FILTER MODULE, PLANT FOR DUST FILTRATION AND METHOD FOR SEPARATION OF DUST FROM A GAS FLOW

Description

[0001] The invention relates to a filter module, a system for filtering dust containing the filter module, and a method for separating dust from a gas stream using the system. The filter module and system are designed to be particularly explosion-proof, thus enabling explosion-proof dust separation.

[0002] Filter modules and filter systems for different media are generally known from the prior art. For example, WO 2019 / 063335 A1 describes a generic filter device comprising a filter medium body clamped between two housing parts. This filter medium body is clamped between the two housing parts without the need for a seal, meaning that according to this publication, edge sealing is no longer necessary. The spaces between the pleats of the filter medium body are fluid-permeable on the long side transverse to the pleats without a filtering function. This generic filter device is particularly suitable for liquid filtration, for example, oil filtration.However, due to its mechanical design, it cannot be used for filtering dust, specifically explosive dust, since neither the fastening of the filter medium body nor the downstream side of the filter device are designed for higher pressures, especially explosion pressures.

[0003] CN 111 841 199 A belongs generally to the technical field of air purification and relates in particular to a fastening device, a sieve and an air purification device. The fastening device comprises a first frame body and a second frame body which are used to clamp filter paper, wherein the first frame body is provided with a first comb frame; the second frame body is provided with a second comb frame; the first comb frame and the second comb frame are each provided with comb teeth which extend into bending gaps in the filter paper. The comb teeth guarantee the rigidity of the filter sieve and the distance between each two adjacent bends in the filter paper.The fixing device replaces the conventional gluing and sealing of the filter paper, improves the stability and high-temperature resistance of the filter screen, reduces the stability and high-temperature resistance of the filter screen, reduces the processing operations and material requirements of the filter screen, improves the assembly efficiency of the filter screen and saves consumables during the processing of the filter screen.

[0004] From US 2015 / 0013287 A1, a filter frame for holding a filter is known, which is provided with a plurality of folds to form alternating ridges and troughs, comprising: a first frame portion having a first holding portion having a side corresponding to a first side of the filter, for holding the filter; a positioning portion provided on the first holding portion for determining a position of the filter; and a second frame portion having a second holding portion for holding the filter by clamping the filter between the first and second holding portions. The second holding portion is provided so as to be able to oppose the first holding portion across the filter and has a side corresponding to a second side of the filter.

[0005] WO 2003 / 059490 A1 describes a filter with replaceable filter paper for a dust collector. The filter comprises box-shaped upper and lower filters, each having a filter combining means and a filter paper positioning means, as well as a filter paper fastening means for fastening filter paper to the filter paper positioning means of the upper filter and the lower filter combined by the filter combining means.

[0006] US 2017 / 0095762 A1 discloses a system with a sensor connected to a filter of a specific type. The sensor measures the pressure drop across the filter and communicates with the control unit. An air handler forces air through the filter and communicates with a control unit. The control unit includes an interface connection, a memory, and a microprocessor. The interface connection receives the air flow rate of the air handler and the pressure drop across the filter. The memory stores the relationship between pressure drop and air flow rate for a filter of the same filter type when the filter is clean and when the filter is exhausted. The memory also stores the relationship between pressure drop and filter life of a filter of the filter type. The processor determines the remaining filter life based on the received and stored information. The display receives information from the controller and displays it.

[0007] KR 10 2015 0139664 A describes an air purifier according to an embodiment comprising a memory that stores a flow rate-pressure difference correlation diagram for operating conditions of a plurality of filters; a differential pressure sensor that measures the pressure difference of an internal filter; a flow sensor that measures the flow rate of the air flowing into the internal filter; and a filter replacement period management part that selects a diagram from the flow rate-pressure difference correlation diagrams of a plurality of filters stored in the memory based on the initial pressure difference and flow rate measured in an initial installation step, and determines the replacement period of the internal filter according to whether the pressure difference and flow rate measured periodically thereafter agree with the selected diagram or not.

[0008] DE 10 2016 008 204 B4 The invention relates to an explosion protection device for the explosion-related decoupling of two plant components which are connected to one another by means of a pipeline in which explosive dusts or gases are conveyed in a flow direction, wherein a tubular body is arranged within the pipeline, wherein the tubular body contains an inlet opening and an axially spaced outlet opening with at least one closing element arranged therebetween.The explosion protection device is characterized in that at least two axially spaced, differently designed closing elements are provided between the inlet and outlet openings and are arranged alternately one after the other in the tubular body, each closing element containing two bending plates projecting obliquely into the tubular body, which increasingly narrow the flow cross-section in the direction of flow, a radial closing element containing two bending plates on opposite inner walls of the tubular body and a central closing element containing two bending plates arranged in the center of the tubular body and connected to one another in a V-shape, the bending plates being elastically or plastically bendable such that, in the event of an explosion pressure, they close the flow cross-section of the tubular body in the opposite direction to the flow direction (10).

[0009] CN 113 599 929 A discloses a fire and explosion-proof dust extraction device and relates to the technical field of dust extraction, wherein the device comprises a machine body and a dust extraction hopper arranged below the machine body, a filter cartridge is arranged in the machine body, the filter cartridge comprises a mounting plate, a cartridge core and a filter cloth, a first fixing plate is fixedly arranged in the machine body, and a mounting frame is fixedly arranged on the bottom wall of the first fixing plate; a first fixing plate is fixedly arranged in the machine body and a mounting frame is fixedly arranged on the bottom wall of the first fixing plate; mounting grooves into which the fixing plates can be inserted are formed in the two sides of the mounting frame and attachment plates are fixedly arranged on the bottoms of the mounting grooves;A limiting plate is hinged to each attachment plate, a protruding portion, used for abutting the fixing plate, is arranged on the top of the limiting plate, and a limiting assembly, used to limit the position of the limiting plate to allow the protruding portion and the fixing plate to be kept in an abutting state, is arranged on the attachment plate. When the filter cloth or the entire filter cartridge needs to be replaced, the limiting assembly removes the position limitation of the limiting plates, so that the protruding portion on the limiting plates is separated from the engagement with the mounting plates. Then, the mounting plates are moved out of the mounting grooves, the entire filter cartridge can be removed. The operation is simple, and the filter cartridge is convenient to remove and replace.

[0010] Although a wide range of different systems for filtering various types of dust is available today, many plant operators report that there is no safe and technically and economically viable solution for the dry separation of highly explosive (above dust class St 2), hot dusts, such as those generated during the blasting of metal parts. In addition to metallic and organic dusts, this includes, in particular, light metal dusts, which can generate temperatures of up to 3,000 °C during an explosion and exhibit a significantly more violent explosive effect than normal metallic or organic dusts.

[0011] Today, explosion protection concepts for systems for filtering explosive dusts generally involve installing an explosion venting device and an explosion isolation device on a filter system. These devices must be individually designed for each filter system and each type of dust, and they must also be coordinated with each other. This poses a significant risk of miscalculations. The generally applicable design principles are inadequate, particularly with regard to metal dusts, and sometimes produce incorrect results, which can even increase the risk in some cases.

[0012] Depending on their material properties, dusts are classified into three dust classes (St 1 to St 3) based on their explosive potential. For metal dusts of dust class St 1 (K St value up to 200 bar*m / s), there are approved pressure relief devices that can be used as part of a protection concept. These devices no longer exist for metal dusts of class St 2 (K St value up to 300 bar*m / s). Protection devices for St 3 metal dusts (K St value over 300 bar*m / s) are considered unrealistic based on the current state of the art because the raw gas volumes of the filter housings are too large. However, dusts of classes St 2 and St 3 are becoming increasingly common in industrial processes.

[0013] The K St value is a dust- and test-method-specific parameter calculated from the volume dependence of the maximum pressure rise over time (cubic law). Numerically, it is equal to the value for the maximum pressure rise over time in a 1-meter container. The test conditions are specified in the guidelines VDI 3673 Part 1 and VDI 2263 Part 1, as well as in ISO 6184-1.

[0014] The current design of industrial dust extraction or filter systems (extraction capacities from 2,000 m 3 / h to 9,000 m 3 / h), which are increasingly positioned in closed halls directly near the production processes, presents problems in several respects: The relatively high raw gas volume has a significant impact on the explosion-proof design of the filters. As the raw gas volume increases, so does the size of the dust cloud that can form in the system, and thus the severity of a potential explosion. The sound pressure level of over 75 dB(A) during operation can only be reduced to a safe, permissible level with considerable additional effort (e.g., soundproof booths). Due to their size, the filter systems require a relatively large amount of space. The filter cartridges are often cleaned using compressed air pulses. These pressure surges also generate a high sound pressure level of over 70 dB(A). The required powerful drive fans consume a lot of energy. In the absence of suitable dry filters for highly explosive dusts, wet dust extractors are often used for such materials, which are problematic from an environmental perspective.

[0015] There is therefore a need for a system that overcomes the disadvantages outlined above. In particular, inquiries and subsequent discussions with automotive, battery, and blasting equipment manufacturers have identified a need for systems for filtering highly explosive, flammable dusts, for which currently available dust collectors do not provide a truly satisfactory solution.

[0016] The invention is therefore based on the object of providing a novel filter module and a novel system for filtering dusts as well as a method for separating dusts from a gas stream, in which the loss of effective filter area during operation is avoided, while at the same time the raw gas volume is significantly reduced to minimize the risk of explosion.

[0017] This object is achieved according to the invention in a first aspect of the present invention by a filter module (1) for dusts, comprising a first arrangement of at least two comb-like base elements (101a, 101b) which are accommodated in a base frame (103), a second arrangement of at least two comb-like fixing elements (105a, 105b) which are accommodated in a fixing frame (107), wherein the comb-like fixing elements (105a, 105b) are geometrically complementary to the comb-like basic elements (101a, 101b), a fastening device (109) for reversibly connecting the base frame (103) to the fixing frame (107) and a filter material (111) which has a fold, wherein the filter material (111) is placed over the first arrangement of comb-like basic elements (101a, 101b) and is fixed to the second arrangement of comb-like fixing elements (105a, 105b), wherein the fixing frame (107) has a lattice structure with webs (1071) and slots (1073), wherein the webs (1071) each support the ends of the fold of the filter material (111) on a clean gas side, so that the filter module (1) is designed to be explosion-proof.

[0018] The dusts to be filtered with the filter module (1) according to the invention are in particular explosive dusts, especially metal dusts and organic dusts, in particular light metal dusts.

[0019] The term "comb-like base elements," like the term "comb-like fixing elements," refers, in the context of the present invention, to a component that has a comb-like toothing or prongs that are uniformly formed along their length and all open in the same direction. These can be adjusted in height, spacing (pitch), and inclination, allowing the use of any filter material depending on the respective filtering task.

[0020] In the "arrangement" according to the invention, two or more comb-like base elements (101a, 101b) or comb-like fixing elements (105a, 105b) are arranged adjacent to one another at a distance from one another, with the teeth within the arrangement being aligned with one another. The arrangement is accommodated in the base frame (103) or in the fixing frame (107), respectively, so that the components cannot shift relative to one another.

[0021] The filter material (111) having a fold is inserted and fixed between the comb-like base elements (101a, 101b) and the comb-like fixing elements (105a, 105b).

[0022] According to the invention, it is essential that the comb-like fixing elements (105a, 105b) are geometrically complementary to the comb-like basic elements (101a, 101b), ie the comb-like fixing elements (105a, 105b) can be inserted into the comb-like basic elements (101a, 101b) since the respective toothings are identical.

[0023] According to the invention, the fastening device (109) serves to fasten the fixing frame (107) to the base frame (103), for example by screwing, so that the filter module results as a compact structural unit.

[0024] The filter module (1) according to the invention has the advantage that, thanks to the arrangement, each fold of the filter material (111) is mechanically firmly clamped, which prevents material fatigue. Due to the clamping, adhesive beads, for example, as known from the prior art, are no longer required to stabilize the filter material (111) or an entire filter element. Therefore, in principle, all filter materials, including coated ones, can be used.

[0025] However, a further significant advantage of the inventive filter module (1) with firmly clamped filter material (111) compared to existing systems is that its folds can no longer compress when a gas stream to be purified flows through them, thus avoiding the loss of a large portion of the filter surface. The free flow through the filter material (111) and thus the inventive filter module (1) remains almost unrestricted.

[0026] In addition, any wringing of the filter material (111), which could lead to filter breakage, is completely eliminated.

[0027] This also means significantly lower energy requirements for the drive (e.g., fan) that generates the gas flow. Tests and calculations have shown that the same extraction power, for which current systems require 15 kW, can be achieved with the filter module (1) according to the invention using only 7 kW. This protects the environment and significantly reduces operating costs.

[0028] By reducing the pressure losses in the filter modules (1) according to the invention, the power requirement of the fans is almost halved, the operating costs are reduced, and thus the environmental aspect (reducing CO2 emissions) is taken into account.

[0029] The filter module (1) according to the invention can therefore be designed for all conceivable areas of application and can be used universally.

[0030] The "clean gas side" here refers to the side of the filter module (1) according to the invention from which the purified gas is extracted. The "clean gas side" is also the side facing away from a potential dust explosion.

[0031] The fixing frame (107) is preferably formed integrally with the comb-like fixing elements (105a, 105b), ie it carries these comb-like fixing elements (105a, 105b) on its side facing the interior of the filter module (1) according to the invention.

[0032] In the event of a dust explosion on the raw gas side (the side facing the supply channel (5) as opposed to the clean gas side), the pressure essentially spreads through the filter module (1) according to the invention. This results in a certain deformation of the fixing frame (107) toward the clean gas side. This deformation (a type of "bulging") also deforms the comb-like fixing elements (105a, 105b) in such a way that the tips move toward each other, thereby further increasing the clamping of the filter material (111) on the comb-like base elements (101a, 101b).

[0033] Furthermore, in the event of a dust explosion on the raw gas side, the webs (1071) support the pleat tips of the filter material (111), i.e., precisely the area most exposed to the explosion pressure. This prevents the filter material (111) from tearing at these pleat tips and preventing the filtered dust from spreading to the clean gas side.

[0034] The construction according to the invention enables, in cases where the highest possible stability and the strongest possible clamping are necessary, this can be achieved by purely mechanical means.

[0035] In one embodiment of the invention, the distance between the at least two comb-like base elements (101a, 101b) is at least 30 mm to 50 mm, preferably 40 mm, and the distance between the at least two comb-like fixing elements (105a, 105b) is at least 30 mm to 50 mm, preferably 40 mm. This is intended to ensure that the clamped filter material (111) does not settle between the comb-like elements (101a, 101b, 105a, 105b) or form pockets.

[0036] To ensure adequate fixation of the filter material (111), the filter material (111) is fixed for each pleat over a length of at least 40 mm, preferably at least 50 mm (the specific length depends on the height of the pleats), between one of the comb-like base elements (101a, 101b) and one of the corresponding comb-like fixing elements (105a, 105b). The length of the fixation depends to a certain extent on the size of the comb-like elements (101a, 101b, 105a, 105b); therefore, longer lengths are also possible.

[0037] In a further development, the filter material (111) is supported at the tip of each pleat on at least one side by one of the comb-like base elements (101a, 101b) or by one of the comb-like fixing elements (105a, 105b). This prevents a type of bag formation in which material to be filtered accumulates on the upstream side and causes the filter material (111) to bulge.

[0038] Another embodiment provides that the fixing frame (107) has slots (1073) whose length corresponds to the distance between the at least two comb-like base elements (101a, 101b) (or between the at least two comb-like fixing elements (105a, 105b)) and whose spacing corresponds to the spacing of the folds of the filter material (111). The aforementioned webs (1071) are provided between the slots (1073). This ensures that the targeted purge air achieves a cleaning efficiency of almost 100% in each fold, which has already been confirmed by test series.

[0039] The width of the slits should preferably correspond to the opening of the fold less approximately 3 mm. This dimension is based on manufacturing reasons (technical feasibility).

[0040] A further development of the filter module (1) according to the invention provides that by fixing the filter material (111) between the first arrangement of comb-like basic elements (101a, 101b) and the second arrangement of comb-like fixing elements (105a, 105b) between two adjacent arrangements, together with the grid structure of the fixing frame (107), individual filter chambers (113) are formed.

[0041] These filter chambers (113) are bounded on two opposite sides by the material of the comb-like base elements (101a, 101b) and the comb-like fixing elements (105a, 105b), respectively, and on the other two sides by the folded filter material (111), which is clamped in place according to the invention. In this way, each of the filter chambers (113) is inherently stable, while the filter material (111) can only be deformed to a minor extent.

[0042] During regular use of the filter module (1) according to the invention, the dust is collected on the filter material (111) on the raw gas side. Due to the stability of the filter chambers (113), no bagging can occur, as is the case with conventional filters. When the filter module (1) according to the invention is cleaned by blowing in an air stream from the clean gas side to remove the collected dust, the filter material (111) remains stable, ensuring maximum flow, which enables optimal cleaning.

[0043] In the event of a dust explosion on the raw gas side, the filter chambers (113) also remain stable and ensure maximum flow, so that the explosion pressure can escape very quickly and over the maximum area.

[0044] The filter material (111) can preferably be provided as a type of filter block with pre-folded pleats and edge seals, so that insertion into and removal from the filter module (1) according to the invention can be accomplished in a few simple steps. The pleats of the filter material (111) are optimally matched to the comb-like base elements (101a, 101b) and the comb-like fixing elements (105a, 105b).

[0045] If further device features or method features are mentioned in the description of the filter module (1) according to the invention, these relate in particular to the system (100) according to the invention and to the method according to the invention. Likewise, material features mentioned in the description of the method according to the invention relate to the filter module (1) according to the invention and the system (100) according to the invention.

[0046] The above-mentioned object of the invention is achieved in a second aspect by a system (100) for filtering dust, comprising the filter module (1) according to the invention, as described above, a housing (3) which has a receptacle for the filter module (1), a supply channel (5) arranged upstream of the receptacle for the filter module (1), a suction device (7) arranged in the housing (3) which is in flow connection with the filter module (1), a discharge channel (9) arranged downstream of the suction device (7), a pressure sensor which is arranged between the filter module (1) and the suction device (7), and a switch box (13) which is electrically connected at least to the suction device (7) and the pressure sensor.

[0047] The system (100) according to the invention is in particular an explosion-proof system for filtering explosive dusts, especially metal dusts and organic dusts, in particular light metal dusts.

[0048] The supply channel (5) upstream of the filter module (1) according to the invention is designed to convey the gas stream to be purified. Intake is generally achieved via a correspondingly designed intake device (7) located downstream of the filter module (1) according to the invention in or on the discharge channel (9).

[0049] The holder for the filter module (1) is preferably arranged vertically.

[0050] The pressure sensor provided according to the invention detects the pressure difference between the upstream side and the downstream side of the filter module (1) according to the invention, whereby the degree of clogging of the filter material (111) can be determined.

[0051] In the case of an explosion, the explosion speed (i.e. the reaction speed) is fundamentally important. The faster an explosion and the larger the raw gas volume of a filter system, the greater the gas volume that forms in the system per unit of time and the higher the pressure will rise if the explosion pressure venting does not occur quickly enough. According to the state of the art, filter systems with a correspondingly larger raw gas volume are used to achieve higher air throughput capacities. Filter systems with a larger raw gas volume require larger explosion pressure venting areas, which are created by installing appropriately dimensioned autonomous protection systems (e.g. flameless explosion venting according to EN 16009). This leads to high additional costs, if technically possible at all. In contrast, in the present invention the raw gas volume of the filter system (100) always remains approximately the same (approx.0.1 m 3 < ), even if the air flow doubles or triples. This significantly reduces the overall risk of damage in the event of an explosion.

[0052] The present invention therefore takes a different approach by taking into account the fact that the pressure increase within the system is lower the smaller the raw gas volume is on the one hand and the more unhindered the gas-dust mixture can flow through a system, ie leave the interior of the filter system (100), on the other hand.

[0053] In addition to the advantages already mentioned for the filter module (1) according to the invention, the system (100) according to the invention has the further advantages that the raw gas volume of a filter module (1) according to the invention is only approximately 0.1 m 3 (up to 100 l), while the raw gas volume of known filter systems with comparable extraction capacity is approximately 2.5 m 3 . This small volume means extreme risk minimization with regard to all explosion-related issues.

[0054] Due to its design, the system (100) according to the invention with the filter module (1) according to the invention is suitable for hot and highly explosive dusts of class St 3, and all less explosive materials can also be filtered with it - error-prone designs in individual cases are no longer necessary.

[0055] The compact design of the system (100) according to the invention ensures a pressure surge resistance (pred) of at least 2 bar (g). These factors enable safe explosion pressure relief along the flow path into the outlet channel; no additional relief devices are required.

[0056] The filter system (100) according to the invention can be freely positioned within a hall (e.g., a production hall) since no exhaust air piping is required. This is achieved by using a HEPA filter. Therefore, no fresh air needs to be introduced into the hall, thus eliminating the need for additional energy for the hall heating. The slide valve provides fire protection, as it seals the dust carriage airtight and pressure-tight. Due to the integrated sound insulation, the system (100) according to the invention can be positioned directly at the extraction points without additional effort, thus avoiding long piping runs and thus further flow losses.

[0057] Even in the event of a dust explosion in a system (100) according to the invention, no safety distances for persons or other devices need to be maintained. Even in the event of a dust explosion, the surface temperature of the housing (3) of the system (100) according to the invention does not reach a critical value that would endanger the surrounding area. In contrast, explosion pressure vents according to the state of the art can quickly reach a surface temperature of 400°C, so protective distances must be provided.

[0058] In a further development, the system (100) according to the invention has a volumetric flow rate of 3,000 m 3 / h to 4,000 m 3 / h for a raw gas volume of up to 0.1 m 3 , wherein the system (100) is designed for a K St value of up to 500 bar*m / s. ​​A K St value of up to 500 bar*m / s occurs particularly with light metal dusts and metallic dusts, with light metal dusts in particular reacting extremely quickly and generating temperatures of up to 3,000°C.

[0059] As stated in the introduction, according to current knowledge, no dust extraction systems are known that have protective devices for St 3 metal dusts with K St values ​​above 300 bar*m / s. ​​In fact, such systems are considered impractical due to the large raw gas volumes. The present invention, however, provides a system that actually enables K St values ​​of up to 500 bar*m / s due to the structurally reduced raw gas volume.

[0060] In a further development of the system (100) according to the invention, this further comprises a free space (303) arranged within the housing (3) between the filter module (1) and the suction device (7), a blower unit with a blower motor and a blower outlet, which is arranged to be movable in the free space (303), wherein the blower outlet is arranged at the level of the filter module (1) and the blower unit is movable parallel to the filter module (1), a dust collection device (17) arranged below the holder for the filter module (1) in the feed channel (5), and a shut-off valve arranged between the holder and the dust collection device (17).

[0061] Preferably, the slots of the blower outlet correspond in size and arrangement to the slots (1073) in the fixing frame (107) when moving the blower unit.

[0062] This inventive development enables the filter material (111) to be blown clean at regular intervals, particularly when the pressure loss between the upstream side of the inventive filter module (1) and its downstream side becomes too great. Because the filter material (111) is firmly clamped in the manner described above, cleaning the pleats is made significantly easier. The pleats can be blown clean at regular intervals of the dust separated from the gas stream, which gradually settles during the separation process and increasingly impairs the filter performance. For this purpose, a cleaning unit newly designed for this system (100) is used, comprising a blower unit with a blower motor and blower outlet.

[0063] Within the free space (303), the blower unit can be moved linearly on the downstream side of the filter module (1) according to the invention, wherein the dust blown out of the pleats of the filter material (111) is conveyed into the dust collection device (17), from where it can be properly disposed of.

[0064] The gate valve (see figures) prevents material from escaping when the dust cart is emptied while the system (100) is in operation. Fire protection is ensured by the use of the gate valve. Closing the gate valve makes the dust cart airtight, smothering any potential fire.

[0065] Another embodiment of the system (100) according to the invention further comprises a decoupling module (19) for explosively decoupling the system (100) from the supply channel (5), which is arranged between the receptacle for the filter module (1) and the supply channel (5). This ensures that an explosion that may occur despite all precautionary measures will not seriously damage either the system (100) or the supply channel (5). The decoupling module (19) is designed to interrupt the supply channel (5) against the flow direction (i.e., against the explosion path), thus preventing the explosion from spreading.

[0066] Additionally, it has proven advantageous to provide a flame arrester (see figures), consisting of a housing preferably filled with steel wool. This flame arrester is mounted directly between the supply duct (5) and the decoupling module (19).

[0067] For the compactness of the system (100) according to the invention, it has proven advantageous if the discharge channel (9) arranged downstream of the intake device (7) is designed as a pressure relief device. This eliminates the need for the additional provision of an external pressure relief device, as is common in the prior art.

[0068] In a specific development, the discharge channel (9) within the system (100) according to the invention is deflected several times (various changes of direction) and / or provided with free volumes to relieve the pressure. For this purpose, for example, a free volume is provided around the intake device (7), which can absorb and reduce pressure before the residual pressure can spread through an opening into the repeatedly deflected discharge channel (9). The free volume around the intake device (7) also serves to cool it during normal operation.

[0069] An essential embodiment of the system (100) according to the invention provides that the discharge channel (9), the switch box (13), and the decoupling module (19) are integrated into the housing (3), so that the system (100) is designed to be explosion-proof. This embodiment, due to the high degree of integration, results in a compact system (100) that has no add-on parts or elements other than the externally provided supply channel (5).

[0070] As already explained above, the switch box (13) is also integrated into the housing, which is difficult to achieve with conventional systems. However, according to the present invention, the switch box (13) is cooled by the sophisticated guidance of the gas flows. For this purpose, the housing (3) preferably has its own air supply opening in the floor area, through which fresh air is drawn into the switch box (13) for cooling. The switch box (13) also has a pressure-tight fluid connection to the free space (303), which in turn is vented by means of the intake device (7). The intake device (7) therefore indirectly draws the cooling air out of the switch box (13). The fluid connection is designed as a check valve so that explosion pressure cannot spread into the switch box (13).

[0071] Another development provides that the system (100) according to the invention further comprises active and / or passive soundproofing devices in order to reduce the sound pressure level.

[0072] According to the invention, these soundproofing devices can consist, on the one hand, of soundproofing elements that absorb sound through a type of sandwich construction. These soundproofing elements are preferably used to line the base frame of the system (100).

[0073] According to the invention, these soundproofing devices can also consist of the discharge duct (9) in the base frame of the system (100) being deflected several times, which further increases soundproofing. This type of soundproofing device coincides with the pressure relief provided in the event of a dust explosion.

[0074] With this inventive measure of the special flow guidance in the system (100), the sound pressure level can be reduced to below 60 dB (A), compared to 75 dB (A) in filter systems of the prior art.

[0075] It is further preferred to equip the system (100) according to the invention with a HEPA fine dust filter, which can be flanged to the outlet (see figures). Thus, the air exiting the system (100) according to the invention can be released directly into the environment, e.g., into the hall, without having to provide an outlet to the outside. Both the residual pressure of the exhaust air and its purity make this possible.

[0076] The system (100) according to the invention preferably has a room volume of 6 m³ to 7 m³ with an extraction capacity of 7,000 m³ / h to 8,000 m³ / h. This requires only a fraction of the space in the halls required by conventional filter systems. Good accessibility to the individual components, such as filter modules (1), decoupling devices, or dust carts, facilitates and accelerates measures such as cleaning, replacement, inspection, etc., as well as space for the control cabinet and cabling.

[0077] The concept significantly improves system availability, as if one fan (in the intake system (7)) fails, the other fans take over the air flow rate, thus maintaining the air flow rate at a constant level. Even during repairs, the concept allows the system (100) to remain in operation. With the current technology, however, the filter system fails completely.

[0078] The size of a system (100) according to the invention (ie room volume) with an extraction capacity of 7,500 m 3 < / h is about 6.6 m 3 < , while a conventional filter system according to the state of the art with the same capacity occupies about 14 m 3 < to 20 m 3 <.

[0079] Since all essential functions are already integrated into the system (100) according to the invention, its installation and commissioning are extremely simple and can be carried out without the need for external assembly teams. In principle, only the conveyor line for the material supply needs to be connected to the system (100) according to the invention; the connection to the power grid is based on the plug-and-play principle.

[0080] The above-mentioned object is achieved in a third aspect of the present invention by a system combination for filtering dust, comprising at least two systems (100) according to the invention for filtering dust as described above, wherein the at least two systems (100) are arranged one above the other and are aligned with each other so that the supply channels (5) are located one above the other, a funnel unit (21) which receives the feed channels (5) of the at least two systems (10) and decouples them from each other in terms of flow.

[0081] The dust blown out of the filter modules (1) according to the invention can be collected and discharged separately from the supply channels (5) via the funnel unit provided according to the invention.

[0082] Due to its modular concept, the system combination according to the invention makes it possible to subsequently double or triple the volume flow rate. This can be achieved by assembling the individual systems (100) according to the invention in a modular manner. Depending on the required extraction capacity, up to three systems (100) according to the invention can be arranged one above the other. Subsequent expansion, and thus, for example, doubling the extraction capacity, can also be achieved in just a few simple steps.

[0083] A further advantage of the system (100) according to the invention within the system network is that the individual systems (100) according to the invention can be operated independently of one another. For this purpose, separate supply channels (5) can be provided for each individual system (100) according to the invention. Due to the control cabinet (13) present in each individual system (100) according to the invention, independent control is also possible.

[0084] If process features are mentioned in the description of the filter module (1) according to the invention and / or the system (100) according to the invention, these relate in particular to the process according to the invention. Likewise, material features mentioned in the description of the process according to the invention relate to the filter module (1) according to the invention and / or the system (100) according to the invention.

[0085] The above-mentioned object is achieved in a fourth aspect of the present invention by a method for separating dusts from a gas stream, comprising the steps a) introducing the dust-laden gas stream into a feed channel (5) of a system (100) for filtering dust, as defined above; b) sucking the dust-laden gas stream with a suction device (7) of the system (100) into a filter module (1) for dust, as defined above; c) separating the dust from the dust-laden gas stream in the filter module (1), wherein the dust is collected in a filter material (111) and the gas stream is discharged via a discharge channel (9) of the system (100); d) continuously recording the pressure profile of the gas stream downstream of the filter module (1); e) continuously measuring the flow velocity in the system (100) by means of a flow sensor; f) suspending steps a), b) and c) when the pressure falls below a predetermined level; g) cleaning or replacing the filter module (1), h) restart the procedure with step a).

[0086] In step c), the gas stream discharged via a discharge duct (9) of the system (100) according to the invention can also be routed through an additional high-efficiency particulate matter (HEPA) filter and discharged. This allows the system (100) according to the invention to be operated directly in enclosed spaces without endangering people.

[0087] The method described for the operation of a single system (100) according to the invention can be applied almost identically to the system network according to the invention. During this system network operation, one of the systems (100) takes over the power of the other system (100) during the cleaning process, so that the flow velocity in the supply channel (5) does not fall below 20 m / s.

[0088] Further objects, features, advantages, and possible applications will become apparent from the following description of non-limiting embodiments of the invention, taken in conjunction with the figures. All described and / or illustrated features, individually or in any combination, constitute the subject matter of the invention, regardless of their summary in the claims or their references. They show: Fig. 1: a schematic exploded view of a filter module 1 according to the invention according to an embodiment of the invention, Fig. 2: a schematic partially cut-away side view of a filter module 1 according to the invention according to an embodiment of the invention, Fig. 3: a schematic detailed view DA1 from Fig. 2 , Fig. 4: a schematic detailed view of DA2 from Fig. 3, Fig. 5: a schematic representation of an inventive system 100 according to an embodiment of the invention from the front, Fig. 6: a schematic representation of an inventive system 100 according to an embodiment of the invention from the side, Fig. 7: a scaled comparison of a conventional filter system according to the prior art with an inventive system 100 according to an embodiment of the invention, Fig. 8: a schematic cut-out partial view of an inventive filter module 1 according to an embodiment of the invention, Fig. 9: a schematic cut-out and expanded partial view of the in Fig. 8 shown filter module 1 according to the invention and Fig. 10 a schematic detailed view DA3 from Fig. 9 .

[0089] In the figures, all identical components are designated by the same reference symbols; however, for reasons of clarity, not all reference symbols are included in all illustrations.

[0090] Figure 1 shows a schematic exploded view of a filter module 1 according to one embodiment of the invention. The filter material 111, which is preferably designed as a type of filter block with pre-folded pleats, is inserted from above into the base frame 103, in which, in this embodiment, five rows of comb-like base elements 101a, 101b, 101c, 101d, 101e are provided. The individual pleats engage with the comb-like base elements 101a, 101b, 101c, 101d, 101e. The fixing frame 107, which also has five rows of comb-like fixing elements 105a, 105b, 105c, 105d, 105e, is then received from above. These comb-like fixing elements 105a, 105b, 105c, 105d, 105e engage in the fold supported from below by the comb-like base elements 101a, 101b, 101c, 101d, 101e and clamp the filter material 111.

[0091] In Figure 2An assembled filter module 1 is shown, cut out in the left-hand area. The circle encloses the detailed view DA1. At the ends or all around, the base frame 103 is connected, for example, by screwing, to the fixing frame 107 via the fastening devices 109.

[0092] Figure 3 shows schematically the detailed view DA1 from Figure 2 This illustration shows how the comb-like fixing elements 105a, 105b, 105c, 105d, 105e are geometrically complementary to the comb-like base elements 101a, 101b, 101c, 101d, 101e and clamp the filter material 111 between them. The rectangle in this illustration encloses the detailed view DA2.

[0093] The detailed view DA2 is shown in Figure 4shown schematically. This further enlarged illustration shows how each pleat tip is supported by an inner corner of the comb-like base elements 101a, 101b, 101c, 101d, 101e or the comb-like fixing elements 105a, 105b, 105c, 105d, 105e in such a way that bulging caused by separated material is prevented. Likewise, sagging of the filter material 111 is avoided.

[0094] In Figure 8 The filter module 1 according to one embodiment of the invention is shown as a schematic cutaway partial view. Specifically, the arrangements of comb-like base elements 101a, 101b, 101c, 101d are shown from below, into which the arrangements of comb-like fixing elements 105a, 105b, 105c, 105d engage from above. The filter material 111 is not present in this illustration.

[0095] The fixing frame 107 here has webs 1071 and slots 1073 that are uniformly spaced and geometrically coordinated with the arrangement of comb-like fixing elements 105a, 105b, 105c, 105d. The illustration clearly shows that the length of the slots 1073 corresponds to the distance between the comb-like fixing elements 105a, 105b, 105c, 105d, and that the width of the slots 1073 corresponds to the distance between their prongs.

[0096] Figure 9 basically shows the representation of the Figure 8 , with the filter material 111 additionally added here. This illustration clearly shows the clamping of the filter material 111 between the individual prongs of the comb-like base elements 101a, 101b, 101c and the comb-like fixing elements 105a, 105b, 105c.

[0097] Since the front edge of the filter module 1 according to the invention is cut open in this illustration, the view falls into the filter chambers 113, which are indicated by an arrow. As already stated above, the filter chambers 113 are each defined by a fold of the filter material 111 and opposing prongs of the comb-like fixing elements 105a, 105b, 105c. At the bottom (or at the top, not visible here), the filter chambers 113 are closed by a tip of the fold. The overall illustration clearly shows how stable the individual filter chambers 113 are.

[0098] In Figure 10 will be the Figure 9Detailed view DA3, schematically represented by a circle, is shown. The section of the filter module 1 according to the invention shown shows the fixing frame 107 at the top, in which, in a sectional view, webs 1071 and slots 1073 are arranged alternately. Comb-like fixing elements 105 are shown again merely for orientation. Since the explosion pressure in the event of a dust explosion spreads from bottom to top in this illustration, it is clearly visible in this illustration how the tips of the pleats of the filter material 111 are supported by the webs 1071.

[0099] Figure 5shows a schematic representation of a system 100 according to the invention from the front. The view initially falls on the decoupling module 19, which is arranged upstream of the filter module 1 (not visible in this illustration). Above the decoupling module 19, the nozzle of the supply channel 5 can be seen, to which a conventional supply line for the gas streams to be cleaned is connected. Below the decoupling module 19 with the filter module 1 located behind it, the dust collection device 17 is arranged, in which the dust blown out of the filter module 1 is collected. In this embodiment, the dust collection device 17 is designed to be mobile, so that it can be replaced quickly.

[0100] To the left of the decoupling module 19 with the filter module 1 located behind it is the control panel 131 for the integrated control box 13, which is not shown in this figure. This makes the control panel very easily accessible. To the right of the side of the housing 3 is the free space 303, not fully shown in this illustration, located between the filter module 1 and the intake device 7.

[0101] In Figure 6 will be the Figure 5 The system 100 shown is shown from the side. The view falls obliquely into the free space 303 of the housing 3, where, in this specific embodiment, two filter modules 1 according to the invention are arranged one above the other. The blower unit with blower motor and blower outlet is arranged in this free space 303, which is not illustrated here. The free space 303 is closed in the operating state, as shown in Figure 5 is indicated.

[0102] Intake device 7 and exhaust duct 9 are not shown in detail. Behind intake device 7, exhaust duct 9 is deflected several times to its exhaust air outlet (not shown). This multiple deflection and additional active and / or passive soundproofing devices significantly reduce the noise level. At the same time, this multiple deflection also serves to relieve pressure, as described above.

[0103] In the presentation of the Figure 6 The control box 13 is shown at the back and is fully integrated into the system 100. It is controlled via the Figure 5 Controlled by the control panel 131 shown on the front.

[0104] Figure 7Finally, a scaled comparison of a conventional filter system S1 (left) according to the prior art with an inventive system 100 (right) according to an embodiment of the invention is shown. While in the conventional filter system S1, a control cabinet S3 must be arranged separately next to the filter system S1, according to the present invention, the control box 13 is integrated into the housing 3 of the system 100.

[0105] The conventional filter system S1, which is already significantly larger in itself, is characterized by the separately provided, but necessary, explosion pressure relief device S5 on the side, the separately mounted silencer S7 on the top, and the separately provided, and equally necessary, explosion isolation device S9 on the side. All of these separate devices on the conventional filter system S1 increase its space requirements enormously. In contrast, the system 100 according to the invention is designed to be very space-saving due to the integration of all necessary devices.

[0106] The design of the filter module 1 according to the invention and the system 100 according to the invention were developed using flow simulations, and the explosion-related effects were verified through experimental tests. The integration of explosion-related decoupling into the system 100 according to the invention ensures that an explosion cannot spread to other system components. Fire protection is ensured by the double-walled housing design and the low raw gas volume.

[0107] The filter module 1 according to the invention and the system 100 according to the invention make it possible for the first time to extract and filter highly explosive and hot dusts, in particular metal dusts, especially light metal dusts, with a dry separator in which all components required for explosion and fire protection are integrated.

[0108] The explosion-proof decoupling device protected by the German patent DE 10 2016 008 204B4 is used as an integral component of the system.

[0109] The target group for this invention includes, among others, planners, manufacturers, and operators of industrial systems for the automotive, blasting equipment, and blasting media industries, as well as other sectors where highly explosive and / or hot dusts must be filtered. It is assumed that, in the medium term, this invention can replace not only conventional dry separators, but also wet separators, which are extremely problematic from an environmental perspective and are often used to filter explosive dusts.

[0110] In addition to direct marketing to the above-mentioned target groups, the prospect of using the present invention in connection with battery test benches is envisaged.

[0111] It is known from several circles that there is an increased demand for battery testing capacity due to the planned transition to battery-powered vehicles. Since hot metal particles are released during battery testing and must be extracted, the present invention represents an optimal addition to battery test benches. Reference symbol

[0112] 1Filter module 101Comb-like base elements 103Base frame 105Comb-like fixing elements 107Fixing frame 1071Webs 1073Slots 109Fastening device 111Filter material 113Filter chambers 3Housing 303Free space 5Supply duct 7Suction device 9Discharge duct 13Switch box 131Control panel Switch box 17Dust collection device 19Decoupling module 100System DA1Detail 1 DA2Detail 2 DA3Detail 3 SdTState of the art S1Filter system (conventional) S3Switch cabinet S5Explosion pressure relief S7Silencer S9Explosion decoupling

Claims

1. Filter module (1) for dusts, comprising - a first arrangement of at least two comb-like base elements (101a, 101b) that are held in a base frame (103), - a second arrangement of at least two comb-like fixing elements (105a, 105b) that are held in a fixing frame (107), the comb-like fixing elements (105a, 105b) being geometrically complementary to the comb-like base elements (101a, 101b), - a fastening device (109) for reversibly connecting the base frame (103) to the fixing frame (107) and - a filter material (111) which has a folding, wherein the filter material (111) is laid over the first arrangement of comb-like base elements (101a, 101b) and fixed with the second arrangement of comb-like fixing elements (105a, 105b), the fixing frame (107) having a lattice structure with webs (1071) and slots (1073), wherein the webs (1071) on a clean gas side respectively support the ends of the fold of the filter material (111).

2. The filter module (1) according to claim 1, wherein the spacing between the at least two comb-like base elements (101a, 101b) is at least 30 mm to 50 mm, preferably 40 mm, and the spacing between the at least two comb-like fixing elements (105a, 105b) is at least 30 mm to 50 mm, preferably 40 mm.

3. The filter module (1) according to claim 1 or 2, wherein the filter material (111) is fixed for each fold over a length of at least 40 mm, preferably at least 50 mm, between one of the comb-like base elements (101a, 101b) and one of the corresponding comb-like fixing elements (105a, 105b).

4. The filter module (1) according to one of claims 1 to 3, wherein the filter material (111) is supported at the lace of each fold on at least one side by one of the comb-like base elements (101a, 101b) or by one of the comb-like fixing elements (105a, 105b).

5. The filter module (1) according to one of claims 1 to 4, wherein the fixing frame (107) has slots whose length corresponds to the spacing between the at least two comb-like base elements (101a, 101b) and whose spacing corresponds to the spacing of the fold of the filter material (111).

6. The filter module (1) according to one of claims 1 to 5, wherein by fixing the filter material (111) between the first arrangement of comb-like base elements (101a, 101b) and the second arrangement of comb-like fixing elements (105a, 105b) between two neighbouring arrangements, together with the lattice structure of the fixing frame (107), individual filter chambers (113) are formed.

7. A plant (100) for filtering dusts, comprising - the filter module (1) according to one of claims 1 to 6, - a housing (3) which has a receptacle for the filter module (1), - a supply channel (5) arranged upstream of the receptacle for the filter module (1), - a suction device (7) arranged in the housing (3), which suction device is in flow connection with the filter module (1), - a discharge channel (9) arranged downstream of the suction device (7), - a pressure sensor arranged between the filter module (1) and the suction device (7), and - a switch box (13) that is electrically connected at least to the suction device (7) and the pressure sensor.

8. The plant (100) according to claim 7, which has a volume flow rate of 3,000 m3 / h to 4,000 m3 / h for a raw gas volume of up to 0.1 m3, wherein the system (100) is designed for a KSt value of up to 500 bar*m / s.

9. The plant (100) according to claim 7 or 8, further comprising - a free space (303) arranged within the housing (3) between the filter module (1) and the suction device (7), - a blower unit with a blower motor and a blower outlet, which is arranged in the free space (303) in a movable manner, wherein the blower outlet is arranged at the height of the filter module (1) and the blower unit is movable parallel to the filter module (1), - a dust-collecting device (17) arranged in the supply channel (5) below the receptacle for the filter module (1), - a shut-off slide valve arranged between the receptacle and the dust-collecting device (17).

10. The plant (100) according to one of claims 7 to 9, further comprising a decoupling module (19) for explosion decoupling of the plant (100) from the supply channel (5), which is arranged between the receptacle for the filter module (1) and the supply channel (5).

11. The plant (100) according to one of claims 7 to 10, wherein the discharge channel (9) arranged downstream of the suction device (7) is designed as a pressure relief.

12. The plant (100) according to one of claims 7 to 11, wherein the discharge channel (9), the switch box (13) and the decoupling module (19) are integrated in the housing (3), so that the system (100) is of explosion-proof design.

13. A plant network for filtering dusts, comprising - at least two systems (100) for filtering dusts according to one of claims 7 to 12, wherein the at least two plants (100) are arranged one above the other and are aligned with respect to one another such that the feed channels (5) are located one above the other, - a hopper unit which receives the feed channels (5) of the at least two plants (100) and decouples them from one another in terms of flow.

14. A method for separating dusts from a gas stream, comprising the steps of a) introducing the gas stream laden with dusts into a supply channel (5) of a plant (100) for filtering dusts according to one of Claims 7 to 11, b) drawing the dust-laden gas stream into a filter module (1) for dusts using a suction device (7) of the system (100) according to one of the claims 1 to 6, c) separating the dusts from the dust-laden gas stream in the filter module (1), the dusts being collected in a filter material (111) and the gas stream being discharged via a discharge duct (9) of the system (100), d) continuously recording the pressure profile of the gas stream downstream of the filter module (1), e) continuously measuring the flow rate in the system (100) by means of a flow sensor, f) suspending steps a), b) and c) when the pressure falls below a predetermined pressure, g) cleaning or exchanging the filter module (1), h) restarting the process with step a).