashing and their subsequent flattening afterward. Certain terms are explained in more detail below in the context of the present invention. A fiber is a small textile component. It is a linear, basic structure made of a material. Fibers have an external shape (longitudinal shape: smooth, plain, or crimped; cross-sectional shape: round, angular, etc.) and are solid or hollow. They can be continuous (filament) or of limited length (staple fiber). A composite fiber is a fiber made from a combination of different materials to achieve specific properties such as strength, lightness, or other desired characteristics. This type of fiber consists of at least two different types of fibers or materials, which are processed together in a spliced ​​fiber (composite) or separately. A nonwoven fabric is a structure made of fibers of limited length, continuous fibers or cut yarns that are brought together and bonded to form a fiber layer. A knitted fabric is a textile fabric made from thread 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 one after the other. A thread is a collective term for linear textile structures. At least two yarns are joined together by twisting (twisting). A yarn is a linear textile structure made up of several fibers. A wrapping yarn is a yarn that is created by wrapping or sheathing a core yarn with an additional fiber material. A filament is a fiber with a practically unlimited length (at least 1,000 mm). Filaments are also referred to as continuous fibers. A monofilament is a single filament. Ultra-fine monofilaments are filaments with an equivalent diameter of less than 0.03 mm (30 µm). A multifilament is a bundle of monofilaments. A staple fiber is a fiber with a limited length (less than 1,000 mm). A distinction is made between long staple fibers (< 600 mm), medium staple fibers (< 60 mm), and short staple fibers (< 40 mm). A ply is the number of simple yarns and / or pre-twists contained in plied yarns or threads. A woven fabric is a textile surface structure made up of at least two thread systems (warp or weft) that intersect in a pattern at an angle of exactly or approximately 90° when viewed from the surface of the woven fabric. A pile fabric is a multidimensional structure consisting of a fluidizable, filter-active fiber layer (pile fiber layer) and a backing fabric or support structure. Within the scope of the present invention, a pile fabric can also be designed wholly or partially as a loop fabric, i.e., comprising uncut loops. A backing fabric or support structure is a textile surface with large, flow-relevant, non-filter-active pores that serves as a support for the pile fiber layer. Pile nubs are attached to this support. Flow-relevant pores are defined as the openings in the support structure that remain permeable to the fluid even in the event of scaling or fouling. Scaling refers to the deposition of minerals, such as calcium carbonate, on the surfaces of the pile filter. Scaling can lead to blockages and increased pressure drop, which can impair the effectiveness of the entire water or wastewater treatment system. Fouling refers to the accumulation of unwanted substances, such as organic materials, sludge, microorganisms, and other particles, on the surface and within the pores of pile filters.Flow-relevant pores include, for example, openings with a length ≥ 100 µm and a width ≥ 100 µm, abbreviated as ≥ 100 µm × 100 µm, in particular ≥ 200 × 200 µm, preferably ≥ 400 × 400 µm, particularly preferably ≥ 800 × 800 µm; very preferably ≥ 1,000 × 1,000 µm, and most preferably ≥ 1,200 × 1,200 µm. A pile fiber layer is a layer consisting of numerous individual fibers. These individual fibers (the poles) are bundled into nubs (pile nubs) and connected to the support structure. 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. The pole material can be defined, among other things, by the height of the erect pole fibers, the diameter of the individual filaments, the specific surface area of ​​the pole fibers, the basis weight of the pole material fabric, and the size of the flow-relevant pores of the support structure. A defined pore size for the deposition of particles / solids for pole materials or the pole fiber layer does not exist. 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 filter medium). In addition to the sieving effect, true filtration effects occur along the depth of the pile fiber layer. Pile filtration represents an important subfield of cloth filtration and is used particularly for water and wastewater treatment. Three-dimensional filter media, known as piles, are used in pile filtration.The filter 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). In conventional filtration materials, the pile fibers lie almost flat against the support structure when in the active filter state. The pile fibers are oriented perpendicular to the filtration direction. A disadvantage of this is that the pile material must be stood upright for effective backwashing to clean the spaces between the pile fibers. Sludge thickening is a process in wastewater and sludge treatment in which the water content of sludge is reduced to decrease its volume. Sludge thickening refers to the physical separation of water and solids in the sludge with the aim of increasing the solids content (dry matter content) to typically 1-10%. The invention is based on the objective of providing an improved slurry material for filtration and / or sludge thickening. The problem is solved for a pile fiber material for pile filtration with pile fibers attached to a support structure, wherein the pile fibers form a pile fiber layer above the support structure, by ensuring that, for a standard fiber, the ratio of the average height of the pile fiber layer in the filter-active state and the average pile fiber height in the non-filter-active state is greater than 0.6, for a microfiber, the ratio of the average height of the pile fiber layer in the filter-active state and the average pile fiber height in the non-filter-active state is greater than 0.55, and for an ultrafiber, the ratio of the average height of the pile fiber layer in the filter-active state and the average pile fiber height in the non-filter-active state is greater than 0.4. The ratio of the average height of the polar fiber layer in the filter-active state (dfilteractive) to the polar fiber height in the non-filter-active state (HF) corresponds to the degree of compression. The average height of the pile fiber layer and the average pile fiber height can be calculated by taking the arithmetic mean of the respective length measurements. These length measurements can be taken at, for example, 5 different locations. A measurement to determine the ratio of the average height of the pile fiber layer in the filter-active state to the average pile fiber height in the non-filter-active state can be performed as follows. To determine the average height of the pile fiber layer and the average pile fiber height, a strip of pile fabric (for example, approximately 4.0 cm × 8.0 cm) is cut and fixed vertically, for example, with clamps. The pile fabric strip should be prepared so that the direction of the pile fiber layer is longitudinal. First, the strip is placed under a microscope so that the support structure is not visible. A microscopic image is taken, and the average pile fiber height in the dry state is measured. The average pile fiber height depends not only on the length of the pile fibers used but also on the way in which the pile fibers are embedded in the support structure.The pile fiber height can, for example, be half the pile fiber length reduced by the length of the integration into the support structure. To measure the average height of the pile fiber layer in the wet, filter-active state, the strip is immersed in tap water for approximately 60 seconds, patted twice under pressure in the direction of the pile, and then weighted down with a weight of approximately 500 g (which extends about 25% beyond the surface area of ​​the pile strip) for approximately 60 seconds. After this treatment, the strip is fixed again, and a microscopic image is taken. The average height of the pile fiber layer in the filter-active state is then measured. To increase accuracy, at least five measurements must be taken with five different pile strips of the same material, and the values ​​then averaged. The height of the pile fiber layer in the wet state corresponds approximately to the height of the pile fiber layer in the filter-active state. In known polarizing materials, the polar fibers lie almost flat against the support structure in the filter-active state, with the polar fibers oriented orthogonally to the filtration direction. The polarizing material according to the invention, however, provides for the polar fibers to be arranged ideally almost parallel to the filtration direction in the filter-active state. This orientation is intended exclusively during filtration, not during backwashing or filter cleaning. The adapted orientation of the polar fibers enables more efficient cleaning. The polar material according to the invention has the property that the polar fibers no longer lie (completely) flat against the support structure, with the polar fibers being arranged almost parallel to the filtration direction in the filter-active state. The pile height of known pile materials used in water treatment is approximately 12 to 16 mm. The shorter the pile height, the higher the likelihood of the pile layer being ribbed. Depending on the orientation of the ribs—a kind of profiling of the pile material independent of the cleaning device—a targeted surface cleaning or surface water flow, originating not primarily from the reverse side of the pile material, can be achieved. Targeted structuring of the pile layer before or after cleaning is also conceivable. For example, the surface area of ​​the pile layer can be increased by grooving. Similarly, the pile fibers of the pile layer can be parallelized, for example, by using a brush. A compression level of 1 indicates that the pile fibers are almost parallel to the filtration direction in the filter-active state, while a compression level of 0 indicates that they are almost perpendicular to the filtration direction. During filter cleaning of the improved pile material, the pile fiber layer is compressed by the flow-induced negative pressure. This causes the fibers to move against each other, creating internal friction within the pile fiber layer, which leads to more efficient cleaning. The greater the compression of the pile fiber layer, the lower the (air) permeability of the pile material. The degree of compression, in combination with the equivalent fiber diameter or fiber fineness / thickness (dtex) and the pile fiber density, is a measure of the pore channels in the pile fiber layer. Current pile filters can be classified into three categories based on their fiber diameter: standard, micro, and ultrafibers. Today, standard fibers with an equivalent fiber diameter ≥ 10 µm, microfibers with an equivalent fiber diameter ≥ 5 µm - < 10 µm, and ultrafibers with an equivalent fiber diameter < 5 µm are the most common pile filters used in water treatment for municipal and industrial applications. Conventional piles have a dfilteractive / HF value of up to 0.55. The following degrees of compression, grouped by equivalent fiber diameter, are known. - Standard fiber ≥ 10 µm: Compression ratio ~ 0.4 - 0.55 - Microfiber ≥ 5 - < 10 µm: Compression ratio ~ 0.39 - 0.49 - Ultrafiber < 5 µm: Compression ratio ~ 0.27 The inventive pile fabric with standard fiber has a dfilteractive / HF ratio ≥ 0.60. The dfilteractive / HF ratio is, for example, ≥ 0.60, preferably ≥ 0.625, more preferably ≥ 0.65, more preferably ≥ 0.70, more preferably ≥ 0.725, more preferably ≥ 0.75, more preferably ≥ 0.775, more preferably ≥ 0.80, more preferably ≥ 0.825, more preferably ≥ 0.85, more preferably ≥ 0.875, more preferably ≥ 0.90, more preferably ≥ 0.925, particularly preferably ≥ 0.95; most preferably ≥ 0.975, and most preferably 1.0. The microfiber-based pile fabric according to the invention has a dfilteractive / HF ratio ≥ 0.55. The dfilteractive / HF ratio is, for example, ≥ 0.55, preferably ≥ 0.60, more preferably ≥ 0.65, more preferably ≥ 0.70, more preferably ≥ 0.725, more preferably ≥ 0.75, more preferably ≥ 0.775, more preferably ≥ 0.80, more preferably ≥ 0.825, more preferably ≥ 0.85, more preferably ≥ 0.875, more preferably ≥ 0.90, more preferably ≥ 0.925, particularly preferably ≥ 0.95; most preferably ≥ 0.975, and most preferably 1.0. The inventive polar fabric with ultrafiber has a ratio dfilteractive / HF≥ 0.40. The ratio dfilteractive / HFist, for example, ≥ 0.40, preferably ≥ 0.425, further preferably ≥ 0.45, further preferably ≥ 0.50, further preferably ≥ 0.55, further preferably ≥ 0.60, further preferably ≥ 0.65, further preferably ≥ 0.65, further preferably ≥ 0.70, further preferably ≥ 0.725, further preferably ≥ 0.75, further preferably ≥ 0.775, further preferably ≥ 0.80, further preferably ≥ 0.825, further preferably ≥ 0.85, further preferably ≥ 0.875, further preferably ≥ 0.90, further preferably ≥ 0.925, particularly preferably ≥ 0.95; Most preferred ≥ 0.975, and most preferred 1.0. The degree of compression can be influenced, among other things, by using textured and thus voluminous filaments / fibers in the pile fiber layer and / or by increasing the pile fiber density of the filaments / fibers in the pile fiber layer. The pile fiber density of the filaments / fibers in the pile fiber layer can be achieved by a different distribution or increase in the number of filaments / fibers and / or by using more filaments / fibers in the pile fiber layer. The pile material according to the invention can be compacted within the pile fiber layer to such an extent that complete flattening in the filter-active state is prevented. The finer the pile fibers, i.e., the smaller the fiber thickness / fineness (dtex) or the equivalent fiber diameter, the more compact the pile fiber layer must be. Therefore, the pile material according to the invention is particularly relevant for smaller equivalent fiber / filament cross-sections or fineness (dtex).As the fiber thickness of known pole materials decreases, the fluidizability decreases, which makes the removal of adhering solids or similar substances significantly more difficult. The degree of compression decreases over time if no active countermeasure is taken, for example, through special filter cleaning. This depends on the material properties, the application, and the medium. Advantageously, the relevance of the cleaning direction is significantly reduced with the inventive pole material, since the cleaning process primarily occurs via mechanical compression and no longer exclusively via fluidization. The inventive pole material ensures increased cleaning efficiency while simultaneously offering greater operational flexibility. Particularly in rotating filter systems such as disc or drum filters, the direction of rotation, and thus the cleaning direction, can be varied, contrary to previous design principles, without causing significant or the same impairments to the separation efficiency as with known pole materials. The inventive pile material offers, among other things, the following advantages: - More accessible pore channels within the pile fiber layer, resulting in a higher solids holding capacity. This is also evident from the increased porosity. The solids / particles can thus penetrate deeper into the pile fiber layer before a filter cake forms on it. - The same basis weight of the pile fiber layer (without a support structure) with an adapted pile fiber height leads to improved filter performance. - A better point of attack for erecting the pile fibers (fluidization) during filter cleaning. - Despite a shorter pile fiber height, profiling of the pile fiber layer can be achieved in the wet state. The denser the pile fiber layer, the better it can be deformed and adapted to the filter suction.- Depending on the orientation / inclination of the pile fibers in the pile fiber layer during the filter's active state, the pile fiber layer / pile material can be tailored to the fluid matrix. - Lower fabric resistance (cm / m / h or mbar / m / h) and higher recovery, i.e., better restoration of the pile material's performance after filter cleaning. - Lower vacuum required during pile material cleaning due to increased porosity. A further embodiment of the invention consists in the fact that the polyester material has an air permeability of 10 to 5,000 l / m2 / s, preferably of 50 to 4,000 l / m2 / s, particularly preferably of 100 to 2,000 l / m2 / s and most preferably of 150 to 1,500 l / m2 / s. Among the three pile categories, standard fiber piles exhibit the highest air permeability. Microfiber piles are characterized by a lower air permeability in comparison. Ultrafiber piles exhibit the lowest air permeability within these groups. The air permeability (determined according to DIN EN ISO 9237) depends on the equivalent fiber diameter. Previous microfiber pole fabrics, for example, exhibited an air permeability of 724 ± 172 l / m² / s (n = 5) at a compression ratio of 0.49 in the filter-active state. With the microfiber pole fabric according to the invention, the air permeability at a compression ratio of 0.86 in the filter-active state is, for example, 353 ± 41 l / m² / s (n = 5). Previous ultrafiber pole fabrics, for example, exhibited an air permeability of 415 ± 45 l / m² / s (n = 5) at a compression ratio of 0.27 in the filter-active state. With the ultrafiber pole fabric according to the invention, the air permeability at a compression ratio of 0.84 in the filter-active state is, for example, 304 ± 23 l / m² / s (n = 5). A further embodiment of the invention consists in the fact that the pile fiber layer has a basis weight between 100 and 10,000 g / m2, preferably between 200 and 5,000 g / m2, particularly preferably between 250 and 1,500 g / m2. The basis weight of the entire pile material is, for example, between 200 and 15,000 g / m2, preferably between 300 and 6,000 g / m2, particularly preferably between 400 and 1,800 g / m2. The following pole fiber densities are known, grouped by equivalent fiber diameter. - Standard fiber ≥ 10 µm: Polar fiber density ~ 40 - 57 g / m² / mm² - Microfiber ≥ 5 - < 10 µm: Pile fiber density ~ 37 - 44 g / m² / mm² - Ultrafiber < 5 µm: Polar fiber density ~ 31 g / m² / mm The pile material according to the invention with standard fiber has a pile fiber density ≥ 60 g / m2 / mm. The pile fiber density is, for example, ≥ 60 g / m² / mm, preferably ≥ 65 g / m² / mm, further preferably ≥ 70 g / m² / mm, further preferably ≥ 75 g / m² / mm, further preferably ≥ 80 g / m² / mm, further preferably ≥ 85 g / m² / mm, further preferably ≥ 90 g / m² / mm, further preferably ≥ 95 g / m² / mm, further preferably ≥ 100 g / m² / mm, further preferably ≥ 110 g / m² / mm, further preferably ≥ 120 g / m² / mm, further preferably ≥ 130 g / m² / mm, further preferably ≥ 140 g / m² / mm, particularly preferably ≥ 150 g / m² / mm; most preferred ≥ 175 g / m2 / mm, and most preferred ≥ 200 g / m2 / mm. The inventive pile fabric with microfiber has a pile fiber density ≥ 50 g / m2 / mm. The pile fiber density is, for example, ≥ 50 g / m² / mm, preferably ≥ 55 g / m² / mm, further preferably ≥ 60 g / m² / mm, further preferably ≥ 70 g / m² / mm, further preferably ≥ 75 g / m² / mm, further preferably ≥ 80 g / m² / mm, further preferably ≥ 85 g / m² / mm, further preferably ≥ 90 g / m² / mm, further preferably ≥ 95 g / m² / mm, further preferably ≥ 100 g / m² / mm, further preferably ≥ 110 g / m² / mm, further preferably ≥ 120 g / m² / mm, further preferably ≥ 130 g / m² / mm, further preferably ≥ 140 g / m² / mm, particularly preferably ≥ 150 g / m² / mm. g / m2 / mm; most preferably ≥ 175 g / m2 / mm, and most preferably ≥ 200 g / m2 / mm. The inventive pile material with ultrafiber has a pile fiber density ≥ 40 g / m2 / mm. The pile fiber density is, for example, ≥ 40 g / m² / mm, preferably ≥ 45 g / m² / mm, further preferably ≥ 50 g / m² / mm, further preferably ≥ 55 g / m² / mm, further preferably ≥ 60 g / m² / mm, further preferably ≥ 65 g / m² / mm, further preferably ≥ 70 g / m² / mm, further preferably ≥ 75 g / m² / mm, further preferably ≥ 80 g / m² / mm, further preferably ≥ 85 g / m² / mm, further preferably ≥ 90 g / m² / mm, further preferably ≥ 95 g / m² / mm, further preferably ≥ 100 g / m² / mm, further preferably ≥ 110 g / m² / mm, further preferably ≥ 120 g / m² / mm. further preferably ≥ 130 g / m2 / mm, further preferably ≥ 140 g / m2 / mm, particularly preferably ≥ 150 g / m2 / mm; very preferably ≥ 175 g / m2 / mm, and most preferably ≥ 200 g / m2 / mm. The pile fiber density in the pile fiber layer can also be represented by the ratio of the areal weight of the pile fiber layer (without support structure; mPole fiber layer) and the erected pile fiber height in the non-filter-active state (Note: pile fiber height and nub length are directly proportional) (HF): The areal weight of the pile fiber layer (without support structure; mPole fiber layer) is approximately calculated from the total areal weight of the pile material minus the areal weight of the support structure. One embodiment of the invention consists in the fact that the degree of inclination of the pole fiber layer lies between 30° and 90°. The inclination of the polar fiber layer in the filter-active state describes the angle at which the polar fibers protrude relative to the filtration direction / flow direction and the support structure. The starting point for determining the inclination is the integration of the polar fiber into the support structure. • 0°: Polar fiber layer is perpendicular to the filtration direction and parallel to the support structure. • 90°: Polar fiber layer is parallel to the filtration direction and perpendicular to the support structure. • Intermediate values: The polar fiber layer is arranged at an angle to the flow direction. The angle of inclination is determined by the line connecting the point where the polar fiber is embedded in the support structure and its endpoint at the transition surface to the polar fiber layer of the filter medium. In the prior art, standard, micro, and ultrafibers typically exhibit an angle of inclination of approximately 5 to 15 degrees in the filter-active state. The pole material according to the invention, on the other hand, preferably has an angle of inclination of ≥ 30 degrees, more preferably ≥ 32.5 degrees, more preferably ≥ 35 degrees, more preferably ≥ 37.5 degrees, more preferably ≥ 40 degrees, more preferably ≥ 42.5 degrees, more preferably ≥ 45 degrees, more preferably ≥ 47.5 degrees, more preferably ≥ 50 degrees, more preferably ≥ 55 degrees, more preferably ≥ 60 degrees, more preferably ≥ 65 degrees, more preferably ≥ 70 degrees, more preferably ≥ 75 degrees, particularly preferably ≥ 80 degrees; most preferably ≥ 85 degrees, and most preferably 90 degrees. The more vertically the pile fiber layer is aligned, the less influence the direction of stroke and the direction of cleaning or rotation. The degree of compression and the tilt angle can be increased by the presence of particles, solids, or by the formation of biofilm and / or scaling effects in the pile fiber layer during operation. When determining the degree of compression and the tilt angle, such influences must be excluded or minimized. A further embodiment of the invention consists in the pile fibers having a fiber thickness between 0.001 and 700 dtex, preferably between 0.005 and 500 dtex, particularly preferably between 0.01 and 435 dtex. For a polyethylene terephthalate (PET) fiber, in textile engineering polyester (PES) with a density of 1.38 g / cm3, a fiber thickness of 0.001 to 700 dtex corresponds to an equivalent diameter of 0.3 to 254 µm, a fiber thickness of 0.005 to 500 dtex to a diameter of 0.7 to 215 µm, and a fiber thickness of 0.01 to 435 dtex to a diameter of 1.0 to 200 µm. For example, a PES ultrafiber with a fiber thickness of 0.26 dtex has a diameter of 4.9 µm, a PES microfiber with a fiber thickness of 0.6 dtex has a diameter of 7.4 µm, and a PES standard fiber with a fiber thickness of 4.6 dtex has a diameter of 20.6 µm. A further embodiment of the invention consists in the support structure having open, flow-relevant pores, wherein the ratio of slot area per suction bar and the area of ​​the flow-relevant pores of the 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. Despite the high degree of compression, the improved pole material can exhibit an open structure within the support structure. This open structure is defined by the flow-relevant pores. The filter 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). During backflushing, flow-induced negative pressure forces fluid from the back of the pile material through the pile fiber layer, reversing the flow direction locally in the area of ​​the suction slot and fluidizing the pile fiber layer. This process can dislodge any solid particles trapped in the pile fiber layer from the flow channels. This can be achieved, for example, by suction using a filter cleaning pump and / or a vacuum pump in a gravity system, or by opening a valve in a pressurized system. Backflushing can be carried out using a suction bar with one or more suction slots. The polarizing filter can be described by the following formula. where τS: ratio of slot area per suction bar to the area of ​​the flow-relevant pores of the support structure within the slot area per suction bar. AS = slot area per suction bar. AP = area of ​​the flow-relevant pores of the support structure within the slot area per suction bar. ASist 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. 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%. 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. The support structure is a textile sheet with large, flow-relevant and non-filter-active pores, serving as a carrier for the filter-active pile fiber layer. Flow-relevant pores are defined as the openings in the 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. Flow-relevant pores include, for example, openings in the support structure with a length ≥ 300 µm and a width ≥ 300 µm, abbreviated as ≥ 300 µm × 300 µm, in particular ≥ 350 × 350 µm, in particular ≥ 400 × 400 µm, in particular ≥ 450 × 450 µm, in particular ≥ 500 × 500 µm, in particular ≥ 550 × 550 µm, in particular ≥ 600 × 600 µm, in particular ≥ 700 × 700 µm, preferably ≥ 800 × 800 µm, further preferably ≥ 900 × 900 µm, more preferably ≥ 1000 × 1000 µm, more preferably ≥ 1100 × 1100 µm, more preferably ≥ 1200 × 1200 µm, more preferably ≥ 1300 × 1300 µm, more preferably ≥ 1400 × 1400 µm, more preferably ≥ 1500 × 1500 µm, more preferably ≥ 1600 × 1600 µm, more preferably ≥ 1700 × 1700 µm, more preferably ≥ 1800 × 1800 µm, more preferably ≥ 1900 × 1900 µm, more preferably ≥ 2000 × 2000 µm, more preferably ≥ 2100 × 2100 µm, more preferably ≥ 2200 × 2200 µm, particularly preferably ≥ 2300 × 2300 µm; very preferably ≥ 2400 × 2400 µm, and most preferably ≥ 2500 × 2500 µm.The area of ​​the flow-relevant pores is, for example, ≥ 0.09 mm², preferably ≥ 0.1225 mm², preferably ≥ 0.16 mm², preferably ≥ 0.2025 mm², preferably ≥ 0.25 mm², preferably ≥ 0.3025 mm², preferably ≥ 0.36 mm², preferably ≥ 0.49 mm², more preferably ≥ 0.64 mm², more preferably ≥ 0.81 mm², more preferably ≥ 1.00 mm², more preferably ≥ 1.21 mm², more preferably ≥ 1.44 mm², more preferably ≥ 1.69 mm², more preferably ≥ 1.96 mm², more preferably ≥ 2.25 mm², more preferably ≥ 2.56 mm² mm², more preferably ≥ 2.89 mm², more preferably ≥ 3.61 mm², more preferably ≥ 4 mm², more preferably ≥ 4.41 mm², more preferably ≥ 4.84 mm², particularly preferably ≥ 5.29 mm²; very preferably ≥ 5.76 mm², and most preferably ≥ 6.25 mm². In particular, the flow-relevant pores do not need to be rectangular, depending on the type of support structure. 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 support structure can be determined in the slot area of ​​the suction beam. The flow-relevant pores of the support structure must meet the aforementioned requirements in the slot area. The area of ​​the flow-relevant pores of the support structure can be between 13.5% and 50%, preferably between 14% and 25%, and most preferably between 14.5% and 22% of the total area of ​​the polarizing filter. The polarizing filter and the polarizing material are described prior to use at time t = 0: Any scaling and / or fouling of the support structure is not considered in this description. Scaling and / or fouling of the 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. 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 ​​flow-relevant pores is determined in the functional state of the pile material, i.e., with the pile fibers connected to the support structure, and in the state of the pile material at time t = 0 before processing. To determine the number of flow-relevant pores, an area of ​​at least 1 cm² must be measured in at least 5 pile material samples of the same specification and an average value calculated. The number of pores is determined in the functional state of the pile filter, i.e., with the pile fibers connected to the support fabric, and in the state of the pile material at time t = 0 before processing. The number of flow-relevant pores can, for example, range from 1 to 100 1 / cm².If pole and / or back fibers or carrier fibers are located above the flow-relevant pores on the back of the support structure or if they 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. The flow-relevant pores can be arranged in a periodic pattern within the support structure, for example, as a checkerboard or line pattern. In a checkerboard pattern, flow-relevant and non-flow-relevant pores alternate in both the 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. 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 support structure has a significant influence on the pole filtration. The supporting structure can be, for example, a woven fabric, nonwoven fabric, knitted fabric or crocheted fabric. The studs can be connected to the support structure with a W-stud, a double W-stud, or a V-stud. The pile fibers in one nub and / or the pile fibers in different nubs can be different. "Different" in this context preferably means the following: • The fibers of the at least one pile nub can, for example, consist of different materials. • It is also possible that the fibers of the at least one pile nub have different equivalent diameters. • The fibers of the at least one pile nub can have different cross-sectional shapes. • The fibers of the at least one pile nub can have different textures. • Furthermore, it is also possible that the fibers of the at least one pile nub have different twists. • Finally, the fibers of the at least one pile nub can differ in their chemical and / or biodegradability. The pile fibers can include composite fibers, twisted yarns, yarns, and / or wrapping yarns. The pile fibers can be in the form of filaments or staple fibers. The larger the nub, the more stable the structure within the pile fiber layer. Simultaneously, as the size of the flow-relevant pores increases, the number of anchoring points for the pile fiber layer in the supporting structure decreases. The packing density of the pile fibers increases with each nub in the improved pile fabric. In woven fabrics, the flow-relevant pore size approximately corresponds to the dimension of the nub. It has been shown that to achieve a certain degree of compression, the larger the flow-relevant pores in the support material are, the longer the pole nub must be. Especially when the pile fabric is not flat, adapting the pile fiber layer to the curvature of the substrate can prove advantageous. This is particularly important for drum filters. Such adaptation of the pile fiber layer can be achieved, for example, by varying the pile fiber length. Exemplary embodiments of the invention are described in more detail below with reference to drawings. Figure 1 shows a cross-section of a polar material according to the invention in the non-filter-active state, Figure 2 shows a cross-section of a polar material according to the invention in the filter-active state, Figure 3 shows a cross-section of another polar material according to the invention, Figure 4 shows a cross-section of another polar material according to the invention. Figures 1, 2, 3 to 4 show the inventive pole materials 1 for pole material filtration. The pole materials 1 have a support structure 2 with pole fibers 3 attached to it. The pole fibers 3 form a pole fiber layer 4 over the support structure 2. Figure 1 shows the polar material 1 according to the invention in its non-filter-active state. In this state, the polar fibers 3 are erected and run orthogonally to the plane formed by the support structure 1. The average polar fiber height 6 in the non-filter-active state can be determined in this state. The polar fiber height in the non-filter-active state can be measured using a microscope at several positions on one or more polar materials. The measurements are then averaged over several measurements. Figure 2 shows the polar material 1 according to the invention in its filter-active state. After filter cleaning, the polar fibers 3 are aligned almost perpendicular to the filtration direction. Before and / or after filter cleaning, the polar fiber layer can be aligned or structured using structured means, for example, a comb or a brush. In this state, the average height of the polar fiber layer 5 in the filter-active state can be determined. The height of the polar fiber layer in the filter-active state can be measured with a microscope at several positions on one or more polar materials. The measurements are then averaged over several measurements. Figures 3 and 4 illustrate different methods for integrating the pile fibers 3 into the support structure 2. Figure 3 shows integration using a W-shaped stud, and Figure 4 shows integration using a V-shaped stud. When the pile fibers 3 are integrated using a V-shaped stud, the pile fiber height corresponds to approximately half the length of the integrated pile fibers. With the same length of pile fibers, the pile fiber height is lower when integrated using a W-shaped stud. The pile fiber height is reduced accordingly by the length used to integrate the pile fibers 3 into the support structure.

Claims

A pile material (1) for pile material filtration with pile fibers (3) attached to a support structure (2), wherein the pile fibers (3) form a pile fiber layer (4) above the support structure (2), characterized in that, in the case of a standard fiber, the ratio of the average height of the pile fiber layer (5) in the filter-active state and the average pile fiber height (6) in the non-filter-active state is greater than 0.6, wherein, in the case of a microfiber, the ratio of the average height of the pile fiber layer (5) in the filter-active state and the average pile fiber height (6) in the non-filter-active state is greater than 0.55, and in the case of an ultrafiber, the ratio of the average height of the pile fiber layer (5) in the filter-active state and the average pile fiber height (6) in the non-filter-active state is greater than 0.

4. The polyester material (1) according to claim 1, characterized in that the polyester material has an air permeability of 10 to 5,000 l / m2 / s, preferably of 50 to 4,000 l / m2 / s, particularly preferably of 100 to 2,000 l / m2 / s and most preferably of 150 to 1,500 l / m2 / s. Pile material (1) according to claim 1 or 2, characterized in that the pile fiber layer has a basis weight between 100 and 10,000 g / m2, preferably between 200 and 5,000 g / m2, particularly preferably between 250 and 1,500 g / m2. Pile material (1) according to one of the preceding claims, characterized in that the degree of inclination of the pile fiber layer (4) is between 30° and 90°. Pile material (1) according to one of the preceding claims, characterized in that the pile fibers (3) have a fiber thickness between 0.001 and 700 dtex, preferably between 0.005 and 500 dtex, particularly preferably between 0.01 and 435 dtex. Polstoff (1) according to one of the preceding claims, characterized in that the support structure (2) has open, flow-relevant pores, wherein the ratio of slot area per suction bar and the area of ​​the flow-relevant pores of the 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. Pile material (1) according to one of the preceding claims, characterized in that the fluidization of the pile fibers or the pile fiber layer is between 5 and 100%, preferably between 20 and 95%, particularly preferably between 40 and 90%. Pile fabric (1) according to one of the preceding claims, characterized in that the carrier structure is a woven fabric, a knitted fabric, a knitted fabric or a nonwoven fabric. Pile material (1) according to one of the preceding claims, characterized in that the pile nubs are connected to the support structure by a W-nub, a double W-nub or a V-nub. Pile material (1) according to one of the preceding claims, characterized in that the pile fibers (3) of the at least one pile nub have different cross-sectional shapes. Pile material (1) according to one of the preceding claims, characterized in that the pile fibers (3) of the at least one pile nub consist of different materials. Pile material (1) according to one of the preceding claims, characterized in that the pile fibers (3) of the at least one pile nub have different equivalent diameters. Pile material (1) according to one of the preceding claims, characterized in that the pile fibers (3) of the at least one pile nub have different textures. Pile material (1) according to one of the preceding claims, characterized in that the pile fibers (3) of the at least one pile nub have different turbulences. Pile material (1) according to one of the preceding claims, characterized in that the pile fibers (3) are in the form of staple fibers and / or yarns and / or threads.

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