Filter unit

Abstract

The invention relates to a filter unit (1) for filtering and treating a gas, such as an exhaust gas for example. The filter unit (1) has: a filter device (2) for filtering a gas, a catalyst (4) for treating the gas filtered by means of the filter device (2), an outlet (6), via which the gas treated by means of the catalyst (4) can be discharged out of the filter unit (1), and a support structure (8), on which the filter device (2) is arranged, wherein the support structure (8) delimits a chamber (81) in which the catalyst (4) is at least partly arranged. The invention additionally relates to a method for filtering and treating a gas by means of the filter unit (1) according to the invention.

Description

[0001] filter unit

[0002] The invention relates to a filter unit and a method for filtering and treating a gas such as an exhaust gas.

[0003] Processes often produce by-products that can have an undesirable impact on the environment (people, animals, plants, ecosystems, etc.). Especially in processes that involve energy conversion or manufacturing, undesirable by-products (particulate matter and / or toxic components such as NO X , SO2, HCl) are released into the environment, where they have a negative impact on the health of living beings and also on the climate.

[0004] Therefore, efforts are made to prevent the release of harmful, often toxic by-products (pollutants) into the environment during such processes. However, this is not easy, as the equipment required for the respective process often requires costly retrofitting or even new development to reduce the release of pollutants into the environment via exhaust gases. If processes are already equipped with appropriate means to reduce such release of pollutants into the environment, it may happen that the

[0005] Failure of these resources leads to costly maintenance and a complete interruption of the respective process, which can have considerable economic consequences (production downtime, interrupted energy conversion, etc.). Therefore, it is an object of the present invention to overcome the above-mentioned disadvantages, i.e., to more easily reduce the release of undesirable by-products, particularly in technical or chemical processes.

[0006] This object is achieved by the subject matter and method according to the independent claims. Advantageous further developments are the subject matter of the dependent claims.

[0007] According to a first aspect, the invention relates to a filter unit for filtering and treating a gas, such as an exhaust gas. The filter unit comprises: a filter device for filtering a gas; a catalyst for treating the gas filtered by the filter device; an outlet through which the gas treated with the catalyst can be discharged from the filter unit; and a support structure on which the filter device is arranged, wherein the support structure delimits a space in which the catalyst is at least partially arranged.

[0008] The filter unit thus provides dual purification in a single device across two stages: a first stage involves filtering the gas (i.e., the separation and retention of certain particles, such as particulate matter, which are transported via the gas), and a second stage involves treating the filtered gas with the catalyst, thus further reducing harmful (e.g., gaseous) media in the gas. This allows devices or systems, such as energy conversion plants or components (power plants, incineration plants, biogas plants, heating systems using renewable raw materials (e.g., wood pellets), natural gas plants, chimneys, etc.), to be cleaned.) or manufacturing plants (e.g. for cement production), can be easily equipped or retrofitted with the filter unit in order to achieve a significant reduction in the media released into the environment during the respective process, especially harmful ones (fine dust, toxic components such as NO. X , SO2, HCl, etc.). In particular, the two-stage cleaning of the filter unit allows a gas to be purified to such an extent that it contains virtually no particulate matter and toxic components, making it even purer than ambient air.

[0009] Furthermore, the at least partial arrangement of the catalyst in the space defined by the support structure and the arrangement of the filter device on the support structure provide a very compact filter unit. This makes it possible to easily install the filter unit at the desired location (e.g., at an exhaust outlet such as a chimney). Furthermore, thanks to its compact design, the filter unit can be used even in hard-to-reach locations, which significantly simplifies the reduction of particles (especially fine dust) and other harmful (e.g., gaseous) components in all processes.

[0010] The filter device can be arranged at least partially outside the space delimited by the support structure. This makes maintenance (replacement, cleaning, etc.) of the filter device particularly easy, since in particular access to the space delimited by the support structure is not required to maintain the filter device. The filter device can therefore also be easily provided during manufacture of the filter unit, for example by wrapping the filter device around the support structure. Preferably, the filter device is fastened to the support structure. This particularly ensures that the filter device remains in a defined position relative to the support structure under mechanical stress (for example due to flow, transport, or other influences).

[0011] The filter device can be attached to the support structure via a material bond, such as a weld (preferably a nano-weld and / or a sinter weld). This makes it particularly easy to attach the filter device to the support structure, as such attachment can be achieved, for example, via contact points between the support structure and the filter device.

[0012] In addition, this type of fastening can be easily automated, which saves time and money.

[0013] The filter device can be flat and / or have one or more layers. The filter device is thus provided in a particularly space-saving manner within the filter unit and can also be easily arranged therein. Different functions (e.g., filter stages) of the filter device can also be easily provided across the multiple layers. It is preferred if a first layer of the filter device has a higher filter fineness than a second layer of the filter device, with the first layer preferably being provided downstream of the second layer. This enables particularly good filtration by the filter device.

[0014] The filter device preferably has a cylindrical and / or tubular shape. This means that the one or more layers comprising the filter device can form a shape corresponding to a cylinder or tube (for example, by being arranged on the support structure or wrapped around the support structure).

[0015] The filter device can comprise or consist of a fabric, wherein the fabric is preferably a microfabric. This results in particularly good filtering performance and a particularly advantageous suitability for arrangement of the filter device on the support structure, which saves space and costs. A filter device can provide particularly advantageous suitability for filtering by means of a particularly fine-mesh fabric (for example a stainless steel composite fabric). The filter device can be designed to separate particles which each have a diameter in the range of 10 to 100 μm, wherein the diameter is preferably an aerodynamic diameter. The filter device preferably comprises stainless steel. This allows the filter device to achieve good filtration on the one hand and to be easily arranged on the support structure on the other.In addition, the stainless steel gives the filter device a more resistant structure, which enables high filter performance over a longer period of time. The stainless steel can be incorporated into the filter device in various ways. It is preferred if the stainless steel forms a stainless steel mesh, with the filter device comprising or consisting of the stainless steel mesh.

[0016] The space defined by the support structure can be largely filled (i.e., at least 75%) by the catalyst. In other words, the support structure can be largely adapted to the volume defined by the catalyst. The filter unit is thus designed to be particularly compact and space-saving. It is preferred if the catalyst occupies at least 50%, particularly preferably at least 90%, of the space defined by the support structure.

[0017] The support structure can enclose the catalyst. This allows the catalyst to be arranged within the support structure in a particularly space-saving manner. The structure can also serve as a casing for the catalyst, thus protecting it from external mechanical stress (e.g., impacts).

[0018] The support structure can be elongated and / or tubular. It is preferred if the catalyst extends at least partially along the axis of the elongated and / or tubular design of the structure. This allows, in particular, the gas already filtered by the filter device to pass through the catalyst along a particularly long path. The axis of the elongated and / or tubular design of the support structure preferably extends through the outlet. This gives the filter unit a particularly compact design. It is preferred if the support structure has a width or diameter in the range from 50 to 200 mm, preferably from 70 to 150 mm, particularly preferably from 90 to 130 mm, wherein in one embodiment the width or diameter of the support structure is, for example, 120 mm. This gives the support structure and the filter device at least partially arranged in its space a particularly compact design.

[0019] The support structure can have a plurality of through-openings through which the gas, preferably in a state filtered by the filter device, can enter the space delimited by the support structure. The support structure therefore simultaneously provides an inlet through which the gas that has been filtered through the filter device and is subsequently to be treated by the catalyst can enter the space delimited by the support structure. The filter unit is thus designed to be particularly compact. In particular, the through-openings can be provided such that a gas can flow over the entire circumference of the support structure (i.e. all the way around) from outside the filter unit into the space delimited by the support structure and can thereby pass through the filter device. The support structure can have a side wall to which the filter device is attached, wherein the side wall has at least some of the through-openings.Optionally, the support structure can have a base from which the side wall extends. Thus, the space delimited by the support structure can be delimited on the one hand (laterally) by the side wall and on the other hand (from below) by the base, with the inner sides of these walls directed towards the filter device. As a result, the filter device is arranged particularly compactly relative to the support structure. The base can have a (further) part of the through-openings. Alternatively, it is also possible for the base to be designed such that it is impermeable to a gas to be treated with the filter unit and / or is designed as a lid, i.e. in particular has no through-opening. As a result, a gas can only enter the space delimited by the support structure from the side, namely via the side wall.

[0020] The support structure can comprise a mesh (wire mesh, twisted mesh, etc.), a fabric, and / or a grid to form at least some of the through-openings. This allows the through-openings to be provided particularly easily. Furthermore, it is conceivable, for example, that the corresponding structures of the support structure (the structures comprise, for example, rods and preferably run transversely to one another) serve to secure the filter device. If the support structure comprises a mesh, the support structure preferably forms a support mesh.Each through-opening can be defined by an outline, such as a polygonal (in particular square) or round (in particular elliptical or circular) outline, wherein the greatest possible distance between two points lying on the outline (in the case of a circular outline, this distance corresponds to the diameter) is in the range of 0.5 to 1.5 mm, preferably 0.75 to 1.25 mm. If the through-openings are each circular, each through-opening can have a diameter in the range of 0.5 to 1.5 mm, preferably 0.75 to 1.25 mm. Such distances or diameters allow a gas to flow particularly well through the support structure and thus the filter device arranged on the support structure and be filtered.

[0021] The support structure can be made of metal. This allows for easy manufacturing and provides particularly good rigidity, making the filter unit particularly robust against external influences (impacts, shocks, etc.).

[0022] The filter unit can further comprise an outlet line that provides the outlet. The outlet can thus be provided and maintained particularly easily. The outlet line also makes it easy to connect the outlet to other lines or the environment (namely, by extending the outlet into the environment). It is preferred if the outlet line is an outlet pipe.

[0023] The outlet line can have a flange, via which the outlet line is attached to the support structure, in particular to an edge of the support structure. This allows the outlet line to be easily provided in the filter unit, namely by simply placing the flange on the structure and then attaching it to it. The flange is preferably provided such that it (at least partially) delimits the space delimited by the support structure. This allows the filter unit to be further reduced in size. Alternatively or additionally, the side wall (or the aforementioned edge) of the support structure can define an opening that is at least partially covered by the flange. If the outlet line, including the flange, is attached to the support structure, the opening is preferably covered by the flange except for a point via which the gas treated with the catalyst flows from the space via the opening into the outlet or outlet line.

[0024] The outlet line, preferably the flange, can be attached to the support structure via a positive and / or non-positive connection. This allows the filter unit to be easily dismantled, for example by loosening the positive and / or non-positive connection with a tool or without tools; subsequently, the catalyst, for example, can be removed or pulled out of the space defined by the support structure. Such a connection between the outlet line and the support structure allows maintenance of the filter unit without completely interrupting operation, which means that, for example, access to the space of the support structure is possible while the filter device and the catalyst can still filter or treat the gas. The positive and / or non-positive connection preferably has a screw connection.By releasing the force-locking and / or form-locking connection, a component of the filter unit (support structure, catalyst, filter device, etc.) can also be easily replaced as such. The catalyst can preferably have a cylindrical or sleeve-shaped housing. This allows the catalyst to be provided in the form of a cartridge ("catalyst cartridge"). A catalyst filling can be arranged in the housing, wherein the catalyst filling preferably comprises granules and / or is at least partially spherical.

[0025] The housing of the catalyst can have a catalyst base and a catalyst side wall extending from the catalyst base. The catalyst base and the catalyst side wall thus preferably define a space in which the catalyst filling is arranged. It is preferred if the gas (filtered by the filter device) is fed to the catalyst via the catalyst base for

[0026] Treatment is possible. This makes it particularly easy to ensure that the gas to be treated passes through the catalyst along its entire length and is thereby treated. In a preferred embodiment, the gas can preferably only be fed to the catalyst via the catalyst base.

[0027] The catalyst side wall can run next to and / or parallel to a wall (e.g., the side wall) of the support structure. This allows the catalyst to be arranged in a particularly space-saving manner relative to the support structure, allowing the filter unit to be further reduced in size. Alternatively or additionally, the catalyst base can run next to and / or parallel to a (further) wall (e.g., the base) of the support structure. This also results in a particularly space-saving arrangement of the support structure and the catalyst relative to one another. The filter unit can further comprise a further filter device, such as, for example, a molecular sieve. By using the further filter device, (undesired) gases (such as, for example, CO2 or hydrofluoric acid vapors, which are produced during the combustion of plastics such as PTFE and its derivatives) can also be removed from the

[0028] The gas or gas mixture is removed, making the gas discharged from the filter unit via the outlet particularly pure. This allows the filter unit to be used, for example, in a ventilation system. The additional filter device can be provided downstream of the filter device and upstream of the catalyst, or within the catalyst, and / or arranged in the space defined by the support structure. The additional filter device is thus arranged particularly compactly in the filter unit.

[0029] According to a second aspect, the invention relates to a method for filtering and treating a gas, such as an exhaust gas. The method comprises the following (sequential) steps: providing a filter unit as described above; filtering the gas through the filter device of the filter unit; treating the filtered gas through the catalyst of the filter unit; and discharging the filtered and treated gas from the filter unit via the outlet of the filter unit.

[0030] The invention will now be described by way of example with reference to the figures, which illustrate a preferred embodiment of the invention. Figure 1 shows a schematic sectional view of a preferred embodiment of the filter unit according to the invention; and

[0031] Figure 2 is an enlarged detail of the filter unit shown in Figure 1, the detail showing a side wall of the support structure with the filter device arranged on the side wall.

[0032] Figure 1 shows a filter unit 1 according to a preferred embodiment. The filter unit 1 is designed to first filter and then treat a gas. The gas is produced, for example, as a byproduct in a process, such as an energy conversion process and / or a manufacturing process.

[0033] In particular, the gas can be exhaust gas, smoke, and / or air. The gas can, in particular, contain (harmful) media (particles, gases, etc.) that are to be removed from the gas or at least rendered harmless by the filter unit 1. The filter unit 1 has a filter device 2. The filter device 2 is provided to filter a gas, the flow of which is indicated in Figure 1 by the arrows 3. The filter device 2 is, in particular, designed to retain particles of a certain size, so that the gas flowing out of the filter device 2 contains fewer particles, such as fine dust, than the gas flowing into the filter device 2. It is preferred if the filter device 2 is designed to separate particles that each have a diameter in the range of 10 to 100 pm; the diameter is preferably an aerodynamic diameter.The particles filtered from the gas then collect on and / or in the filter 2, where they can then be removed.

[0034] The filter device 2 is not limited to a specific embodiment. The filter device 2 is preferably designed in a planar manner. This means in particular that the filter device 2 can have a constant thickness along its direction of extension to form the planar shape. Figure 2 shows an enlarged example of a preferred embodiment of the filter device 2. It can be seen that the filter device 2 can have or consist of several, in particular two, layers 21, 22. Several layers or a multi-layer structure of the filter device 2 are particularly advantageous in order to achieve high filter performance. The layers 21, 22 can have different filter finenesses. The first layer 21 can be provided downstream of the second layer 22 and also have a higher filter fineness than the second layer 22. This makes it possible to achieve a particularly high filter performance of the filter device 2.The first layer 21 can be a micro-fabric layer, for example, with a mesh size of 10 to 200 μm, preferably 10 to 100 μm, particularly preferably 25 to 50 μm. The second layer 22 can be a coarser separation mesh and / or have a coarser mesh size, preferably such that at least fine dust particles can be separated.

[0035] The filter device 2, in particular its layers 21, 22, can comprise or consist of a fabric. It is preferred if the layers 21, 22 each consist of a fabric. The fabric can be a microfabric. The microfabric preferably forms passage openings with a diameter of 10 to 100 μm each, preferably 25 to 50 μm. The filter device 2 is not limited to a specific material. The filter device 2 can be made of one material or of different materials. The filter device 2 preferably comprises stainless steel.

[0036] The filter unit 1 further comprises a catalyst 4. With respect to the flow of a gas that passes through the filter unit 1 for filtering and treatment, the catalyst 4 is arranged downstream of the filter device 2. As a result, the gas filtered by the filter device 2 (i.e., the gas flowing out of the filter device 2) can be treated with the catalyst 4. In Figure 1, the gas flowing out of the filter device 2 and subsequently flowing into the catalyst 4 is indicated by the arrow 5. The catalyst 4 treats the gas by converting certain media contained in the gas to be treated (for example, gaseous media) in such a way that they are not harmful, in particular not toxic, to the environment (living organisms, plants, ecosystems, etc.). If the gas filtered through the filter device 2, for example, still contains the gaseous product NO X , the catalyst 4 releases this NOX to non-toxic nitrogen (N2). Catalyst 4 thus performs a catalytic or adsorptive purification of the gas.

[0037] The catalyst 4 can have a preferably cylindrical or sleeve-shaped housing 41, in which a catalyst filling 40 is preferably provided. The housing 41 is preferably made of steel and / or another high-quality, resistant material. The catalyst filling 40 is designed to convert the harmful media present in the gas to be treated (pollutants such as combustion pollutants) into non-toxic substances (for example, CO2, H2O, and N2) by chemical conversion. Such a conversion can occur, for example, through oxidation or reduction. The catalyst filling 40 is preferably provided in the form of granules and / or spheres. In addition, the catalyst 4 can be configured to neutralize (e.g., as salt) and retain gases (HCl, SO2, etc.).The gases neutralized in this way are then retained in the catalyst 4, for example in the form of a salt or another, preferably solid substance, whereby they cannot escape into the environment. The catalyst 4 thus forms a so-called "chemical sponge." The housing 41 can have a catalyst base 42, which is preferably bowl-shaped. The gas preferably enters the catalyst 4 via the catalyst base 42 in order to treat this gas accordingly in the catalyst 4. For this purpose, the catalyst base 42 can be designed with several through-openings and / or as a sieve base. The catalyst base 42 can therefore be perforated. In particular, for advantageous entry of the gas to be treated into the catalyst 4, it can be provided that the catalyst base 42 is provided in the form of a (particularly coarse-meshed) net.The housing 41 preferably has a side wall 43 extending away from the catalyst base 42. Preferably, no gas enters the catalyst 4 via the side wall 43, so that gas can preferably only enter the catalyst 4 via the catalyst base 42. The side wall 43 preferably surrounds the catalyst filling 40 in a closed, circumferential manner. For example, the side wall 43 can form a cylinder or a tube.

[0038] The housing 41 may further comprise an upper part 44 through which the gas treated with the catalyst can escape from the catalyst 4. The upper part 44 is preferably connected to the catalyst base 42 via the side wall 43. The

[0039] Upper part 44 preferably has a plurality of through-openings through which the treated gas can flow out of the catalyst 4. It is preferred if the catalyst filling 40 extends between the catalyst base 42 and the upper part 44 and / or preferably completely fills a space defined between these parts 42, 44. The catalyst base 42, the side wall 43, and the upper part 44 preferably delimit a space in which the catalyst filling 40 is provided.

[0040] The filter unit 1 further has an outlet 6 through which the gas treated by the catalyst 4 can be discharged from the filter unit 1. The flow of both filtered and treated (and thus particularly pure) gas exiting the outlet 6 and thus from the filter unit 1 into the environment U is indicated in Figure 1 by the arrow 7. The outlet 6 is preferably provided such that the gas flowing out of the upper part 44 and treated by the catalyst 4 can enter the outlet 6 directly or indirectly. Indirect entry can occur, for example, if the gas flowing out of the upper part 44 enters the outlet 6 via an intermediate space formed between the upper part 44 and the outlet 6. It is preferred if the direction of flow of the gas flowing out of the upper part 44 is at least partially parallel to the direction of flow of the gas flowing out of the outlet 6 (see arrow 7).This means that the catalytic converter 4 and outlet 6 are arranged in a particularly space-saving manner.

[0041] The filter unit 1 may have an outlet line 61 having the outlet 6.

[0042] The outlet line 61 can serve as a connection to another line or can protrude into the environment U. The outlet line 61 can have a fastening area to which the other line can be attached. The outlet line 61 can be designed to establish a defined direction of flow of the gas exiting the outlet 6 and thus the filter unit i. Preferably, the outlet line 61 is an outlet pipe.

[0043] The filter unit 1 further comprises a support structure (i.e. a carrier structure) 8 on which at least the filter device 2 is arranged. The filter device 2 is therefore at least held by the support structure 8, so that the filter device 2 in particular has a defined position relative to the support structure 8 and thus to the catalyst 4. In particular, the filter device 2 is held captively by the support structure 8, so that in particular trouble-free operation of the filter device 2 within the filter unit 1 is possible. The filter device 2 is preferably fastened to the support structure 8, for example by means of a material bond. The fastening by means of a material bond can be effected by welding, preferably via a plurality of points and / or lines. The welding can be a nano-welding. In other embodiments, the filter device 2 can also be fastened to the support structure 8 by means of a force fit and / or a form fit.The support structure 8 defines or delimits a space 81 in which the catalyst 4 is at least partially arranged. As a result, the catalyst 4 is integrated within the filter unit 1 and is thus arranged in a particularly space-saving manner. The support structure 8 can have a side wall 82 to which the filter device 2 is fastened and which laterally delimits the space 81. The support structure 8 can further have a base 83 from which the side wall 82 extends. The base 83 preferably delimits the space 81 from below, i.e., the space 81 preferably extends between the base 83 and the outlet 6. The side wall 82 preferably defines an opening 84 via which the space 81 can be accessed. For example, the catalyst 4 can be at least partially arranged in the space 81 via the opening 84.When the catalytic converter 4 is in its assembled state, the catalytic converter 4 can extend through the opening 84 and thus protrude beyond the side wall 82 when viewed from the latter. A part of the catalytic converter 4, namely the part protruding from the opening 84, can thus be provided outside the space 81, whereas the remaining part of the catalytic converter 4 is arranged completely in the space 81. Alternatively, it can also be possible for the catalytic converter 4 to be arranged entirely - that is to say completely - in the space 81. The support structure 8 preferably surrounds the catalytic converter 4 in a closed manner. For this purpose, the structure 8 can be at least partially designed in the form of a tube and / or the side wall 82 can run around the catalytic converter 4 in a closed manner (seen in a sectional view). As can be seen in Figure 1, the support structure 8 can be elongated and thus form a correspondingly elongated space 81 in which the

[0044] Catalyst 4 can extend elongately in a corresponding manner. The structure 8 can have a round (circular, elliptical, etc.) or polygonal (quadrilateral, rectangular, square, etc.) cross-section. The width or diameter of the support structure 8 can range from 50 to 200 mm, preferably from 70 to 150 mm, particularly preferably from 90 to 130 mm. In a particularly preferred embodiment, the support structure 8 has a width or diameter of 120 mm + / - 10 mm.

[0045] The catalyst 4 can be arranged in the space 81 such that the catalyst 4 (in particular the volume defined by the catalyst housing 41)

[0046] Most of the space 81 fills, preferably at least 75%, particularly preferably at least 90%. If the catalyst 4 is at least partially arranged in the space 81, an intermediate space 81.1, 81.2 can be formed between the catalyst 4 and the support structure 8. The intermediate space can have a first intermediate space 81.1 and a second intermediate space 81.2. The first intermediate space 81.1 can be annular, for example in the form of a ring having a polygonal or round (preferably circular) shape. The first intermediate space 81.1 is laterally delimited preferably at least by the side wall 43 (and preferably by a lateral part of the base 42) of the catalyst 4 and the side wall 82 of the support structure 8. The second intermediate space 81.2 can be a

[0047] Have a shape that does not correspond to a ring. The intermediate space 81.2 preferably extends between the base 42 of the catalyst 4 and the base 83 of the structure 8. In other words, the intermediate space 81.2 can be bounded at the top by the base 42 and at the bottom by the base 83. The intermediate spaces 81.1, 81.2 are preferably fluidically connected to one another.

[0048] As can be seen in Figure 1, the catalyst side wall 43 can run next to and parallel to the side wall 82 of the support structure 8, thereby preferably forming the intermediate space 81.1. Alternatively, however, it can also be provided that the intermediate space 81.1 is formed by the catalyst side wall 43 running next to the side wall 82, but not parallel, but rather, for example, obliquely to it. As can also be seen in Figure 1, the catalyst base 42 can run next to and parallel to the base 83 of the support structure 8, preferably in order to form the intermediate space 81.2. The intermediate space 81.2 can, however, also be formed by the catalyst base 42 running next to the base 83, but not parallel, but rather, for example, obliquely to it. The outlet line 61, which has the outlet 6, can have a flange 62, via which the outlet line 61 and thus the outlet 6 is fastened to the support structure 8.The fastening is preferably achieved via a positive and / or non-positive connection, for example, a screw connection or a quick-action coupling. The fastening is preferably achieved via a fastening means 63, which preferably provides the positive and / or non-positive connection between the two.

[0049] Flange 62 and support structure 8, for example the side wall 82 (in particular the free end of the side wall 82 which defines the opening 84). The fastening means 63 is preferably designed to fasten the flange 62 to the support structure 8 with a tool (screwdriver, etc.) or without tools (e.g. in that the fastening means 63 has a lever for selectively releasing or providing the connection to the support structure 8). Preferably, the fastening means 63 has: a first region at which the flange 62 is provided (preferably detachably, for example via force and / or form fit, in particular via a screw connection), and a second region at which the support structure 8 is provided via its side wall 82 (preferably non-detachably, for example via a material bond, in particular via a welded connection).The fastening means 63 can have a region to which the catalytic converter 4, preferably its side wall 43, is arranged and preferably fastened, in particular via force, form, and / or material connection. This region can be an inwardly directed region (i.e., e.g., directed in the direction of the longitudinal axis of the catalytic converter 4).

[0050] The flange 62 is preferably provided such that it delimits the space 81, preferably at an upper end of the support structure 8, and / or partially covers the opening 84, so that exit from the opening 84 into the environment U can only occur via the outlet 6. The flange 62 preferably has, on its side (inner side) 64 facing the space 81, an area to which the catalytic converter 4 (preferably via its side wall 43) can be provided and, for example, also fastened, in particular via a force-fit, form-fit and / or material fit. In particular, the catalytic converter 4 can be inserted into the side 64. Alternatively or additionally, the catalytic converter 4 (for example via its side wall 43) can be provided on the fastening means 63 and preferably fastened, in particular via a force-fit, form-fit and / or material fit.By loosening and subsequently removing the flange 62 from the support structure 8, it may be possible, in particular, to simultaneously remove the catalytic converter 4 from the space 81. Alternatively, however, it may also be provided that by removing the flange 62, the catalytic converter 4 continues to be secured with respect to the support structure 8 (for example, via the fastening means 63), in order to thereby, for example, carry out maintenance (repair, removal, etc.) on the catalytic converter 4.

[0051] It is preferred if the filter device 2 is arranged outside the space 81 delimited by the support structure 8, as shown by way of example in Figures 1 and 2. This allows the filter device 2 to be easily serviced (cleaned, replaced, etc.) without the filter unit 1 having to be dismantled, i.e., in particular, without the outlet 6 and / or catalyst 4 having to be moved relative to the support structure 8 in order to gain access to the filter device 2. Furthermore, the filter device 2 can thus be easily provided in a manufacturing process, for example, by wrapping the support structure 8 around the filter device 2.

[0052] The gas flowing out of the filter device 2 and thus filtered can flow in different ways toward the downstream catalyst 4. One possibility for this is shown in Figures 1 and 2. It can be seen that the support structure 8 has a plurality of through-openings 85 through which the gas, filtered by the filter device 2, can enter the space 81 delimited by the support structure 8. The through-openings 85 are preferably provided such that they open into the first intermediate space 81.1 and / or the second intermediate space 81.2. The side wall 82 can have the through-openings 85, for example by distributing the latter evenly over the surface (preferably the entire surface) of the side wall 82. The base 83 preferably has no through-openings 85 and is therefore impermeable to a gas and / or is designed as a cover.In another embodiment, the base 83 may also have some of the through-openings 85. Then, the filter device 2 is preferably also arranged on the base 83 and preferably attached thereto.

[0053] The through-openings 85 can be provided in different ways. As shown in Figures 1 and 2, the support structure 8 can, for example, have a mesh, a fabric, and / or a grid (grid) to form at least part of the through-openings 85. It can be provided that the side wall 82 forms the mesh, the fabric, and / or the grid. As shown in Figure 2, the structures that form the mesh, the fabric, and / or the grid—in particular (linear) structures that run transversely to one another—can have regions to which the filter device 2 is attached. For example, it is conceivable for these structures to have the linear or point-shaped contact regions between the support structure 8 and the filter device 2, via which the filter device 2 is attached to the support structure 8 by means of a material bond.

[0054] The through-openings 85 preferably each have a defined size. For example, the greatest possible distance between two points lying on a contour (polygonal, circular, etc.) delimiting a through-opening 85 is in the range of 0.5 to 1.5 mm, preferably 0.75 to 1.25 mm. If the through-openings 85 are each circular, their respective diameter is preferably in a range of 0.5 to 1.5 mm, preferably 0.75 to 1.25 mm. The support structure 8 is not limited to a specific material. The support structure 8 can be made of only one material or of different materials. The support structure 8 is preferably made of metal. The support structure 8 can be manufactured, for example, by attaching the base 83 to the side wall 82 via a material bond, such as welding.

[0055] The filter unit 1 can further comprise a further filter device (not shown), such as a molecular sieve, which is preferably provided downstream of the filter device 2 and upstream of the catalyst 4, for example in the space 81, or in the catalyst 4, for example in the space for the catalyst filling 40. Alternatively, however, it can also be provided that the further filter device is provided downstream of the catalyst 4. The gas flowing out of the outlet 6 is thus, on the one hand, filtered by the filter device 2 and treated by the catalyst 4 and, on the other hand, further filtered by the further filter device. In the filter stage provided by the further filter device, for example, certain gases (e.g. CO2) can be filtered.

[0056] With the embodiment of the filter unit 1 shown in Figures 1 and 2, a gas (for example, an exhaust gas) can be filtered and treated as follows. A gas first enters the filter device 2 (see arrows 3), where it is filtered, and certain particles (fine dust, etc.) are separated and retained from the gas (“sieve effect”). Subsequently, in the filtered and thus pre-cleaned state – in this state the gas may still contain gaseous products such as nitrogen (N2) – the gas enters the intermediate space 81.1 and / or the intermediate space 81.2 via the through-openings 85. The gas that has entered the intermediate space 81.1 then flows along the side walls 43, 82 towards the catalyst inlet or catalyst base 42, where it enters the catalyst 4 for treatment. The filtered gas, which enters the intermediate space 81.1 via the through-openings 85,2 can enter the catalytic converter 4 directly, namely only via a path running through the intermediate space 81.2. Once it has entered the catalytic converter 4, the gas preferably passes through the catalytic converter 4 along its entire length in order to be treated over the largest possible surface area, i.e. to convert certain media (pollutants such as NOx) in the gas filtered through the filter device 2 as completely as possible. The treated gas then flows out of the catalytic converter 4, for example via the upper part 44, and enters the environment U via the outlet 6. There, the gas is then both filtered and treated and thus poses no or at least a significantly reduced danger to the environment U.

[0057] The cleaning of the filter device 2 can be carried out by increasing the pressure in the space 81. The resulting overpressure causes a pressure equalization between the space 81 and the outside to the side of the

[0058] Filter device 2, whereby the particles collected in the filter device 2 can be removed from the filter device 2. The increase in pressure in the space 81 preferably takes place via the outlet 6 or an inlet (not shown; e.g., the flange 62 comprises the inlet), for example by supplying a fluid (ambient air, etc.) to the space 81. In one embodiment, the filter unit 1 has a flow device for supplying the fluid to the space 81 and thus increasing the pressure therein.

[0059] The invention is not limited to the features described above; in particular, the features described above can be combined with one another in any desired manner.

Claims

Claims 1. Filter unit (i) for filtering and treating a gas such as an exhaust gas, comprising: - a filter device (2) for filtering a gas, a catalyst (4) for treating the gas filtered by the filter device (2), an outlet (6) via which the gas treated with the catalyst (4) can be discharged from the filter unit (1), and - a support structure (8) on which the filter device (2) is arranged, wherein the support structure (8) delimits a space (81) in which the catalyst (4) is at least partially arranged.

2. Filter unit (1) according to claim 1, wherein the filter device (2) is arranged at least partially outside the space (81) delimited by the support structure (8).

3. Filter unit (1) according to claim 1 or 2, wherein the filter device (2) is attached to the support structure (8).

4. Filter unit (1) according to one of the preceding claims, wherein the filter device (2) is attached to the support structure (8) by means of a material connection, such as welding.

5. Filter unit (1) according to one of the preceding claims, wherein the Filter device (2) is designed in a planar manner and / or has one or more layers (21, 22), wherein preferably a first layer (21) has a higher filter fineness than a second layer (22), wherein the first layer (21) is preferably provided downstream of the second layer (22).

6. Filter unit (1) according to one of the preceding claims, wherein the filter device (2) forms a cylindrical and / or tubular shape.

7. Filter unit (1) according to one of the preceding claims, wherein the filter device (2) comprises or consists of a fabric, wherein the fabric is preferably a microfabric.

8. Filter unit (1) according to one of the preceding claims, wherein the filter device (2) is designed to separate particles each having a diameter in the range of 10 to 100 pm, wherein the diameter is preferably an aerodynamic diameter.

9. Filter unit (1) according to one of the preceding claims, wherein the filter device (2) comprises stainless steel.

10. Filter unit (1) according to one of the preceding claims, wherein the space (81) delimited by the support structure (8) is largely filled by the catalyst (4), wherein the catalyst (4) preferably occupies at least 75%, particularly preferably at least 90% of the space (81) delimited by the support structure (8).

11. Filter unit (1) according to one of the preceding claims, wherein the Support structure (8) surrounds the catalyst (4) in a closed manner.

12. Filter unit (1) according to one of the preceding claims, wherein the support structure (8) is elongated and / or tubular.

13. Filter unit (1) according to one of the preceding claims, wherein the support structure (8) has a width or a diameter in the range from 50 to 200 mm, preferably from 70 to 150 mm, particularly preferably from 90 to 130 mm, wherein the width or the diameter of the support structure (8) is, for example, 120 mm.

14. Filter unit (1) according to one of the preceding claims, wherein the support structure (8) has a plurality of through-openings (85) through which the gas, preferably in a state filtered by the filter device (2), can enter the space (81) delimited by the support structure (8).

15. Filter unit (1) according to claim 14, wherein the support structure (8) has a side wall (82) to which the filter device (2) is fastened, wherein the side wall (82) has at least some of the through openings (85), wherein the support structure (8) preferably has a base (83) from which the side wall (82) extends, wherein preferably the base (83) has some of the through openings (85) or is impermeable to a gas to be treated with the filter unit (1) and / or is designed as a cover. Filter unit (1) according to claim 14 or 15, wherein the support structure (8) comprises a mesh, a fabric and / or a grid to form at least some of the through-openings (85). Filter unit (1) according to one of claims 14 to 16, wherein each through-opening (85) is delimited by an outline, such as a polygonal or round outline, wherein the greatest possible distance between two points lying on the outline is in the range of 0.5 to 1.5 mm, preferably 0.75 to 1.25 mm, or wherein each through-opening (85) has a diameter in the range of 0.5 to 1.5 mm, preferably 0.75 to 1.25 mm. Filter unit (1) according to one of the preceding claims, wherein the support structure (8) is made of metal. Filter unit (1) according to one of the preceding claims, further comprising an outlet line (61) comprising the outlet (6), wherein the outlet line (61) is preferably an outlet pipe. Filter unit (1) according to claim 19, wherein the outlet line (61) has a flange (62) via which the outlet line (61) is fastened to the support structure (8), wherein the flange (62) preferably delimits the space (81) delimited by the support structure (8), and / or wherein preferably the side wall (82) of the support structure (8) defines an opening (84) which is at least partially covered by the flange (62). Filter unit (1) according to claim 19 or 20, wherein the outlet line (61), preferably the flange (62), is fastened to the support structure (8) via a positive and / or non-positive connection, wherein the positive and / or non-positive connection preferably comprises a screw connection.Filter unit (1) according to one of the preceding claims, wherein the catalyst (4) has a preferably cylindrical or sleeve-shaped housing (41), and wherein the catalyst (4) preferably has a catalyst filling (40) arranged in the housing (41), wherein the catalyst filling (40) preferably comprises a granulate and / or is provided at least partially spherically. Filter unit (i) according to claim 22, wherein the housing (41) has a catalyst base (42) and a catalyst side wall (43) extending from the catalyst base (42), wherein the gas can preferably be fed to the catalyst (4) for treatment via the catalyst base (42). Filter unit (1) according to claim 23, wherein the catalyst side wall (43) runs adjacent to and / or parallel to a wall of the support structure (8), wherein the wall is, for example, the side wall (82) of the support structure (8), and / or wherein the catalyst base (42) runs adjacent to and / or parallel to a further wall of the support structure (8), wherein the further wall is, for example, the base (83) of the support structure.Filter unit (1) according to one of the preceding claims, further comprising a further filter device such as a molecular sieve, wherein the further filter device is preferably provided downstream of the filter device (2) and upstream of the catalyst (4) or in the catalyst (4) and / or arranged in the space (81) delimited by the support structure (8). A method for filtering and treating a gas such as an exhaust gas, comprising the following steps: Providing a filter unit (1) according to one of the preceding claims, - filtering the gas through the filter device (2) of the filter unit (1), Treating the filtered gas through the catalyst (4) of the filter unit (1) and Discharge of the filtered and treated gas from the filter unit (1) via the outlet (6) of the filter unit (1).

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