Filter unit

Abstract

The invention relates to a filter unit (1) for filtering and treating gases, such as exhaust gases. The filter unit (1) is provided with a filter device (2) for filtering a gas, a catalyst (4) for treating the gas filtered by the filter device (2), an outlet (6) for discharging the gas treated by the catalyst (4) from the filter unit (1), and a support structure (8) provided with the filter device (2), the support structure (8) defining a space (81), the catalyst (4) is arranged at least partially within the space. The invention also relates to a method for filtering and treating gases using a filter unit (1) according to the invention.

Description

Technical Field

[0001] The invention relates to a filter unit and a method for filtering and treating gases such as exhaust gases. Background Art

[0002] In many processes, by-products are generated that may have adverse effects on the environment (humans, animals, plants, ecosystems, etc.). In particular, in energy conversion processes or production processes, unwanted by-products (fine particles and / or toxic components such as nitrogen oxides (NOx), sulfur dioxide (SO2), hydrogen chloride (HCl), etc.) may be released into the environment in the exhaust gas, which can have a negative impact on the health of organisms and the climate.

[0003] Therefore, efforts are made to avoid the release of harmful, often toxic by-products (pollutants) into the environment during these processes. However, this is not an easy task, since the equipment required for the individual processes often requires complex modifications or even redevelopment in order to reduce the release of pollutants into the environment via the exhaust gases. If the processes are already equipped with corresponding devices to reduce the release of pollutants into the environment, the failure of these devices can lead to high maintenance costs as well as a complete interruption of the entire process, which can have significant economic consequences (production interruption, interruption of energy conversion, etc.). Summary of the invention

[0004] It was therefore an object of the present invention to overcome the above-mentioned disadvantages and, in particular, to reduce the release of undesirable by-products in a simpler manner during technical or chemical processes.

[0005] This object is achieved by the subject matter of the independent claim. Advantageous developments are the subject matter of the dependent claims.

[0006] According to a first aspect, the present invention relates to a filter unit for filtering and treating gases such as exhaust gases, etc. The filter unit comprises: a filter device for filtering the gas; a catalyst for treating the gas filtered by the filter device; an outlet through which the gas treated by the catalyst can be discharged from the filter unit; and a support structure on which the filter device is arranged, wherein the support structure defines a space in which the catalyst is at least partially arranged.

[0007] Thus, the filter unit provides a two-stage double purification in a single device, i.e., filtering the gas in a first stage (i.e., separating and retaining specific particles, such as fine particles transported by the gas), and treating the filtered gas in a second stage with a catalyst, thereby further reducing harmful (e.g., gaseous) media in the gas. Thus, equipment or devices such as energy conversion devices or components (power plants, combustion devices, biogas plants, heaters using renewable raw materials (e.g., wood pellets), natural gas devices, chimneys, etc.) or manufacturing devices (e.g., for cement production) can be easily equipped or retrofitted with the filter unit to significantly reduce the release of particularly harmful media (fine particles, toxic components such as nitrogen oxides (NOx), sulfur dioxide (SO2), hydrogen chloride (HCl), etc.) into the environment during the respective process. In particular, through the two-stage purification of the filter unit, the gas can be purified to be almost free of fine particles and toxic components, and even cleaner than ambient air.

[0008] Furthermore, by arranging the catalyst at least partially in the space defined by the support structure and arranging the filter device on the support structure, a very compact filter unit is provided. The filter unit can thus be easily arranged at a desired location (e.g. at an exhaust gas outlet such as a chimney). Moreover, due to its compact design, the filter unit can even be used in places that are difficult to reach, thereby greatly simplifying the reduction of particles (in particular fine particles) and other harmful (e.g. gaseous) components in all process steps.

[0009] The filter device can be arranged at least partially outside the space defined by the support structure. In this way, maintenance (replacement, cleaning, etc.) of the filter device can be carried out particularly simply, since in particular it is not necessary to enter the space defined by the support structure to maintain the filter device. The filter device can also be arranged simply during the manufacture of the filter unit, for example by winding the support structure around the filter device.

[0010] Preferably, the filter device is fixed to the support structure. This ensures that the filter device remains in a defined position relative to the support structure when subjected to mechanical loads (eg due to airflow, transport or other effects).

[0011] The filter device can be fastened to the support structure by material connection, for example welding (preferably nano-welding and / or sintering welding). In this way, the filter device can be fastened to the support structure particularly easily, since such fastening can be achieved, for example, via the contact points between the support structure and the filter device. In addition, such a fastening method can be automated particularly well, thus saving time and costs.

[0012] The filter device can be designed in a planar manner and / or have one or more layers. In this way, the filter device takes up particularly little space in the filter unit and can be easily arranged therein. In addition, the multi-layer structure makes it easy to set different functions (e.g. filter levels) for the filter device. Preferably, the first layer of the filter device has a higher filtering accuracy than the second layer of the filter device, wherein the first layer is preferably arranged downstream of the second layer. In this way, the filter device can achieve a particularly good filtering effect.

[0013] The filter device is preferably cylindrical and / or tubular. That is, the filter device may have one or more layers (eg, by being arranged on or wrapped around a support structure) that can form a shape corresponding to a cylinder or a tube.

[0014] The filter device can have a fabric or consist of a fabric, wherein the fabric is preferably a microfabric. This can achieve particularly good filter performance and is particularly suitable for arranging the filter device on a support structure, thereby saving space and costs. The filter device can provide particularly advantageous filter suitability by means of a particularly fine fabric, such as a stainless steel composite fabric.

[0015] The filter device may be designed to separate particles having a diameter in the range of 10 to 100 micrometers, wherein the diameter is preferably the aerodynamic diameter.

[0016] Preferably, the filter device contains stainless steel. In this way, the filter device can achieve a good filtering effect on the one hand and can be easily arranged on the support structure on the other hand. In addition, the stainless steel gives the filter device a more resistant structure, so that in particular it is possible to maintain a high filtering performance for a longer time. The stainless steel can be arranged in the filter device in different ways. Preferably, the stainless steel forms a stainless steel fabric, wherein the filter device comprises or consists of the stainless steel fabric.

[0017] The space delimited by the support structure can be filled to a large extent, i.e. at least 75%, by the catalyst. In other words, the support structure can be adapted to a large extent to the volume delimiting the catalyst. The design of the filter unit is thus particularly compact and space-saving. Preferably, the catalyst occupies at least 50%, particularly preferably at least 90%, of the space delimited by the support structure.

[0018] The support structure can enclose the catalytic converter in a closed manner. The arrangement of the catalytic converter in the support structure is thus particularly space-saving. In addition, the structure can thus serve as a housing for the catalytic converter, thereby, for example, also protecting the catalytic converter from external mechanical stresses (eg impacts).

[0019] The support structure can be designed to be elongated and / or tubular. In this case, it is preferred that the catalyst extends at least partially along the axis of the elongated and / or tubular design of the structure. As a result, in particular the gas that has been filtered by the filter device can pass through the catalyst along a particularly long path. Preferably, the axis of the elongated and / or tubular design of the support structure extends through the outlet. As a result, the design of the filter unit is particularly compact.

[0020] Preferably, the support structure has a width or diameter in the range of 50 to 200 mm, preferably 70 to 150 mm, particularly preferably 90 to 130 mm, wherein in one embodiment the width or diameter of the support structure is, for example, 120 mm. As a result, the design of the support structure and the filter device at least partially arranged in the space thereof is particularly compact.

[0021] The support structure can have a plurality of through-holes 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 thus simultaneously provides an inlet through which the gas, which has been filtered by 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-holes can be arranged so that the gas can flow from the outside of the filter unit around the entire circumference of the support structure (i.e. all-round) into the space delimited by the support structure and can pass through the filter device.

[0022] The supporting structure may have a side wall, to which the filter device is fixed, wherein the side wall has at least a portion of the through holes. Alternatively, the supporting structure may have a bottom, from which the side wall extends. Therefore, the space defined by the supporting structure is defined by the side wall on the one hand (at the side) and by the bottom on the other hand (from below), wherein the inner side of these walls faces the filter device. Thus, the arrangement of the filter device relative to the supporting structure is particularly compact. The bottom may have (another part) of the through holes. However, alternatively, the bottom may also be designed to be impermeable to the gas to be processed by the filter unit and / or to be designed as a cover, i.e., particularly without through holes. Thus, the gas can only enter the space defined by the supporting structure from the side, i.e., through the side wall.

[0023] The support structure can have a grid (wire grid, woven grid, etc.), a fabric and / or a grid to form at least a portion of the through-holes. Thus, the through-holes can be provided particularly easily. In addition, for example, it is conceivable that corresponding structures of the support structure (these structures, for example, have rods and preferably extend crosswise to each other) are used to fix the filter device. If the support structure has a grid, the support structure preferably forms a support grid.

[0024] Each through hole can be delimited by a contour such as a polygon (especially a quadrilateral) or a circle (especially an ellipse or a circle), wherein the maximum distance between two points located on the contour (in the case of a circular contour, 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 holes are each designed as a circle, each through hole can have a diameter in the range of 0.5 to 1.5 mm, preferably 0.75 to 1.25 mm. With such distances or diameters, the gas can flow particularly well through the support structure and the filter device arranged on the support structure and be filtered.

[0025] The support structure can be made of metal. As a result, the support structure can be easily produced and offers particularly good rigidity, so that in particular the filter unit is very robust, especially against external effects (impacts, shocks, etc.).

[0026] The filter unit can also have an outlet conduit, which has an outlet. Therefore, the outlet can be particularly easily arranged and maintained. In addition, the outlet can be easily connected to other pipelines or the environment (i.e., by making the outlet extend into the environment) through the outlet conduit. Preferably, the outlet conduit is an outlet pipe.

[0027] The outlet duct may have a flange, by which the outlet duct is fixed to the supporting structure, in particular to the edge of the supporting structure. Thus, the outlet duct can be easily arranged in the filter unit, namely by merely arranging the flange on the structure and then fixing it to the structure. The flange is preferably arranged so that it (at least partially) delimits the space delimited by the supporting structure. Thus, the size of the filter unit can be further reduced. Alternatively or additionally, the side wall (or the aforementioned edge) of the supporting structure can define an opening, which is at least partially covered by the flange. When the outlet duct with a flange is fixed to the supporting structure, preferably the opening is covered by the flange except for one position, through which the gas treated by the catalyst flows from the space through the opening into the outlet or the outlet duct.

[0028] The outlet pipe (preferably a flange) can be fixed to the support structure by a form-fitting and / or force-fitting connection. As a result, the filter unit can be easily disassembled, for example by releasing the form-fitting and / or force-fitting connection with or without tools; subsequently, for example, the catalyst can be removed or pulled out of the space delimited by the support structure. By means of this connection between the outlet pipe and the support structure, the filter unit can be maintained without completely interrupting operation, which means that, for example, the space of the support structure can be accessed while the gas can still be filtered or treated by the filter device and the catalyst. The form-fitting and / or force-fitting connection preferably has a threaded connection. By releasing the force-fitting and / or form-fitting connection, it is also possible for a component of the filter unit (support structure, catalyst, filter device, etc.) to be easily replaced as a whole.

[0029] The catalyst can have a preferably cylindrical or sleeve-shaped housing. Thus, the catalyst can be arranged in the form of a box ("catalyst box"). A catalyst filling can be arranged in the housing, wherein the catalyst filling preferably has a granular shape and / or is at least partially arranged in a spherical shape.

[0030] The housing of the catalyst can have a catalyst bottom and a catalyst side wall extending from the catalyst bottom. The catalyst bottom and the catalyst side wall thus preferably define a space in which the catalyst filling is arranged. Preferably, the gas (filtered by the filter device) can be conveyed to the catalyst for treatment via the catalyst bottom. This makes it particularly easy to ensure that the gas to be treated flows along the entire length of the catalyst and is thus treated. In a preferred embodiment, the gas is preferably conveyed to the catalyst only via the catalyst bottom.

[0031] The catalyst side wall can extend adjacent to and / or parallel to a wall of the support structure (e.g. a side wall). As a result, the arrangement of the catalyst relative to the support structure is particularly space-saving, so that the size of the filter unit can be further reduced. Alternatively or additionally, the catalyst bottom can extend adjacent to and / or parallel to another wall of the support structure (e.g. the bottom). As a result, a particularly space-saving arrangement of the support structure and the catalyst relative to each other can also be achieved.

[0032] The filter unit can also have a further filter device, for example a molecular sieve. By using the further filter device, (unwanted) gases (for example carbon dioxide (CO2) or hydrofluoric acid vapors produced when plastics such as polytetrafluoroethylene (PTFE) and its derivatives are burned) can also be removed from the gas or gas mixture, so that the gas discharged from the outlet through the filter unit is particularly pure. Therefore, the filter unit can be used, for example, in a ventilation system. The further filter device can be arranged downstream of the filter device and upstream of the catalyst, or in the catalyst and / or in the space defined by the support structure. Therefore, the arrangement of the further filter device in the filter unit is particularly compact.

[0033] According to a second aspect, the invention relates to a method for filtering and treating a gas such as exhaust gas. The method comprises the following steps (performed in sequence): providing a filter unit as described above; filtering the gas by a filter device of the filter unit; treating the filtered gas by a catalyst of the filter unit; and discharging the filtered and treated gas from the filter unit through an outlet of the filter unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention will be described exemplarily below with reference to the accompanying drawings, in which preferred embodiments of the present invention are shown. In the drawings:

[0035] Figure 1 shows a schematic cross-sectional view of a preferred embodiment of a filter unit according to the present invention;

[0036] Figure 2 Shows Figure 1 An enlarged detail of the filter unit is shown, wherein the detail shows the side walls of the support structure and the filter device arranged on the side walls. DETAILED DESCRIPTION

[0037] Figure 1 A filter unit 1 according to a preferred embodiment is shown. The filter unit 1 is used to first filter a gas and then treat it. The gas is produced, for example, as a by-product in a process, which can be, for example, an energy conversion process and / or a manufacturing process. In particular, the gas can be exhaust gas, smoke and / or air. The gas can contain (harmful) media (particles, gases, etc.) which should be removed from the gas or at least rendered harmless by the filter unit 1.

[0038] The filter unit 1 has a filter device 2. The filter device 2 is used to filter the gas. Figure 13. The filter device 2 is particularly 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 particles, than the gas flowing into the filter device 2. Preferably, the filter device 2 is designed to separate particles with a diameter in the range of 10 to 100 micrometers, which diameter is preferably the aerodynamic diameter. The particles filtered out of the gas are then collected on and / or in the filter device 2, where they can be removed.

[0039] The filter device 2 is not limited to a specific configuration. Preferably, the filter device 2 is of planar configuration. This means in particular that the filter device 2 can have a constant thickness along its extension direction to form a planar shape. Figure 2 A preferred configuration of the filter device 2 is exemplarily shown in an enlarged scale. It can be seen that the filter device 2 can have multiple layers, in particular two layers 21, 22, or be composed of these layers. The filter device 2 having a multi-layer or multi-layer structure is particularly conducive to achieving high filtering performance. The layers 21 and 22 can have different filtering precisions. The first layer 21 can be arranged downstream of the second layer 22 and has a higher filtering precision than the second layer 22. Thus, the filter device 2 can achieve particularly high filtering performance. The first layer 21 can be a micro-fabric layer, for example, with a mesh size of 10 to 200 microns, preferably 10 to 100 microns, and particularly preferably 25 to 50 microns. The second layer 22 can be a coarser separation grid and / or have a larger mesh size, preferably arranged in a manner that at least fine particles can be separated.

[0040] The filter 2, in particular its layers 21, 22, can have a fabric or consist of a fabric. Preferably, the layers 21, 22 are each composed of a fabric. The fabric can be a microfabric. The microfabric preferably forms through holes with a diameter of 10 to 100 microns, preferably 25 to 50 microns. The filter 2 is not limited to a specific material. The filter 2 can be made of one material or different materials. Preferably, the filter 2 contains stainless steel.

[0041] The filter unit 1 also has a catalyst 4. The catalyst 4 is arranged downstream of the filter device 2 relative to the flow of the gas filtered and treated by the filter unit 1. Thus, the gas filtered by the filter device 2 (i.e., the gas flowing out of the filter device 2) can be treated by the catalyst 4. Figure 1, the gas flowing out of the filter device 2 and then flowing into the catalyst 4 is indicated by arrow 5. The catalyst 4 treats the gas by converting a specific (e.g., gaseous) medium contained in the gas to be treated into a substance that is harmless to the environment (organisms, plants, ecosystems, etc.), especially non-toxic. For example, if the gas filtered by the filter device 2 still contains gaseous products NOx, the catalyst 4 converts the NOx into non-toxic nitrogen (N2). Therefore, the gas is catalytically or adsorbed and purified by the catalyst 4.

[0042] The catalyst 4 can have a preferably cylindrical or sleeve-shaped housing 41, in which a catalyst filling 40 is preferably arranged. The housing 41 is preferably made of steel and / or other high-quality resistant materials. The catalyst filling 40 is designed to convert harmful media (e.g., pollutants such as combustion pollutants) present in the gas to be treated into non-toxic substances (e.g., carbon dioxide (CO2), water (H2O) and nitrogen (N2)) by chemical conversion. Such a conversion can be carried out, for example, by oxidation or reduction. The catalyst filling 40 is preferably arranged in a granular form and / or a spherical form. In addition, the catalyst 4 can be arranged to neutralize (e.g., as a salt) and trap gases (HCl, SO2, etc.). The gas thus neutralized is then retained in the catalyst 4, for example, in the form of salt or other preferably solid substances, so that they do not leak into the environment. The catalyst 4 thus forms a so-called "chemical sponge".

[0043] The housing 41 may have a catalyst bottom 42, which is preferably in a shell-like structure. The gas preferably enters the catalyst 4 through the catalyst bottom 42 so that the gas is treated accordingly in the catalyst 4. To this end, the catalyst bottom 42 may be provided with a plurality of through holes and / or configured as a sieve plate. Therefore, the catalyst bottom 42 may be perforated. In particular, in order to facilitate the entry of the gas to be treated into the catalyst 4, the catalyst bottom 42 may be configured as a (particularly coarse-mesh) mesh form. The housing 41 preferably has a side wall 43 extending from the catalyst bottom 42. The gas preferably does not enter the catalyst 4 through the side wall 43, so that the gas preferably enters the catalyst 4 only through the catalyst bottom 42. The side wall 43 preferably surrounds the catalyst filling 40 in a closed manner. For example, the side wall 43 may form a cylinder or a tube.

[0044] The housing 41 may also have a top 44 through which the gas treated by the catalyst can be discharged from the catalyst 4. The top 44 is preferably connected to the catalyst bottom 42 via a side wall 43. The top 44 is preferably provided with a plurality of through holes through which the treated gas can flow out of the catalyst 4. Preferably, the catalyst filling 40 extends between the catalyst bottom 42 and the top 44, and / or preferably completely fills the space defined by these two parts (42, 44). The catalyst bottom 42, the side wall 43 and the top 44 preferably define a space in which the catalyst filling 40 is arranged.

[0045] The filter unit 1 also has an outlet 6 through which the gas treated by the catalytic converter 4 can be discharged from the filter unit 1. The filtered and treated (and therefore particularly pure) gas flow that flows out of the outlet 6 and is discharged from the filter unit 1 into the environment U is Figure 1 The outlet 6 is preferably designed so that the gas flowing out of the top 44 and processed by the catalyst 4 can directly or indirectly enter the outlet 6. Indirect entry can be achieved, for example, by the gas flowing out of the top 44 entering the outlet 6 through the gap formed between the top 44 and the outlet 6. Preferably, the flow direction of the gas flowing out of the top 44 is at least partially aligned with the flow direction of the gas flowing out of the outlet 6 (see FIG. Figure 1 In this way, the catalytic converter 4 and the outlet 6 are particularly space-saving in arrangement.

[0046] The filter unit 1 may be provided with an outlet conduit 61, which is provided with an outlet 6. The outlet conduit 61 may be used as an interface for connection with another conduit, or may extend into the environment U. The outlet conduit 61 may be provided with a fixing area, to which another conduit may be fixed. The design of the outlet conduit 61 may be such that it sets a specific flow direction of the gas flowing out of the outlet 6 and thus out of the filter unit 1. Preferably, the outlet conduit 61 is an outlet pipe.

[0047] The filter unit 1 also has a support structure (i.e., a load-bearing structure) 8, on which at least the filter device 2 is arranged. Therefore, the filter device 2 can at least be supported by the support structure 8, so that the filter device 2 has a specific position relative to the support structure 8 and therefore relative to the catalyst 4. In particular, the filter device 2 is firmly supported by the support structure 8, thereby ensuring that the filter device 2 can operate stably in the filter unit 1. The filter device 2 is preferably fixed to the support structure 8, for example, by material connection. The fixing method by material connection can be achieved by welding, preferably by welding at multiple points and / or lines. This welding can be nano welding. In other embodiments, the filter device 2 can also be fixed to the support structure 8 by force connection and / or shape connection.

[0048] The support structure 8 delimits a space 81, in which the catalytic converter 4 is at least partially arranged. In this way, the catalytic converter 4 is integrated into the filter unit 1 and is therefore arranged in a particularly space-saving manner. The support structure 8 can have a side wall 82, to which the filter device 2 is fixed and which delimits the space 81 from the side. The support structure 8 can also have a bottom 83, from which the side wall 82 extends. The bottom 83 preferably delimits the space 81 from below, that is, the space 81 preferably extends between the bottom 83 and the outlet 6. The side wall 82 preferably delimits an opening 84, through which the space 81 can be accessed. For example, the catalytic converter 4 can be arranged at least partially in the space 81 through the opening 84. In the installed state of the catalytic converter 4, the catalytic converter 4 can extend through the opening 84, so that it protrudes from the side wall 82 when viewed in the direction of the side wall 82. A part of the catalytic converter 4, that is, the part that protrudes from the opening 84, can therefore be arranged outside the space 81, while the rest of the catalytic converter 4 is completely arranged in the space 81. Alternatively, it is also possible that the catalyst 4 is entirely (ie completely) disposed in the space 81 .

[0049] The support structure 8 preferably surrounds the catalyst 4 in a closed manner. For this purpose, the support structure 8 can be designed at least partially in a tubular shape, and / or the side wall 82 (as seen in a cross-sectional view) surrounds the catalyst 4 in a closed manner. Figure 1 As shown, the support structure 8 can be designed in the shape of an elongated strip, thereby forming a corresponding elongated space 81, in which the catalyst 4 can extend in an elongated shape accordingly. The structure 8 can have a circular (circular, elliptical, etc.) or polygonal (square, rectangular, square, etc.) cross section. The width or diameter of the support structure 8 can be in the range of 50 to 200 mm, preferably 70 to 150 mm, and particularly preferably 90 to 130 mm. In a particularly preferred embodiment, the width or diameter of the support structure 8 is 120 mm ± 10 mm.

[0050] The arrangement of the catalyst 4 in the space 81 can be such that the catalyst 4 (particularly the volume defined by the catalyst housing 41) fills most of the space 81, preferably at least 75%, particularly preferably at least 90%. If the catalyst 4 is at least partially arranged in the space 81, a gap 81.1, 81.2 can be formed between the catalyst 4 and the support structure 8. The gap can include a first gap 81.1 and a second gap 81.2. The first gap 81.1 can be designed in an annular shape, for example in the form of an annular ring, which has a polygonal or circular (preferably a perfect circle) shape. The first gap 81.1 is preferably defined at least by the side wall 43 of the catalyst 4 (and preferably by the side part of the bottom 42) and the side wall 82 of the support structure 8 on the side. The second gap 81.2 can have a non-annular shape. The second gap 81.2 preferably extends between the bottom 42 of the catalyst 4 and the bottom 83 of the structure 8. In other words, the gap 81.2 can be defined by the bottom 42 above and the bottom 83 below. The gaps 81.1 and 81.2 are preferably in fluid communication.

[0051] like Figure 1 As shown, the catalyst side wall 43 can be adjacent to and extend parallel to the side wall 82 of the support structure 8, thereby preferably forming a first gap 81.1. However, another method can also be selected, that is, although the catalyst side wall 43 is adjacent to the side wall 82, it is not parallel, for example, it is inclined, so as to form the first gap 81.1. Figure 1 As can be seen in the figure, the catalyst bottom 42 can be adjacent to and extend parallel to the bottom 83 of the support structure 8 to preferably form a second gap 81.2. However, the second gap 81.2 can also be formed in the following manner: the catalyst bottom 42 is adjacent to the bottom 83, but not parallel, for example, in an inclined shape.

[0052] The outlet pipe 61 with the outlet 6 can be provided with a flange 62, by which the outlet pipe 61 and the outlet 6 are fixed to the support structure 8. This fixing is preferably achieved by a form-fitting and / or force-fitting connection, for example by a threaded connection or a quick connector. The fixing operation is preferably completed by means of a fixing device 63, which is preferably used to establish a form-fitting and / or force-fitting connection between the flange 62 and the support structure 8 (for example, the side wall 82, in particular the free end of the side wall 82 that defines the opening 84). The fixing device 63 is preferably designed so that the flange 62 can be fixed to the support structure 8 using a tool (such as a screwdriver or the like) or without a tool (for example, the fixing device 63 is provided with a lever that can selectively release or establish the connection with the support structure 8). The fixing device 63 preferably has: a first area, where the flange 62 is arranged (preferably removable, for example, by force-fitting and / or form-fitting, in particular by a threaded connection); a second area, where the support structure 8 is arranged by its side wall 82 (preferably non-removable, for example, by material connection, in particular by welding). The fixing device 63 can also be provided with an area where the catalyst 4 (preferably its side wall 43) is arranged and preferably fixed, in particular by force fit, form fit and / or material connection. This area can be an inward area (for example, in the direction of the longitudinal axis of the catalyst 4).

[0053] The flange 62 is preferably designed such that it delimits a space 81, preferably at the upper end of the support structure 8, and / or partially covers an opening 84, so that the gas flowing out of the opening 84 to the environment U can only be discharged through the outlet 6. The flange 62 is preferably provided on its side (inner side) 64 facing the space 81 with an area in which the catalytic converter 4 (preferably via its side wall 43) can be arranged and, for example, also fixed there by force fit, form fit and / or material connection. In particular, the catalytic converter 4 can be inserted into this side 64. Alternatively or additionally, the catalytic converter 4 (for example via its side wall 43) can be arranged on the fixing device 63 and preferably fixed by force fit, form fit and / or material connection. By loosening and subsequently removing the flange 62 from the support structure 8, it is particularly possible to simultaneously remove the catalytic converter 4 from the space 81. However, it is also possible to choose another way, that is, by removing the flange 62, the catalytic converter 4 remains fixed relative to the support structure 8 (for example, by the fixing device 63), for example, in order to perform maintenance (repair, removal, etc.) on the catalytic converter 4.

[0054] like Figure 1 and Figure 2As shown, the filter device 2 is preferably arranged outside the space 81 defined by the support structure 8. In this way, the maintenance (cleaning, replacement, etc.) operation of the filter device 2 can be very simple, and the filter device 2 can be operated without disassembling the filter unit 1, in particular, without moving the position of the outlet 6 and / or the catalyst 4 relative to the support structure 8. In addition, during the manufacturing process, the filter device 2 can also be easily arranged, for example, the support structure 8 is wound around the filter device 2.

[0055] The filtered gas flowing out of the filter device 2 can flow to the catalyst 4 arranged downstream in various ways. Figure 1 and Figure 2 One of the ways is shown. It can be seen that the support structure 8 is provided with a plurality of through holes 85, through which the gas filtered by the filter device 2 can enter the space 81 defined by the support structure 8. The through hole 85 is preferably designed to lead to the first gap 81.1 and / or the second gap 81.2. The side wall 82 may be provided with through holes 85, for example, these through holes are evenly distributed on the surface (preferably the entire surface) of the side wall 82. The bottom 83 is preferably not provided with through holes 85, so it is impermeable to gas, or is designed as a cover. In other embodiments, the bottom 83 may also be provided with some through holes 85. At this time, the filter device 2 is preferably also arranged on the bottom 83, and is preferably fixed to the bottom.

[0056] The through hole 85 can be arranged in various ways. Figure 1 and Figure 2 As shown, the support structure 8 can be provided with a mesh, a fabric and / or a grille, for example, to form at least part of the through-holes 85. It is conceivable that the side wall 82 constitutes a mesh, a fabric and / or a grille. Figure 2 As shown, the structures forming the grid, fabric and / or lattice (in particular the intersecting linear structures) can be provided with some areas, in which the filter device 2 is fixed. For example, it is conceivable that these structures provide linear or point-shaped contact areas between the support structure 8 and the filter device 2, and the filter device 2 is fixed to the support structure 8 by means of these areas by means of material connection.

[0057] The through holes 85 preferably each have a certain size. For example, the maximum distance between two points on the (polygonal, circular, etc.) contour defining the through hole 85 ranges from 0.5 to 1.5 mm, preferably from 0.75 to 1.25 mm. If the through holes 85 are all designed as circles, their respective diameters preferably range from 0.5 to 1.5 mm, more preferably from 0.75 to 1.25 mm.

[0058] The support structure 8 is not limited to a specific material. It can be made of a single material or a plurality of different materials. The support structure 8 is preferably made of metal. For example, the bottom 83 can be fixed to the side wall 82 by material connection (such as welding), thereby manufacturing the support structure 8.

[0059] The filter unit 1 may also be provided with another filter device (not shown in the figure), such as a molecular sieve. The filter device is preferably arranged downstream of the filter device 2 and upstream of the catalyst 4, such as in the space 81, or arranged in the catalyst 4, such as in the space for filling the catalyst filler 40. In addition, the filter device may also be arranged downstream of the catalyst 4. In this way, the gas flowing out of the outlet 6 is filtered by the filter device 2 and processed by the catalyst 4 on the one hand, and further filtered by another filter device on the other hand. In the filtering stage provided by the other filter device, for example, a specific gas (such as carbon dioxide) can be filtered.

[0060] use Figure 1 and Figure 2 The embodiment of the filter unit 1 shown can filter and treat gas (such as exhaust gas) in the following manner. The gas first enters the filter device 2 (see arrow 3 in the figure), where it is filtered, so that specific particles (such as fine particles) are separated and retained from the gas ("screening effect"). Subsequently, the gas in the filtered and preliminary purified state (at this time, the gas may still contain gaseous products such as nitrogen) enters the first gap 81.1 and / or the second gap 81.2 through the through hole 85. The gas entering the first gap 81.1 then flows along the side walls 43, 82 to the catalyst inlet or the catalyst bottom 42, where it enters the catalyst 4 for treatment. The filtered gas that directly enters the second gap 81.2 through the through hole 85 can directly enter the catalyst 4 through the path in the second gap 81.2. After entering the catalyst 4, the gas preferably flows along the entire length of the catalyst 4 so that it is treated through the largest possible contact area, thereby converting the specific medium (such as NOx and other pollutants) in the gas filtered by the filter device 2 as completely as possible. Subsequently, the treated gas flows out of the catalyst 4, for example, through the top 44, and is discharged into the environment U through the outlet 6. At this time, the gas is both filtered and treated, so that it is harmless to the environment U, or the harm is significantly reduced.

[0061] The cleaning of the filter device 2 can be achieved by increasing the pressure in the space 81. The resulting overpressure will balance the pressure between the space 81 and the outside of the side of the filter device 2 through the filter device 2, so that the particles accumulated in the filter device 2 can be removed from the filter device 2. The increase in pressure in the space 81 is preferably achieved through the outlet 6 or the inlet (not shown in the figure; for example, the flange 62 is provided with the inlet), such as by conveying a fluid (such as ambient air, etc.) to the space 81. In one embodiment, the filter unit 1 is provided with a fluid conveying device for conveying a fluid to the space 81, thereby increasing the pressure in the space.

[0062] The invention is not restricted to the features described above; in particular, the features described above can be combined with one another in any desired manner.

Claims

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

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

3. The filter unit (1) according to claim 1 or 2, wherein: The filtering device (2) is fixed on the supporting structure (8).

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

5. The filter unit (1) according to any one of the preceding claims, wherein: The filter device (2) is designed in a planar shape and / or has one or more layers (21, 22), wherein the first layer (21) preferably has a higher filtering accuracy than the second layer (22), wherein the first layer (21) is preferably arranged downstream of the second layer (22).

6. The filter unit (1) according to any one of the preceding claims, wherein The filtering device (2) is cylindrical and / or tubular.

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

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

9. The filter unit (1) according to any one of the preceding claims, wherein: The filtering device (2) contains stainless steel.

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

11. The filter unit (1) according to any one of the preceding claims, wherein: The support structure (8) tightly surrounds the catalytic converter (4).

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

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

14. The filter unit (1) according to any one of the preceding claims, wherein The support structure (8) has a plurality of through holes (85), and preferably, the gas in a state of being filtered by the filter device (2) can enter the space (81) defined by the support structure (8) through the through holes.

15. The filter unit (1) according to claim 14, wherein: The support structure (8) has a side wall (82), and the filter device (2) is fixed to the side wall (82), wherein the side wall (82) has at least a part of the through hole (85), wherein the support structure (8) preferably has a bottom (83), and the side wall (82) extends from the bottom, wherein preferably the bottom (83) has a part of the through hole (85) or is impermeable to the gas to be treated by the filter unit (1) and / or the bottom (83) is designed as a cover.

16. The filter unit (1) according to claim 14 or 15, wherein: The support structure (8) has a mesh, a fabric and / or a grid to form at least a portion of the through holes (85).

17. The filter unit (1) according to any one of claims 14 to 16, wherein: Each through hole (85) is defined by a contour such as a polygon or a circle, wherein the maximum distance between two points on the contour is in the range of 0.5 mm to 1.5 mm, preferably in the range of 0.75 mm to 1.25 mm, or the diameter of each through hole (85) is in the range of 0.5 mm to 1.5 mm, preferably in the range of 0.75 mm to 1.25 mm.

18. The filter unit (1) according to any one of the preceding claims, wherein The supporting structure (8) is made of metal.

19. The filter unit (1) according to any one of the preceding claims, further comprising an outlet duct (61) having the outlet (6), wherein: The outlet conduit (61) is preferably an outlet pipe.

20. The filter unit (1) according to claim 19, wherein The outlet duct (61) has a flange (62) by means of which the outlet duct (61) is fixed to the support structure (8), wherein the flange (62) preferably delimits the space (81) delimited by the support structure (8), and / or wherein the side wall (82) of the support structure (8) preferably defines an opening (84), which is at least partially covered by the flange (62).

21. The filter unit (1) according to claim 19 or 20, wherein: The outlet pipe (61), preferably the flange (62), is fastened to the support structure (8) by means of a positive and / or non-positive connection, wherein the positive and / or non-positive connection preferably comprises a threaded connection.

22. The filter unit (1) according to any one of the preceding claims, wherein The catalyst (4) has a preferably cylindrical or sleeve-shaped housing (41), and the catalyst (4) preferably has a catalyst filling (40) arranged in the housing (41), wherein the catalyst filling (40) preferably has a granular shape and / or is at least partially arranged in a spherical shape.

23. The filter unit (1) according to claim 22, wherein: The housing (41) comprises a catalyst bottom (42) and a catalyst side wall (43) extending from the catalyst bottom (42), wherein the gas is preferably conveyed to the catalyst (4) for treatment via the catalyst bottom (42).

24. The filter unit (1) according to claim 23, wherein The catalyst side wall (43) is adjacent to and / or extends parallel to a wall of the support structure (8), such as the side wall (82) of the support structure (8), and / or wherein the catalyst bottom (42) is adjacent to and / or extends parallel to another wall of the support structure (8), such as the bottom (83) of the support structure.

25. The filter unit (1) according to any one of the preceding claims, further comprising a further filter device, such as a molecular sieve, wherein: The further filter device is preferably arranged downstream of the filter device (2) and upstream of the catalytic converter (4), or in the catalytic converter (4) and / or in the space (81) defined by the support structure (8).

26. A method of filtering and treating gases such as exhaust gases, the method comprising the steps of: - providing a filter unit (1) according to any one of the preceding claims; - filtering the gas through the filter device (2) of the filter unit (1); - treating the filtered gas through a catalyst (4) of the filter unit (1); as well as - The filtered and treated gas is discharged from the filter unit (1) through the outlet (6) of the filter unit (1).

Images