Reactor device for passivating a filter condensate, filter device for filtering particles from a raw gas stream, and method for operating a reactor device

Abstract

The invention relates to a reactor device (1) for carrying out a chemical reaction between a filter condensate (3) and an oxidizing agent to reduce the chemical reactivity of the filter condensate (3) in at least one passivation process, wherein the reactor device (1) has a reactor chamber (5) surrounded by a reactor housing (4) with a filter device connection (6) for establishing a flow connection between the reactor device (1) and a filter device (2) and a collection chamber connection (8) for establishing a flow connection between the reactor device (1) and a collection chamber (9) for receiving passivated filter condensate (3), wherein the reactor chamber (5) is further divided by a reactor bottom (40) into a reaction chamber (11) and a discharge chamber (12).In order to further develop the reactor facilities (1) known in the prior art, it is proposed that the reactor bottom (40) be designed to be movable between a first and a second operating position, wherein the reactor bottom (40) forms part of the reaction chamber (11) in the first operating position and part of the discharge chamber (12) in the second operating position and the subdivision can be removed in the course of moving the reactor bottom (40).

Description

field of technology

[0001] The invention initially relates to a reactor device for carrying out a chemical reaction between a filter condensate and an oxidizing agent for the purpose of reducing the chemical reactivity of the filter condensate in the context of at least one passivation process, wherein the reactor device has a reactor chamber surrounded by a reactor housing with a filter device connection for establishing a fluidic connection between the reactor device and a filter device and a collecting chamber connection for establishing a fluidic connection between the reactor device and a collecting chamber for receiving passivated filter condensate.

[0002] Furthermore, the invention relates to a filter device for filtering out particles from a raw gas stream, comprising a filter device having one or more filter elements on which filter condensate collects during filtering, and a reactor device for carrying out a chemical reaction between the filter condensate and an oxidizing agent to reduce a chemical reactivity of the filter condensate in the context of at least one passivation process, wherein the reactor device has a reactor chamber surrounded by a reactor housing with a filter device connection for establishing a fluidic connection between the reactor device and the filter device and a collection chamber connection for establishing a fluidic connection between the reactor device and a collection chamber for receiving passivated filter condensate,wherein the reactor device is further arranged below the filter device in order to enable transport of the filter condensate from the filter device into the reactor device using gravity, wherein the reactor device has an extension chamber into which the filter condensate can be introduced against gravity to assist passivation.

[0003] Furthermore, the invention relates to a method for passivating filter condensate in a reactor device having a reactor chamber, wherein the reactor chamber can be closed in a gas-tight manner and the passivation is carried out in the reactor chamber with a time-limited supply of oxidizing agent in a first passivation process. State of the art

[0004] Reactor devices of the aforementioned type are known in the art. These devices are used to passivate filter condensate, which is typically taken from a filter device. The reactor device is operated in particular in combination with an upstream filter device and a downstream collection chamber for receiving the passivated filter condensate.

[0005] A reactor device is known, for example, as a separable chamber of a filter device in which filter material is treated to reduce any remaining reactivity. Reference is made in this regard to DE 10 2021 116 264 A and WO 2022 / 268497 A1.

[0006] Regarding the background of the invention, it should be noted that the filter condensates passivated with such a reactor device are typically, but not exclusively, produced in metal printing processes, for example, in laser sintering or laser melting processes, or, for example, in so-called 3D laser printing systems. In such processes, process gas is fed to a pressure booth in a circulation process, which is then regenerated in a filter device to remove contaminants (e.g., smoke) that arise during the metal printing process, particularly due to the high heat exposure. The filter material collected in the filter device is still highly reactive and therefore poses the risk of catching fire or igniting fire-prone objects.

[0007] During the metal printing process, an inert gas, such as argon or nitrogen, is preferably introduced into the pressure booth as the process gas. This ensures that the atmosphere within the pressure booth contains no or essentially no oxygen, preventing a reaction. With regard to metal printing devices as such, reference is made to DE 10 2017 206 792 A1, for example. Filter devices for metal printing devices are described, for example, in DE 20 2012 013 036 U1.

[0008] The contaminants generated during the metal printing process are captured by a filter system to prevent them from escaping into the environment. The filter condensate typically consists of a highly reactive material. Accordingly, there is an increased risk of ignition during disposal when the protective gas atmosphere created by the inert process gas is left behind.

[0009] Furthermore, it is also known in the prior art to passivate the filter condensate using flame retardants, i.e., to convert it into a state in which it can no longer catch fire or ignite fire-prone objects. For passivation, disposable filters are used, for example, which are disposed of at a predetermined fill level. In particular, such disposable filters are flooded with water and / or oil, thereby achieving passivation. Flame retardants, such as lime or gas granules, can also be blown into the filter so that the entire surface of the filter is wetted and the flame retardants mix with the filter condensate on the filter. Summary of the invention

[0010] In view of the above-described state of the art, the task is to provide an alternative reactor device and an alternative process with which the filter condensate is safely passivated so that no problematic waste is generated.

[0011] A possible solution to the problem is provided by a reactor device in which the reactor space is divided by a reactor base into a reaction chamber and a discharge chamber, wherein the reactor base is designed to be displaceable between a first and a second operating position, wherein the reactor base forms part of the reaction chamber in the first operating position and part of the discharge chamber in the second operating position and the division can be removed during the displacement of the reactor base.

[0012] The reactor space can thus be divided by the reactor floor into a reaction chamber and a spatially separate discharge chamber. In one possible embodiment, the reactor floor is, for example, an opening flap arranged in a partition wall formed between the reaction chamber and the discharge chamber, which opening flap can be pivoted from a first operating position into a second operating position. In the first operating position, i.e. when the partition wall is closed, the reactor floor faces the interior of the reaction chamber and is thus part of the reaction chamber. In the second operating position, i.e. when the partition wall is open, the reactor floor is, however, pivoted into the interior of the discharge chamber, for example, with a rear side of the opening flap facing away from the reactor floor contacting, for example, an inner wall of the discharge chamber.

[0013] According to a further possible embodiment, the reactor base can, for example, be a slidingly or rotationally displaceable portion of the reactor housing, which can be moved from the reaction chamber into the discharge chamber. The reactor base can be flat or curved, in particular with respect to its peripheral edges, such that a shape-corresponding contact of the reactor base with the reactor housing of the reactor chamber results. It is preferably provided that the reaction chamber has the filter device connection and that the discharge chamber has the collection chamber connection. The filter condensate to be passivated can thus be fed from the filter device directly into the reaction chamber of the reactor chamber via the filter device connection, while the discharge chamber can discharge the passivated filter condensate to a subsequent collection chamber via the collection chamber connection.The inlet and outlet for the filter condensate are thus directly assigned to the respective corresponding chamber of the reactor space.

[0014] Furthermore, the reactor floor can have at least one receiving area for the filter condensate. The receiving area can preferably differ in shape from the other sub-areas of the reactor floor. For example, the receiving area is an indentation or material recess in the reactor floor in which the filter condensate can collect after being introduced into the reactor chamber or after swirling, or preferably collects, for example, due to the flow conditions and / or structural features of the reactor chamber.

[0015] According to one possible embodiment, it is proposed that the reactor base be part of a shaft arranged in the reactor chamber and rotatable relative to the reactor housing. The shaft can, in particular, be mounted on the reactor housing. The shaft is arranged within the reactor chamber and directly or indirectly connected to the inner wall of the reactor housing in such a way that the reactor chamber has two spatially separate chamber sections: the reaction chamber, in which the passivation reaction takes place, and the discharge chamber, which, after completion of the passivation process, receives the passivated filter condensate and discharges it to a collection chamber.

[0016] The shaft, or at least one receiving area for the filter condensate formed on its circumferential surface, is located in a first rotational position of the shaft within the reaction chamber and can be displaced into a second rotational position within the reactor housing by rotating the shaft such that the filter condensate located in the receiving area can pass from the reaction chamber into the discharge chamber. If the shaft has a plurality of receiving areas for the filter condensate distributed over the circumference, the shaft can also have a plurality of rotational positions in which a respective receiving area is located within the reaction chamber or at least partially within the discharge chamber of the reactor space.

[0017] The reactor base or shaft can be connected directly or indirectly to an inner wall of the reactor housing with the receiving area that receives the filter condensate, optionally with the interposition of a seal or a component acting as an adapter, for example, a bushing that will be proposed later. The reactor base or shaft spatially separates the reaction chamber containing the still-reactive filter condensate from the discharge chamber containing the passivated filter condensate, which provides the transition to a collection chamber for the passivated filter condensate.

[0018] The reactor device is preferably connected to the filter device via a flow channel with an airtight valve, in particular a disk valve. A valve is preferably also located between the reactor device and a collection chamber connected via its collection chamber connection. A further valve can be located downstream of this valve, which is open, for example, during operation of the reactor device and is only closed before the collection chamber is removed. The further valve thus serves as a convenient, but not absolutely necessary, addition to retain residues of the passivated filter condensate in the reactor device or a supply line of the collection chamber when the collection chamber is disconnected from the collection chamber connection.

[0019] After the chemically active filter condensate leaves the filter device, it first enters the reaction chamber of the reactor device via the filter device connection and collects, due to the effect of gravity, on the surface of the reactor base or shaft, namely in an area that provides a receiving area for the filter condensate. The receiving area can, for example, be an indentation, a material recess, a bore, or even an annular edge area of ​​a curvature, as will be explained in more detail later.

[0020] The spatial separation between the reaction chamber and the discharge chamber of the reactor space, for example, by contacting the shaft and the reactor housing, ensures that the filter condensate remains in the designated area, namely the reaction chamber, as long as passivation is not yet complete. This ensures that the filter condensate can only come into contact with oxidizing agents, especially oxygen, and react chemically within the reaction chamber. As long as it is still contained separately in the reaction chamber, the filter condensate cannot inadvertently enter other areas of the reactor facility, especially the discharge chamber, and react there in an uncontrolled manner, which could lead to damage to the reactor facility or the entire system comprising the filter facility, reactor facility, and collection chamber.

[0021] As soon as the filter condensate has collected within the reaction chamber, particularly in the receiving area, the valve between the filter device and the reactor device is closed. The valve can be provided, in particular, in the area of ​​the filter device connection. The reaction chamber is then evacuated until a predefined negative pressure is reached. An additional gas inlet valve is then opened, allowing ambient air, in particular from the immediate external environment of the reactor device, to flow into the reaction chamber.

[0022] Alternatively or additionally, pressurized air, which is preferably ultimately ambient air, can also be used. This can, for example, be compressed air from a conventional compressed air network of an operational facility into which the reactor device is integrated. However, again in addition to or as an alternative to the compressed air from the compressed air network, a compressed air reservoir can also be provided from which compressed air can be fed. The compressed air reservoir can in turn be charged from a compressed air network, as mentioned, or additionally or alternatively via a compressor. The ambient air or the oxygen it contains acts as an oxidizing agent for the passivation reaction of the filter condensate.The oxidizing agent can flow directly toward the collected filter condensate, particularly preferably directly into the receiving area, through a defined orientation of the gas inlet, for example, designed as a bore within the reactor housing. This swirls the filter condensate within the reaction chamber of the reactor device and preferably distributes it over the entire available volume. The reaction thus takes place not only within the receiving area, but rather within the preferably entire reaction chamber of the reactor device.

[0023] As soon as a defined pressure, in particular ambient pressure, is reached within the reaction chamber, the gas inlet valve closes, stopping the supply of oxidant. The process then preferably waits until the filter condensate has collected in the receiving area again. The passivation process can then be repeated, particularly if it is determined that the filter condensate is not yet fully passivated but continues to exhibit a certain degree of chemical reactivity. The relative state of the filter condensate can be determined, for example, by measuring a pressure or temperature within the reaction chamber. The measured value is compared, for example, with a reference value. The reference value can be a pressure or temperature within the reaction chamber before the oxidant flows in.If the temperature and / or pressure rises above the reference value as the oxidant flows into the reaction chamber, it can be assumed that the filter condensate is not yet fully or at least not sufficiently passivated. As soon as the temperature and / or pressure no longer rises as the oxidant flows in, the filter condensate has reached a safe passivation state. The relevant reference value, at which sufficient passivation can be assumed, can generally be specified by the manufacturer of the reactor equipment or by a user.

[0024] An alternative approach to controlling the passivation state of the filter condensate is to first determine and specify the amount of oxidizing agent required to reliably passivate the filter condensate. Based on this, the number of passivation cycles required to allow the required total amount of oxidizing agent to react with the filter condensate can then be determined.

[0025] Alternatively or additionally, the oxidizing agent can also be heated before flowing into the reactor device to stimulate a reaction in the filter condensate. This could, for example, initiate a passivation reaction early, thus shortening the reaction time within the reactor device. Heating the oxidizing agent can be achieved, for example, by equipping a wall of an oxidizing agent supply line with heating elements or by designing it as a heat exchanger. The temperature of the supplied oxidizing agent can, for example, be ambient temperature or an elevated temperature above the ambient temperature.

[0026] Alternatively or additionally, an ignition spark can be deliberately generated to initiate combustion and thus the reaction. This could be, for example, a piezoelectric spark generator, a spark plug, or ignition electrodes.

[0027] Once the desired, defined passivation state of the filter condensate has been achieved after one or more passivation cycles, it is preferable to wait again until the passivated filter condensate has settled in the receiving area. The reactor base is then moved from its previous, first operating position to a second operating position. According to an exemplary embodiment in which the reactor base is part of a rotatable shaft, the shaft is rotated by 90 degrees, for example. Subsequently, the valve(s) located between the reactor device and the collection chamber are opened, allowing the passivated filter condensate to flow from the discharge chamber of the reactor chamber into the collection chamber.

[0028] After removing the filter condensate from the reactor chamber's discharge chamber, the reactor floor or shaft, particularly the section containing the receiving area, can be cleaned. Such cleaning can be carried out using inert gas, in particular. Bearing points can also be cleaned. The reactor device is then ready for another passivation process, which is initiated by evacuating the reactor device's reaction chamber again.

[0029] An oil-lubricated vacuum pump can be used, in particular, to evacuate the reactor chamber. According to one possible design, the gas drawn from the reactor chamber can be filtered through an oil bath of the vacuum pump to separate dirt particles and parts of the filter condensate present in the evacuated gas. An oil filter is typically used to separate the dirt particles or filter condensate. This design has the particular advantage that particles whose passivation state is unclear are specifically extracted from the reactor chamber and conveyed into the oil of the vacuum pump, where the filter condensate is then finally passivated by the oil, thus reaching a safe state. The dirt particles or the passivated filter condensate are then disposed of via regular oil or oil filter changes.

[0030] An additional separator can also be installed upstream of the vacuum pump, which may be oil-lubricated, to further filter the gas as it is drawn in. This can potentially avoid the need for excessively frequent oil changes.

[0031] Furthermore, one or more bearing points of the vacuum pump can be specifically cleaned or protected from contamination using a gas stream, possibly also an inert gas. For this purpose, appropriate nozzles are preferably provided, suitably aligned with the bearing points.

[0032] Furthermore, with regard to a rotatable shaft, it is proposed that the shaft be mounted on the reactor housing of the reactor device. Bearing points for the shaft are thus preferably formed on the reactor housing. Particularly preferably, the reactor housing has two bearing points that are opposite one another with respect to a center of the reaction chamber and thus securely hold the shaft in position without the possibility of tilting.

[0033] With regard to the shaft, it is further proposed that it have different outer diameters along its axial extent. For example, an axial section of the shaft in the region of the bearing points can have a smaller diameter than a section of the shaft in the circumferential area, which includes the receiving area for the filter condensate. In particular, the size and shape of the shaft, in particular its circumferential contour, are matched to an internal shape of the reactor chamber, so that direct or indirect contact can occur between a partial area of ​​the shaft and partial areas of the inner wall of the reactor chamber in order to form the reaction chamber and spatially separate it from the discharge chamber and the reactor chamber. If necessary, additional sealing means can be provided between the shaft and the reactor housing.

[0034] It is further proposed that the reaction chamber have a bushing which is pressed, in particular by means of spring force, onto a circumferential portion of the shaft comprising the reactor base, said bushing connecting the shaft to the reactor housing, wherein more preferably the shaft is rotatable between a pass-through position and a shut-off position while maintaining contact with the bushing. The bushing thus forms an adapter part between the surface of the shaft and the inner wall of the reactor chamber. The bushing is designed, in particular, as a cylindrical component which is placed with a corresponding shape onto the circumferential surface of the shaft, namely where the receiving area for the filter condensate is provided. The wall of the bushing surrounds that circumferential portion of the shaft which has the receiving area for the filter condensate.Furthermore, the bushing is also particularly shaped to fit or integrate into the inner wall of the reactor housing with respect to its opposite end face.

[0035] To ensure a shape-corresponding engagement with the circumferential surface of the shaft, the bushing can, for example, have different lengths along its circumference, based on its axial length. According to one possible design, the contour of the end face of the bushing appears, for example, arc-shaped, in particular concave, when viewed in the axial direction of the shaft. Viewed in the direction of rotation of the shaft, i.e., orthogonal to the axis of rotation of the shaft, the contour of the end face of the bushing appears straight. It is essential that the shape of the end opening of the bushing corresponds to the shape of the circumferential surface of the shaft, so that a sealing engagement of the bushing against the shaft is achieved.

[0036] The bushing is preferably pressed onto the circumferential surface of the shaft by the restoring force of a spring element. This creates a spatial, but not necessarily gas-tight, separation of the reaction chamber from the discharge chamber of the reactor space. The spatial separation by means of the bushing, which preferably adjoins the shaft on the one hand and the inside of the reactor housing on the other hand in a shape corresponding to the shaft, ensures that the filter condensate remains specifically in the intended area, namely the reaction chamber, in order to react with oxidizing agent, preferably oxygen, only there. The filter condensate can therefore not inadvertently enter other areas of the reactor device. The spring element can preferably be designed as a helical spring, which rests against an end face of the bushing facing away from the shaft.Particularly preferably, the spring element enables rotation of the shaft about its axis of rotation while simultaneously maintaining contact between the surface of the shaft and the bushing, even when the shaft rotates away from the reactor housing and the bushing. It is understood that the helical spring mentioned as an example is only one possible embodiment of a spring element which presses the bushing against the circumferential surface of the shaft with a spring force. Alternatively, leaf springs or other spring elements can also be used. In principle, it is also possible to design the bushing itself as a spring element, for example using a spring-elastic but relatively rigid material. For example, the bushing can also be folded like an accordion.

[0037] A spring-loaded contact between the bushing and the shaft has the advantage of compensating for any wear or abrasion on the peripheral surface of the shaft and / or bushing caused by friction between the components rubbing against each other. The spring-loaded contact thus allows for automatic adjustment of the contact, compensating for any play.

[0038] It can further be provided that a longitudinal axis of the bushing is oriented orthogonally to a rotational axis of the shaft. According to this embodiment, an at least partially open end face of the bushing can be placed on the circumferential surface of the shaft in order to delimit the circumferential partial area with the receiving area for the filter condensate. The inner wall of the bushing simultaneously forms part of the inner wall of the reaction chamber, together with optionally other parts of the reactor housing. Thus, an inner wall of the reaction chamber is formed from the circumferential partial area of ​​the circumferential surface of the shaft enclosed by the bushing, the inner wall of the bushing itself, and optionally one or more partial areas of the inner wall of the reactor housing.

[0039] According to one possible embodiment, the at least one receiving area has a recess. The recess can, in particular, be a concave depression on the circumferential surface of the shaft. The recess forms a type of collecting tray for the filter condensate, which – following gravity – collects on the circumferential surface of the shaft. The particularly concave design of the recess ensures that, when oxidizing agent flows into the reaction chamber, the filter condensate is swirled up on the circumferential surface of the shaft and circulates within the reaction chamber, so that the filter condensate mixes with the oxidizing agent and thus preferably undergoes a particularly homogeneous reaction. This ensures that the filter condensate can be passivated particularly quickly and completely.In this context, it is particularly advantageous if gas inlet openings for admitting oxidizing agent into the reaction chamber are arranged in such a way that the oxidizing agent flows towards the receiving area and specifically swirls up the filter condensate out of the receiving area.

[0040] After completion of the passivation process, in particular after a plurality of passivation cycles, the shaft is rotated about its axis of rotation in order to remove the filter condensate located in the receiving area and transfer it to the discharge chamber of the reactor space. The rotation of the shaft causes a displacement of the receiving area of ​​the shaft relative to the bushing or relative to a portion of the inner wall of the reactor housing (particularly if no bushing is interposed). The rotation of the shaft creates a gap between the circumferential portion of the shaft containing the receiving area and the bushing or reactor housing that previously contacted this circumferential portion. This creates a flow connection between the reaction chamber and the discharge chamber of the reactor space, allowing the passivated filter condensate to flow from the reaction chamber into the discharge chamber.This is preferably supported by prior evacuation of the discharge chamber. The filter condensate subsequently located within the discharge chamber can then leave the discharge chamber via the collection chamber connection toward a connected collection chamber. To this end, it can preferably be provided that the reactor chamber, including the discharge chamber, is evacuated again. Furthermore, the shaft receiving area, in which the filter condensate previously collected, can also be blown clean with inert gas. For this purpose, appropriate valves are then opened.

[0041] If the shaft has a plurality of recesses formed successively in the circumferential direction, a first recess can, for example, be in a first rotational position in which the first recess within the reaction chamber is fluidically separated from the discharge chamber of the reactor space, while a second recess of the shaft is in a second rotational position in which the second recess has a flow connection to the discharge chamber, so that the second recess can be emptied into the discharge chamber of the reactor space.

[0042] According to an alternative embodiment, it can be provided that the at least one receiving area has a through-bore running transversely to the axis of rotation and a curvature formed on the at least one circumferential partial area of ​​the shaft and running transversely to a circumferential direction of the shaft. In particular, the curvature can be a convex elevation protruding radially from an end-side edge area of ​​the circumferential surface of the shaft. In contrast to the previous embodiment, the receiving area for the filter condensate is therefore not formed by a recess in the shaft material, i.e. not by a depression, but rather by a curvature running in the axial direction of the shaft. This curvature thus runs transversely to the already existing convex contour of a cylindrical shaft. In other words, the shaft therefore also has a curved contour when viewed orthogonally to the axis of rotation.In particular, the contour slopes downwards toward the end faces of the shaft. The shaft with the curvature also has a through-hole that runs through the shaft perpendicular to the axis of rotation. The through-hole does not penetrate the curvature, which runs perpendicular to the circumferential direction of the shaft.

[0043] According to a special design, the shaft has a curvature running transversely to the circumferential direction on two opposite circumferential sections. The curvatures are thus opposite each other with respect to the shaft's rotational axis and also with respect to the through hole.

[0044] The reaction chamber is emptied of filter condensate using the through-hole in such a way that, as the shaft rotates, the through-hole shifts relative to the filter condensate collected in the annular contact area between the inner wall of the bushing or the reactor housing and the circumferential surface of the shaft. As the rotating shaft continues to rotate, the filter condensate flows from the reaction chamber into the discharge chamber of the reactor space. This occurs by scraping off the filter condensate located at the edge of the curvature through the front edge area of ​​the bushing or a portion of the inner wall of the reactor housing corresponding to the edge area of ​​the curvature (provided no bushing is interposed). The filter condensate falls through the through-hole into the discharge chamber.

[0045] In this embodiment, it is particularly advantageous to provide one or more inlet openings for the oxidizing agent within the sleeve or reactor housing, through which the oxidizing agent can flow into the reaction chamber in the circumferential direction of the reaction chamber, in particular in the circumferential direction of the cylindrical sleeve. As a result, the filter condensate located at the annular edge of the curvature (which collects at the edge of the sleeve due to the curvature) is conveyed into the reaction chamber in the circumferential direction of the reaction chamber and away from the shaft, in particular following a spiral flow path.

[0046] In both the first-mentioned embodiment with a recess in at least one circumferential portion of the shaft, and the second, last-mentioned embodiment with a curvature and through-bore formed in the circumferential portion, either a single receiving area for filter condensate can be provided along the circumference of the shaft, or multiple receiving areas can be provided. If multiple receiving areas are provided, this has the advantage that, for example, a first receiving area for receiving filter condensate faces into the reaction chamber, while a second receiving area is located at least partially outside the reaction chamber and already has a flow connection to the discharge chamber of the reactor space.Furthermore, in the case of multiple receiving areas, it is advantageous that the shaft does not have to be rotated back and forth or undergo a 360-degree rotation between two passivation cycles. Instead, with, for example, four receiving areas along the circumference, only a single rotation of 90 degrees is required to start a new passivation cycle. Thus, one, two, three, four, or even more receiving areas can be provided in the circumferential direction of the shaft. In the case of the embodiment with a curvature and a through hole, two receiving areas that are mirror-symmetrically opposite one another with respect to the shaft's rotational axis are particularly recommended.

[0047] According to a preferred embodiment, it can be provided that the reactor housing has a particularly tubular extension chamber into which the filter condensate can be introduced against gravity to assist passivation, wherein the extension chamber is designed as a dead space into which the filter condensate can be introduced, flowing at a height past the filter device connection, solely for passivation. Due to its design as a dead space, the extension chamber only has a filter condensate inlet and no filter condensate outlet. The extension chamber is arranged relative to the reaction chamber such that the filter condensate swirled up in the reaction chamber rises into the extension chamber, but does not flow into the filter device connection, but merely flows past it. The volume of the extension chamber advantageously supplements the volume of the reaction chamber, so that more ambient air orOxidizing agent can be provided for the passivation of the filter condensate.

[0048] If a bushing is arranged between the shaft and the reactor housing, it can be provided in particular that the extension chamber connects to the reaction chamber, in particular beyond the bushing. In this case, the extension chamber is designed to be spatially separated from the filter device connection. The extension chamber forms an enlargement of the volume of the reaction space provided by the reaction chamber for the passivation of the filter condensate. It is particularly preferred that the extension chamber does not connect to the reaction chamber via the filter device connection, but is spatially separated from it, so that the reaction chamber together with the extension chamber forms a single volume, to which the filter device connection is connected in order to transfer filter condensate from the filter device into this shared volume.The expansion chamber can, for example, be formed by a tubular flow channel that is closed at one end. For example, the expansion chamber is a tube with a pipe end that has a flange with integrated sensors, such as a previously proposed temperature sensor and / or pressure sensor. The expansion chamber extends the reaction space for the passivation process by providing a larger air volume in which the filter condensate can be swirled. The passivation process can thus proceed significantly faster than with a smaller available air space.

[0049] It is further proposed that the reaction chamber and / or the expansion chamber and / or the bushing have at least one temperature sensor and / or at least one pressure sensor and / or at least one connection for introducing gas into the reaction chamber. In particular, it can be provided that a connection for introducing gas is oriented relative to the receiving area, preferably inclined relative to the reactor floor, such that filter condensate located in the receiving area is swirled within the reaction chamber and / or within the expansion chamber.

[0050] The at least one temperature sensor and / or pressure sensor serves to monitor the passivation process within the reaction chamber. If the measured pressure or temperature within the reaction chamber exceeds a defined reference value or reference range, it can be assumed that the passivation of the filter condensate is not yet complete and that residual chemical reactivity still exists, which poses a fire hazard. The at least one temperature sensor or the at least one pressure sensor can be provided at different locations within the reaction chamber. For example, an arrangement can be provided in the region of the receiving area for the filter condensate or in the region of a bushing connecting a shaft to the reactor housing.Alternatively, arrangements further away from this are also possible, for example in an extension chamber which adjoins the reaction chamber, namely in a part of the reaction chamber which is opposite the receiving area for the filter condensate.

[0051] As previously proposed, a connection for introducing oxidant into the reaction chamber is preferably oriented relative to the receiving area of ​​the shaft such that filter condensate located in the receiving area is impacted by the introduced oxidant as early as possible and can thus be swirled within the reaction chamber and / or the expansion chamber. Preferably, an inlet opening, for example a valve, is inclined relative to the shaft so that the oxidant is introduced toward the receiving area.

[0052] Furthermore, the reactor device can have a portioning device connected to the filter device connection of the reactor device, which is configured to separate a first portion of a total amount of filter condensate from at least a second portion of the total amount of filter condensate and transfer it into the reaction chamber of the reactor device. The portioning device can, in particular, be a lock delimited by valves or a rotary valve. In the case of a rotary valve, the portioning device can preferably have a rotary valve housing and a rotary valve, wherein the rotary valve is closed at least on one end face by a disc axially loaded with a spring force.

[0053] The portioning device portions the filter condensate flowing from the filter device so that it is transferred in separate portions into the reactor chamber of the reactor device. The portioning device can preferably be actuated multiple times to transfer the filter condensate to be passivated in portions into the reactor chamber, where it can react with the oxidizing agent. A valve is preferably located between the portioning device and the reactor chamber.

[0054] According to a particularly simple embodiment, the portioning device can be designed in the manner of a lock delimited by valves. The arrangement can simply consist of two valves and a space arranged between them. The space between the valves can thus determine the amount determined by the portioning device per portion stroke. However, the use of a rotary valve is particularly preferred, which has a rotary valve housing and a rotary valve that can be rotated relative to it and that can have one or more rotary valve chambers. For example, a rotary valve chamber can extend over a certain angular range, for example 90° or 180°, and in the wider angular range there can be a closed configuration, so that only one rotary valve chamber is formed. Accordingly, the closed region can alternatively be formed as one or more rotary valve chambers to form multiple rotary valve chambers.The rotary valve is preferably aligned such that it is slightly inclined in a defined starting position, i.e. the bottom surface of a rotary valve chamber is not oriented horizontally but slightly inclined so that filter condensate in the rotary valve chamber can escape from the cell chamber under the force of gravity. This ensures that an entire portioned amount of filter condensate can be conveyed out of the respective rotary valve chamber in a controlled manner and that no part of the filter condensate remains in the rotary valve. The portioning device is preferably designed such that only part of the rotary valve rests against the rotary valve housing to prevent filter condensate from becoming jammed between the rotary valve and the rotary valve housing.If filter condensate collects in the clearance between the cell wheel and the cell wheel housing, it can be released by over-turning it by more than 180 degrees.

[0055] According to a particularly preferred embodiment, a disc can be pressed axially against the cellular wheel by means of a spring element, thus closing one end of the cellular wheel. This preferably ensures a form-fitting and force-locking connection between the disc and the cellular wheel. The disc forms part of the cellular wheel housing. The spring-loaded disc also determines the axial position of the cellular wheel. At the same time, the disc prevents filter condensate from escaping from a designated area. Furthermore, if parts of the cellular wheel or the cellular wheel housing wear out due to friction between parts, the position of the disc is automatically adjusted. In addition, the pressing of the disc by a spring element allows the cellular wheel to continue rotating relative to the cellular wheel housing.

[0056] One or more of the bearings in the rotary vane housing, in particular the bearings of the rotary vane in the rotary vane housing, can also be flushed with a gas, in particular the aforementioned inert gas. For this purpose, one or more suitable nozzles are provided, which can then be directed specifically at the bearing.

[0057] Furthermore, a reactor device for carrying out a chemical reaction between a filter condensate and an oxidizing agent for reducing a chemical reactivity of the filter condensate in the context of at least one passivation process is proposed, wherein the reactor device has a reactor chamber surrounded by a reactor housing with a filter device connection for establishing a fluidic connection between the reactor device and a filter device and a collection chamber connection for establishing a fluidic connection between the reactor device and a collection chamber for receiving passivated filter condensate, wherein the reactor chamber has a rotatable shaft and a bushing which has an end region pressed onto a circumferential part of the shaft and which connects the shaft to the reactor housing to form a reaction chamber which is spatially separated from a discharge chamber of the reactor chamber.The proposed rotatable shaft is particularly suitable for conveying filter condensate collected on a circumferential section of the shaft from the reaction chamber to the discharge chamber. The conveying takes place by rotating the shaft about its axis of rotation. The shape-corresponding contact of the bushing on the respective circumferential section of the shaft - together with the reactor housing - preferably encloses a partial volume of the reactor space of the reactor device, in which the filter condensate can be passivated. Upon rotation of the shaft, the bushing is assigned to a respective circumferential section of the shaft following in the circumferential direction. Particularly preferably, the shaft has a receiving area for the filter condensate on one or more circumferential sections, for example an indentation, in which the filter condensate can collect.This recess is then rotated from the reaction chamber into the discharge chamber as the shaft rotates, where emptying can take place. During the rotation, the spatial separation between the reaction chamber and the discharge chamber is temporarily removed.

[0058] In particular, the rotatable shaft can be designed to be rotatable between a first and a second operating position, wherein the circumferential portion of the shaft forms part of the reaction chamber in the first operating position and part of the discharge chamber in the second operating position, wherein the separation between the reaction chamber and the discharge chamber can be eliminated during rotation of the shaft.

[0059] In addition to the previously proposed reactor device, a filter device for filtering out particles from a raw gas stream is also proposed, wherein the filter device is designed with a filter device having one or more filter elements on which filter condensate collects during filtering, and a reactor device for carrying out a chemical reaction between the filter condensate and an oxidizing agent to reduce a chemical reactivity of the filter condensate in the context of at least one passivation process,wherein the reactor device (1) has a reactor chamber surrounded by a reactor housing with a filter device connection for establishing a fluidic connection between the reactor device and the filter device and a collection chamber connection for establishing a fluidic connection between the reactor device and a collection chamber for receiving passivated filter condensate, wherein the reactor device is further arranged below the filter device in order to enable transport of the filter condensate from the filter device into the reactor device using gravity, wherein the reactor device has an extension chamber into which the filter condensate can be brought against gravity to assist passivation, wherein the filter device connection and the collection chamber connection can be closed to carry out the passivation process,and wherein the expansion chamber is designed as a dead space into which the filter condensate can be brought, flowing past the filter device connection at a higher level, only for passivation.

[0060] The proposed filter device comprises a reactor device, which can be designed according to one or more of the embodiments previously presented as examples. A filter device is arranged upstream of the reactor device. Furthermore, a portioning device can also be provided between the filter device and the reactor device, for example, which portions the filter condensate collected in the filter device and forwards it to the reactor device.

[0061] The filter device captures, for example, impurities arising during a metal printing process, so that they are removed from the process gas, which is essentially and preferably conducted as recirculated air, and captured as filter condensate in a corresponding filter. The proposed filter device can have only one or several such filter devices. It is also possible to use several filter units arranged in parallel, which are integrated into the filter device, for example, via a common inlet and outlet valve.

[0062] Furthermore, a method for passivating filter condensate in a reactor device having a reactor chamber is proposed, wherein the reactor chamber can be closed in a gas-tight manner and the passivation is carried out in the reactor chamber with a time-limited supply of oxidizing agent in a first passivation process, wherein the passivation is repeated in a second passivation process or in further passivation processes in accordance with a pressure reached in the reactor chamber in the first passivation process or a temperature reached in the reactor chamber in the first passivation process.

[0063] The second or subsequent passivation process can preferably be carried out after the filter condensate has collected again on a reactor floor of the reactor chamber. For each passivation process, oxidizing agent is preferably added to the reactor chamber again, with the addition of oxidizing agent being used to resuspend the filter condensate.

[0064] The proposed method preferably includes filling filter condensate into a reaction chamber of the reactor space, introducing oxidizing agent into the reaction chamber, mixing the filter condensate with the oxidizing agent to reduce the chemical reactivity of the filter condensate, moving a reactor base dividing the reactor space into the reaction chamber and a discharge chamber from a first operating position, in which the reactor base forms part of the reaction chamber, to a second operating position, in which the reactor base forms part of the discharge chamber, wherein the division is removed during the movement of the reactor base, and emptying the filter condensate located in the reaction chamber into the discharge chamber and / or into a collection chamber connected to the discharge chamber.

[0065] As proposed, the process is carried out in such a way that the filter condensate is first introduced into the reaction chamber of the reactor space. This can be achieved, for example, with the aid of a previously proposed portioning device, which is arranged in a flow channel between a filter device and the reactor device. The filter device filters out impurities arising from a process gas, for example during metal printing processes, which are still highly reactive and thus pose a risk of catching fire or igniting fire-prone objects. The filter device absorbs and stores these impurities before they are passivated by a reactor device proposed here. For example, during filter cleaning, the filter condensate can fall into a rotary valve chamber of the rotary valve or directly into the reaction chamber of the reactor device.Alternatively or additionally, a pressure difference can be created between the interior of the reaction chamber or the portioning device and the filter device to transport the filter condensate into the reaction chamber. Alternatively or additionally, the filter condensate can also be supported by a gas stream, for example, an inert gas stream, flowing from the filter device into the reactor device. Finally, the filter condensate could also be sucked from the filter device or the portioning device into the reaction chamber of the reactor device.

[0066] After the filter condensate has been transferred to the reaction chamber, it is preferably first waited until the filter condensate has almost completely collected in the designated receiving area of ​​the shaft. Then, an oxidizing agent, for example ambient air, is introduced into the reaction chamber, whereby the introduction particularly preferably takes place via nozzles or openings that direct the oxidizing agent directly towards the receiving area. In the receiving area or in the vicinity of the receiving area, the filter condensate is then mixed with the oxidizing agent, whereby the filter condensate is swirled up, in particular throughout the entire gas volume of the reaction chamber or, if applicable, an additional expansion chamber. The mixing of the filter condensate with the oxidizing agent begins a chemical reaction, which can optionally be promoted further by prior heating of the oxidizing agent.The chemical reaction reduces the reactivity of the filter condensate. Complete passivation of the filter condensate may not require a single passivation cycle; rather, several consecutive passivation cycles may be necessary to bring the reactivity of the filter condensate below a previously defined reference value or reference range for residual reactivity. This reference value or reference range indicates a residual reactivity that can no longer lead to a fire in the filter condensate or pose a fire hazard to other objects.

[0067] After one or more consecutive passivation processes, the system waits again until the filter condensate collects in the receiving area of ​​the shaft. The shaft is then rotated into a rotational position in which the receiving area is located at least partially outside the reaction chamber and has a flow connection to the discharge chamber of the reactor chamber. The passivated filter condensate can flow from the reaction chamber into the discharge chamber via this flow connection. This preferably results in complete emptying of the filter condensate located in the receiving area into the discharge chamber of the reactor chamber and / or into a collection chamber connected to the discharge chamber via the collection chamber connection.

[0068] To check the chemical reactivity of the filter condensate within the reaction chamber, it may be provided, in particular, that a temperature and / or pressure is measured at one or more locations. This temperature or pressure provides information about the remaining reactivity of the filter condensate, since the temperature or pressure increases when still chemically reactive filter condensate comes into contact with an oxidizing agent.

[0069] In particular in this context, it is further proposed that after mixing the filter condensate with the oxidizing agent, a temperature and / or a pressure within the reaction chamber and / or within the extension chamber is detected and compared with a reference value, wherein in the event that the temperature and / or the pressure is above the reference value, oxidizing agent is again introduced into the reaction chamber without removing the filter condensate from the reaction chamber or introducing new filter condensate into the reaction chamber, so that the same filter condensate is again subjected to a passivation process, and wherein the receiving area is only rotated at least partially out of the reaction chamber when the temperature and / or the pressure is below the reference value.

[0070] The passivation process can be repeated until the filter condensate has reached the desired passivation state. As suggested, the passivation state is determined via temperature and / or pressure measurement. The temperature and / or pressure measured within the reaction chamber, the bushing, or the expansion chamber during the inflow of oxidant can be used as a reference. If the temperature and / or pressure rises during the inflow of the oxidant, it can be assumed that the filter condensate has not yet been sufficiently passivated. However, as soon as the temperature and / or pressure no longer rises during the inflow of the oxidant, the filter condensate has typically reached a safe passivation state.

[0071] As an alternative to the aforementioned procedure, the amount of oxidant required to reliably passivate the filter condensate could be measured. This can then be used to calculate the number of individual additions of oxidant to the reaction chamber required to completely passivate the filter condensate. Additionally, the oxidant can be heated before flowing into the reactor chamber to stimulate the chemical reaction. This allows a reaction to be started or completed more quickly, if necessary. The temperature of the added oxidant can be, for example, ambient temperature or an even higher temperature. Short description of the drawings

[0072] The invention is explained in more detail below using exemplary embodiments. They show: Fig. 1 a system with a filter device, a portioning device and a reactor device; Fig. 2 the portioning device according to a longitudinal section through level II in Fig. 1; Fig. 3 a longitudinal section along line III in Fig. 2; Fig. 4 a longitudinal section according to level IV of the Fig. 1 reactor device; Fig. 5 a longitudinal section along the line V in Fig. 4; Fig. 6 the reactor facility according to Fig. 5 with a second rotational position of the shaft; Fig. 7 the reactor facility according to Fig. 6 with a subsequent rotational position of the shaft; Fig. 8 shows another embodiment of a shaft of the reactor chamber; Fig. 9 a section along the line IX in Fig. 8; Fig. 10 the reactor facility according to Fig. 9 with the shaft in a second position; Fig. 11 the reactor facility according to Fig. 10 with the shaft in a third rotational position; Fig. 12 the reactor device with an expansion chamber. Description of the embodiments

[0073] Fig. 1 shows a merely exemplary filter device with a filter device 2, a portioning device 7 and a reactor device 1. The filter device is, for example, connected downstream of a metal printing device (not shown) in order to filter contaminated process gas in a metal printing process and to passivate the filter condensate 3 collected within the filter device 2 by means of the reactor device 1, so that the chemical reactivity of the filter condensate 3 is no longer sufficient to ignite upon contact with oxygen or to ignite fire-prone objects.

[0074] The system presented can also be used for other industrial facilities that produce reactive filter condensate, rather than in conjunction with metal pressure equipment. The exemplary configuration shown below, particularly of the reactor device 1 and the portioning device 7, remains unaffected.

[0075] During a metal printing process, for example, process gas regeneration preferably takes place in a pressure booth. For this purpose, the process gas, for example, a protective gas such as argon or nitrogen, is blown into the pressure booth and then extracted again. A pump or a blower designed as a side-channel compressor can be used for this purpose. The extracted process gas is filtered within the filter device 2 and freed of contaminants, which subsequently form, among other things, the filter condensate 3.

[0076] With regard to a method for cleaning a filter of the filter device 2 as well as the filter device 2 itself, reference is made to the document DE 10 2019 132 349 A1 (US 2022 / 0362691 A1) merely by way of example. The content of this patent application is hereby incorporated in its entirety into the disclosure of the present invention, also for the purpose of incorporating features of this patent application into the claims of the present invention.

[0077] To clean the filter of the filter device 2 and to remove the filter condensate 3 that has settled on the filter during filtration of the process gas, the filter device 2 can be put into regeneration mode. For this purpose, the filter device 2 can first be removed from a process gas flow and cleaned, for example, using a separate pump or a side channel compressor, which generates negative pressure within the filter device 2. After a defined pressure is reached, a flushing medium, for example, is directed onto the filter wall to flow through the filter wall in a flow direction opposite to that of a filtering process. For a detailed explanation of the filtering process and regeneration process of such a filter device 2, reference is made, for example, to the document DE 10 2021 116 264 A (also published as WO 2022 / 268497 A1).The content of this patent application is hereby incorporated in its entirety into the disclosure of the present invention, also for the purpose of incorporating features of this patent application into claims of the present invention.

[0078] The filter device 2 is connected to the reactor device 1 or the portioning device 7 by means of an airtight valve 32, here for example a disk valve. Behind the portioning device 7, i.e. between the portioning device 7 and the reactor device 1, there is a further valve 33, which here is also designed as a disk valve. During filter cleaning, the filter condensate 3 is conveyed through the open valve 32 into the portioning device 7. The valve 32 is then closed and the reactor device 1 is evacuated with the valve 33 open down to the blocked valve 32. The portioning device 7 is then actuated so that the filter condensate 3 is transported into the reactor device 1.Within the reactor device 1, the filter condensate 3 is then treated in a passivation process until its chemical reactivity has fallen below a previously defined reference value or reference range and no longer poses a fire hazard. Before the passivation process is carried out, the valve 33 is closed and ambient air is preferably introduced into the reactor device 1 as an oxidizing agent.

[0079] After the passivation process is complete, another valve 34 located downstream of the reactor device 1 is opened to convey the passivated filter condensate 3 from the reactor device 1 into a collection chamber 9. Another valve 35 is located downstream of the valve 34 between the reactor device 1 and the collection chamber 9. This valve 35 can be closed if the collection chamber 9 is to be removed from the system. The valve 35 thus serves as an additional safety device. In principle, however, this valve 35 can be omitted, since the preceding valve 34 already provides sufficient protection against the ingress of air into the reactor device 1.

[0080] With reference to the Fig. 2 and Fig. 3, the portioning device 7, which is arranged upstream of the reactor device 1, will now be explained. The portioning device 7 is designed here merely as an example as a rotary valve. The portioning device 7 accordingly has a rotary valve housing 27 and a rotary valve 28 rotatably mounted in the rotary valve housing 27. The rotary valve 28 preferably has a plurality of rotary valve chambers 31, for example two, three, four or more rotary valve chambers 31, which are arranged one behind the other in the direction of rotation of the rotary valve 28. The rotary valve 28 has two opposite end faces 29, one of which is supported against the rotary valve housing 27 and the other preferably against a disk 30.The disc 30 is preferably acted upon by the restoring force of a spring element 36, which acts in an axial direction relative to a rotational axis 37 of the cellular wheel 28 and thus presses the disc 30 against the adjacent end face 29 of the cellular wheel 28. The force-locking connection acting in the axial direction of the rotational axis 37 of the cellular wheel 28 between the disc 30 and the cellular wheel 28 and also between the cellular wheel 28 and an adjacent housing wall of the cellular wheel housing 27 ensures that filter condensate 3 cannot escape from the cellular wheel chambers 31 of the cellular wheel lock into the environment. In addition, the position of the disc 30 is shifted or adjusted if material wear occurs due to friction of the cellular wheel 28 on the disc 30.The spring element 36 thus automatically adjusts the position of the disc 30, whereby the spring force of the spring element 36 continues to allow rotation of the cell wheel 28 relative to the cell wheel housing 27 on the one hand and the disc 30 on the other hand.

[0081] Although not shown here, a sluice consisting of two valves and a space arranged between them can also be used as the portioning device 7 instead of the illustrated rotary valve. The space between the valves determines the amount of filter condensate 3 portioned by the portioning device 7 per portion stroke. Furthermore, other embodiments of portioning devices 7 are also conceivable, which can be used in conjunction with the reactor device 1. The functioning of the reactor device 1 is not affected by this.

[0082] The Fig. 2 and Fig. 3 The portioning device 7, designed as a rotary valve, functions in such a way that initially a portion of the total amount of filter condensate 3 located in the filter device 2 is taken up into a first rotary valve chamber 31 of the rotary valve 28. For this purpose, the valve 32, which is arranged between the filter device 2 and the portioning device 7, is first opened so that the filter condensate 3 can fall through the opened valve 32 into the rotary valve. Subsequently, the valve 32 is closed, and the portioning device 7 is evacuated. The evacuation of the portioning device 7 preferably takes place simultaneously with the evacuation of the reactor device 1 with the valve 33 located between the portioning device 7 and the reactor device 1 open.After evacuation, the cell wheel 28 of the portioning device 7 is rotated about the rotation axis 37, whereby the filter condensate 3 stored in one or more cell wheel chambers 31 is transported into the reactor chamber 5 of the reactor device 1.

[0083] As can be seen in particular from the Fig. 3, the cellular wheel 28 here has, for example, only two cellular wheel chambers 31, which are opposite one another with respect to the rotation axis 37. While a first, with respect to the Fig. 3, the upper cell wheel chamber 31 is filled with filter condensate 3, the opposite, lower cell wheel chamber 31 is emptied in the direction of the reactor device 1.

[0084] As can also be seen, the portioning device 7 is preferably adjusted such that the cell wheel 28, in an initial position in which one of the cell wheel chambers 31 is being filled, is slightly inclined, so that a chamber bottom of the cell wheel chamber 31 is not oriented horizontally. This can contribute to the complete emptying of the cell wheel chamber 31 upon rotation of the cell wheel 28 by 180 degrees, and no portions of the filter condensate 3 remain in the portioning device 7. If, moreover, partial quantities of filter condensate 3 are located in a clearance between the cell wheel 28 and the cell wheel housing 27, these can be released by over-rotating by more than 180 degrees. It is also possible to assist the transport of the filter condensate 3 with a gas stream. According to a further possibility, the valve 32 could also be opened first and the valve 33 closed first.Then, only the reactor device 1 could be evacuated, without simultaneously evacuating the portioning device 7. Upon actuation of the rotary valve, the filter condensate 3 would then fall onto the closed valve 33 and, after opening the valve 33, would be sucked into the reactor device 1 until pressure equalization occurs between the filter device 2 and the reactor device 1.

[0085] In all described embodiments, the storage locations of the portioning device 7 can be flushed with a protective gas after the filter condensate 3 has been discharged into the reactor device 1. This cleans the storage locations, and any filter condensate 3 that could not reach the reactor device 1 is transported into the reactor device 1.

[0086] After the filter condensate 3 has left the portioning device 7, it enters the reactor device 1. As can be seen from Fig. 1, the reactor device 1 has a filter device connection 6, through which the filter condensate 3 can flow into the reactor device 1. At a lower end region opposite the filter device connection 6, the reactor device 1 similarly has a collection chamber connection 8, which is connected to the collection chamber 9, which ultimately collects the passivated filter condensate 3. The collection chamber 9 can be separated from the reactor device 1 in order to be able to dispose of the filter condensate 3 contained therein. The reactor device 1 further has an extension chamber 23 (see Fig. 1 and Fig. 12), the function of which will be explained in more detail later. The expansion chamber 23 has a closure 38, here, for example, in the form of a flange.

[0087] With reference to the Fig. 4 to 7, a first embodiment of a possible reactor device 1 is first described.

[0088] The reactor device 1 has a reactor housing 4 in which a reactor chamber 5 is formed. On the reactor housing 4, for example, a rotatable shaft 10 is mounted, which passes through the reactor chamber 5 and, with respect to the Fig. 4 and Fig. 5, the shaft 10 contacts a portion of the reactor housing 4, so that the reactor chamber 5 is divided by the shaft 10 into a reaction chamber 11 and a discharge chamber 12. A portion of the circumferential surface 14 of the shaft 10 forms a reactor base 40 for the reaction chamber 11.

[0089] As an alternative to a rotatable shaft 10, a division of the reactor space 5 into a reaction chamber 11 and a discharge chamber 12 could also be achieved by other structural measures, for example by a flap forming the reactor floor 40 of the reaction chamber 11 or a sliding housing section of the reactor housing 4.

[0090] To achieve contact between the circumferential surface 14 and the inner wall of the reactor housing 4, the shaft 10 has, for example, different outer diameters along its longitudinal extent, i.e., parallel to its rotational axis 18. A circumferential portion 13 with a largest diameter can be sealed from the reactor housing 4 by a bushing 16. The bushing 16 can be pressed onto the circumferential surface 14 of the shaft 10 by a spring element 39. This creates a connection to the reactor housing 4, which simultaneously separates the reaction chamber 11 and the discharge chamber 12 of the reactor space 5.

[0091] The bushing 16 can be designed as a cylindrical hollow body whose longitudinal axis 17 is orthogonal to the rotation axis 18 of the shaft 10.

[0092] The peripheral portion 13 of the shaft 10 projecting into the reaction chamber 11 has a receiving area 15 for filter condensate 3 filled into the reactor device 1. The receiving area 15 is, for example, a concave material recess.

[0093] As can be seen particularly from the Fig. 5 to 7, a total of four such receiving regions 15 for the filter condensate 3 are preferably formed over the circumferential surface 14 of the shaft 10. Two receiving regions 15 can each be located opposite one another with respect to the axis of rotation 18 of the shaft 10. By each 90-degree rotation about the axis of rotation 18 of the shaft 10, a different receiving region 15 of a different circumferential partial region 13 of the shaft 10 can always be displaced into the reaction chamber 11. The respective circumferential partial region 13, together with the inner wall of the bushing 16 and the remaining inner wall of the reactor housing 4, forms the reaction chamber 11. At least one connection 26 can open into the reaction chamber 11, here for example two connections 26, via which oxidizing agent can be introduced into the reaction chamber 11. The oxidizing agent here is oxygen or oxygen-containing ambient air.

[0094] As further shown in the Fig. As can be seen in Figures 5 to 7, the reaction chamber 11 can further comprise at least one temperature sensor 24 and at least one pressure sensor 25, which are configured via an evaluation device of the reactor device 1, for example a computer processor, so that a temperature or a pressure within the reaction chamber 11 can be measured. This serves - as will be explained below - to monitor a passivation process of filter condensate 3 within the reactor device 1.

[0095] The reaction chamber 11 is by means of the Fig. 1 shown expansion chamber 23 with respect to the jacketed gas volume.

[0096] The operation of the reactor device 1 according to this first embodiment ( Fig. 4 to 7) is now presented below.

[0097] If wave 10 is in the example in Fig. 4, the filter condensate 3 passes from the portioning device 7 into the reaction chamber 11, which is spatially separated from the discharge chamber 12 by the form-fitting and force-fitting contact of the bushing 16 with the circumferential section 13 of the shaft 10. The spatial separation ensures that the filter condensate 3 remains only in the reaction chamber 11 of the reactor space 5 as long as it has not yet been passivated. As soon as the filter condensate 3 has collected in the concave receiving area 15 of the circumferential surface 14 of the shaft 10 due to the effect of gravity, the valve 33 located between the reactor device 1 and the portioning device 7 is closed. The reaction chamber 11 is then evacuated, preferably together with the tubular expansion chamber 23, until a predefined pressure is reached.Air is then introduced into the reaction chamber 11 via the connections 26 from the immediate external environment of the reactor device 1. The connections 26 here are, for example, small bores or valves in the bushing 16, which are oriented obliquely to the longitudinal axis 17 of the bushing 16, so that the inflowing ambient air preferably and essentially in a straight line directly hits the receiving area 15 of the shaft 10. As a result, the filter condensate 3 collected in the receiving area 15 is swirled within the reaction chamber 11 and optionally within the extension chamber 23 and transported upwards, i.e. optionally in the direction of the extension chamber 23. As soon as a predefined pressure or the ambient pressure within the reaction chamber 11 or within the extension chamber 23 is reached (which can be measured by means of the pressure sensor 25), the supply of oxidant through the connections 26 is stopped.Then, again, wait until the filter condensate 3 has collected in the receiving area 15 of the shaft 10.

[0098] The passivation cycle described above can be repeated until the filter condensate 3 has reached a predefined desired passivation state. The passivation state can be determined by measuring a temperature or a pressure within the reaction chamber 11 or the expansion chamber 23. For this purpose, a temperature or pressure measurement is taken during or shortly after the oxidizing agent flows into the reaction chamber 11. If the temperature and / or pressure rises above a specified reference value or reference range, it can be concluded that the filter condensate 3 is not yet sufficiently passivated, i.e., still has residual chemical reactivity that poses a fire hazard.Therefore, the previously described passivation cycle is performed a second time by again bringing the same portion of filter condensate 3 located in the reaction chamber 11 into contact with the oxidizing agent. As soon as the temperature and / or pressure no longer increases, or at least no longer increases significantly, during the inflow of the oxidizing agent, the filter condensate 3 has reached a thus defined safe passivation state. The passivated filter condensate 3 can then be transferred from the reaction chamber 11 to the discharge chamber 12 of the reactor device 1.

[0099] Alternatively, to ensure complete passivation of the filter condensate 3, it is possible to determine in advance the required amount of oxidizing agent to completely passivate the filter condensate 3 and then calculate the number of passivation cycles necessary to passivate the total amount of filter condensate 3 over several consecutive passivation cycles. The reaction can be assisted, if necessary, by heating the oxidizing agent before it flows into the reaction chamber 11. This can stimulate a reaction of the filter condensate 3, so that passivation is started early and / or completed more quickly. The heating of the oxidizing agent can be achieved, for example, with the aid of heating elements that heat a wall of a reaction chamber feed line.Preferably, for example, it is also possible to design a wall of a reaction chamber supply line as a heat exchanger, e.g., by passing a warm liquid through a cavity in the wall. Alternatively, it is also possible to heat the oxidizing agent in a separate vessel or space outside the supply lines of the reactor device.

[0100] As soon as the desired passivation state of the filter condensate 3 is reached and the filter condensate 3 has collected at the intended position, namely the receiving area 15 of the shaft 10, the shaft 10 is rotated by 90 degrees around the rotation axis 18 in the illustrated embodiment. In doing so, first (among other things) the Fig. 6, in which the reaction chamber 11 has a flow connection to the discharge chamber 12 of the reactor chamber 5. The filter condensate 3 collected in the receiving area 15 of the shaft 10 can leave the reaction chamber 11 via the gap created between the shaft 10 and the bushing 16 and finally - as in Fig. 7 - in the direction of the collecting chamber connection 8, which establishes the connection to the collecting chamber 9 when the valves 34 and 35 are open.

[0101] The receiving area 15 can then be cleaned, if necessary, preferably by blowing inert gas into the reactor chamber 5. The bearings of the shaft 10 can also be cleaned in this way within the reactor chamber 5.

[0102] The Fig. 8 to 12 disclose a further of several other possible embodiments of a reactor device 1. As initially described with reference to Fig. As can be seen from Figure 8, the reactor device 1 in this embodiment also has a reactor chamber 5 with a shaft 10, which can separate a reaction chamber 11 from a discharge chamber 12. Between a circumferential portion 13 of the shaft 10 and the reactor housing 4, a bushing 16 is arranged, which is pressed onto the circumferential surface 14 of the shaft 10 by the restoring force of a spring element 39.

[0103] In contrast to the previously described embodiment ( Fig. 4 to 7), the shaft 10 in the second embodiment does not have a receiving area 15 designed as a recess for the filter condensate 3, but instead a curvature 21, which - as for example from Fig. 8 - continues in the direction of the longitudinal extension of the rotational axis 18 of the shaft 10. As a result, the curved circumferential portion 13 of the shaft 10 adjoins the annular end face of the cylindrical bushing 16 not only in the direction of the circumferential curvature of the shaft 10, but also transversely thereto. Thus, an overall annular receiving area 15 is formed around the curvature 21 of the shaft 10, which serves to receive the filter condensate 3.

[0104] The shaft 10 has, in combination with the curvature 21, a through-bore 20 which runs, for example, orthogonally to the rotational axis 18 of the shaft 10, ie in the direction of rotation of the shaft 10, through the shaft 10. The through-bore 20 is spatially separated from the curvature 21 or from two opposite curvatures 21 with respect to the circumferential surface 14 of the shaft 10. In particular, the design is such as, for example, Fig. 8 that the through-bore 20 has a longitudinal direction which is orthogonal to the axis of rotation 18 of the shaft 10, wherein the through-bore 20 opens on the circumferential surface 14 of the shaft 10 centrally between two opposite circumferential partial regions 13.

[0105] According to this embodiment, the emptying of the receiving area 15 located on the circumferential surface 14 of the shaft 10 is carried out in such a way that the shaft 10 rotates about the rotation axis 18, whereby a front end area of ​​the through-bore 20 is pushed into a front opening of the bushing 16 and thus also into the reaction chamber 11. As a result, the filter condensate 3 located in the receiving area 15 can pass through the through-bore 20 from the reaction chamber 11 into the discharge chamber 12. This is shown in the Fig. 10 and Fig. 11 shown.

[0106] As previously with regard to the embodiment of the Fig. 4 to 7, the connections 26 for introducing oxidizing agent into the bushing 16 or the reaction chamber 11 are oriented obliquely to the longitudinal axis 17 of the bushing 16, so that the oxidizing agent flow is directed in the direction of the curvature 21 and an air flow can form in the annular circumferential region of the curvature 21, which air flow swirls the filter condensate 3 together with the oxidizing agent in a spiral manner within the reaction chamber 11 and the connected extension chamber 23.

[0107] As shown, the expansion chamber 23 is preferably tubular. It represents a dead space, i.e., it can only be flowed into and out of, but not through. Preferably, in a specific arrangement, as can also be seen from the figures of the drawing, the expansion chamber 23 has a considerable height. It is preferably arranged vertically along its longitudinal extent, which is a multiple of a corresponding transverse extent (relative to the interior space). Filter condensate 3 stirred up during a reaction can spread along the longitudinal extent in the expansion chamber 23 and then, particularly if no further oxidizing agent is subsequently supplied, collect again by sinking at the reactor bottom 40. Further preferably, the expansion chamber 23 has a diameter perpendicular to its longitudinal extent, or a largest dimension added thereto, which is larger than the dimension of the reactor bottom 40 in the same direction.Preferably, the dimension is approximately two to three times, more preferably five times or less, as large. During the fluidization process, access to the reactor is closed, as is known. Together with the expansion chamber 23, this creates a closed space in which the passivation takes place. Furthermore, the expansion chamber 23 can be arranged and provided with an extension such that the fluidized filter condensate 3 flows vertically past the filter device connection 6 during the fluidization process.

[0108] As is particularly evident from Fig. As can be seen in Figure 12, passivation can also be initiated as a reaction or the start of passivation can be supported by generating a spark. The spark can be Fig. 12, in the expansion chamber 23, but it can also be generated near the actual reactor chamber.

[0109] As from Fig.12, in one possible embodiment, two ignition electrodes 41, 42 are provided, which in the exemplary embodiment are also preferably attached to the end 38 of the extension chamber 23, i.e. close to a tube end of the extension chamber 23, which is preferably tubular in this respect.

[0110] Alternatively, a conventional spark plug or a piezo spark generator can be used. List of reference symbols 1 reactor facility 2 filter device 3 Filter condensate 4 reactor casings 5 Reactor room 6 Filter device connection 7 Portioning device 8 Collection chamber connection 9 Collection chamber 10 Wave 11 Reaction chamber 12 Discharge chamber 13 Circumferential sub-area 14 Circumferential surface 15 Recording area 16 socket 17 Longitudinal axis 18 Rotation axis 19 Recess 20 through holes 21 Curvature 22 Marginal area 23 Extension Chamber 24 Temperature sensor 25 pressure sensor 26 connection 27 Cell wheel housing 28 Cell wheel 29 Front side 30 slices 31 Cell wheel chamber 32 valve 33 Valve 34 Valve 35 Valve 36 spring element 37 Rotation axis 38 Conclusion 39 spring element 40 reactor floor 41 ignition electrodes 42 ignition electrodes QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2021 116 264 A [0005, 0077] WO 2022 / 268497 A1 [0005, 0077] DE 10 2017 206 792 A1

[0007] DE 20 2012 013 036 U1

[0007] DE 10 2019 132 349 A1

[0076] US 2022 / 0362691 A1

[0076]

Claims

[1] Reactor device (1) for carrying out a chemical reaction between a filter condensate (3) and an oxidizing agent to reduce a chemical reactivity of the filter condensate (3) in the context of at least one passivation process, wherein the reactor device (1) has a reactor chamber (5) surrounded by a reactor housing (4) with a filter device connection (6) for establishing a fluidic connection between the reactor device (1) and a filter device (2) and a collection chamber connection (8) for establishing a fluidic connection between the reactor device (1) and a collection chamber (9) for receiving passivated filter condensate (3), wherein the reactor chamber (5) is further divided by a reactor base (40) into a reaction chamber (11) and a discharge chamber (12), characterized byin that the reactor base (40) is designed to be displaceable between a first and a second operating position, wherein the reactor base (40) forms part of the reaction chamber (11) in the first operating position and part of the discharge chamber (12) in the second operating position, and the subdivision can be removed during the displacement of the reactor base (40). [2] Reactor device according to claim 1, characterized by that the reaction chamber (11) has the filter device connection (6) and that the discharge chamber (12) has the collection chamber connection (8). [3] Reactor device (1) according to claim 1 or 2, characterized by that the reactor base (40) has at least one receiving area (15) for the filter condensate (3). [4] Reactor device (1) according to one of the preceding claims, characterized bythat the reactor base (40) is part of a shaft (10) arranged in the reactor chamber (5), in particular mounted on the reactor housing (4), and rotatable relative to the reactor housing (4). [5] Reactor device (1) according to claim 4, characterized by that the reaction chamber part (11) has a bushing (16) which is pressed, in particular by means of spring force, onto a peripheral portion (13) of the shaft (10) comprising the reactor base (4), which bushing connects the shaft (10) to the reactor housing (4), wherein more preferably the shaft (10) is rotatable between a passage position and a shut-off position while maintaining contact with the bushing (16) [6] Reactor device (1) according to claim 5, characterized by that a longitudinal axis (17) of the bushing (16) is oriented orthogonally to a rotation axis (18) of the shaft (10). [7] Reactor device (1) according to one of claims 3 to 6, characterized bythat the receiving area (15) has a recess (19), in particular a concave depression. [8] Reactor device (1) according to one of claims 3 to 6, characterized by that the receiving area (15) has a through-bore (20) running transversely to the axis of rotation (18) and a curvature (21) formed on the at least one circumferential partial area (13) of the shaft (10) and running transversely to a circumferential direction of the shaft (10), in particular a convex elevation protruding in the radial direction relative to an end-side edge area (22) of the circumferential surface (14) of the shaft (10). [9] Reactor device (1) according to one of the preceding claims, characterized byin that the reactor housing (4) has a particularly tubular expansion chamber (23) into which the filter condensate (3) can be introduced against the force of gravity to assist passivation, wherein the expansion chamber (23) is designed as a dead space into which the filter condensate (3) can be introduced only for passivation, flowing past the filter device connection (6) at a higher level. [10] Reactor device (1) according to one of the preceding claims, characterized byin that the reaction chamber (11) and / or the extension chamber (23) and / or the bushing (16) has at least one temperature sensor (24) and / or at least one pressure sensor (25) and / or at least one connection (26) for introducing gas into the reaction chamber (11), wherein in particular a connection (26) for introducing gas is oriented relative to the receiving area (15), preferably inclined relative to the reactor base (40), in such a way that filter condensate (3) located in the receiving area (15) is swirled within the reaction chamber (11) and / or within the extension chamber (23). [11] Reactor device (1) according to one of the preceding claims, characterized bya portioning device (7) connected to the filter device connection (6) of the reactor device (1), which is designed to separate a first partial amount of a total amount of filter condensate (3) from at least a second partial amount of the total amount of filter condensate (3) and to transfer it into the reaction chamber (11) of the reactor device (1), wherein the portioning device (7) is in particular a lock delimited by valves or a cell wheel lock, and wherein the portioning device (7) preferably has a cell wheel housing (27) and a cell wheel (28) which is closed at least on one end face (29) by a disk (30) axially loaded with a spring force. [12] Reactor device (1) for carrying out a chemical reaction between a filter condensate (3) and an oxidizing agent to reduce a chemical reactivity of the filter condensate (3) in the context of at least one passivation process, wherein the reactor device (1) has a reactor chamber (5) surrounded by a reactor housing (4) with a filter device connection (6) for establishing a fluidic connection between the reactor device (1) and a filter device (2) and a collecting chamber connection (8) for establishing a fluidic connection between the reactor device (1) and a collecting chamber (9) for receiving passivated filter condensate (3), characterized bythat the reactor chamber (5) has a rotatable shaft (10) and a bushing (16) which is pressed with an end region onto a circumferential part region (13) of the shaft (10), which bushing connects the shaft (10) to the reactor housing (4) to form a reaction chamber (11) which is spatially separated from a discharge chamber (12) of the reactor chamber (5). [13] Reactor device (1) according to claim 12, characterized by in that the rotatable shaft (10) is designed to be rotatable between a first and a second operating position, wherein the circumferential portion (13) of the shaft (10) forms part of the reaction chamber (11) in the first operating position and part of the discharge chamber (12) in the second operating position, wherein the separation between the reaction chamber (11) and the discharge chamber (12) can be eliminated during rotation of the shaft (10). [14] Filter device for filtering out particles from a raw gas stream, comprising a filter device (2) having one or more filter elements on which filter condensate (3) collects during filtering, and a reactor device (1) for carrying out a chemical reaction between the filter condensate (3) and an oxidizing agent to reduce a chemical reactivity of the filter condensate (3) in the context of at least one passivation process, wherein the reactor device (1) has a reactor chamber (5) surrounded by a reactor housing (4) with a filter device connection (6) for establishing a fluidic connection between the reactor device (1) and the filter device (2) and a collecting chamber connection (8) for establishing a fluidic connection between the reactor device (1) and a collecting chamber (9) for receiving passivated filter condensate (3),wherein the reactor device (1) is further arranged below the filter device (2) in order to enable transport of the filter condensate (3) from the filter device (2) into the reactor device (1) also using gravity, wherein the reactor device (1) has an extension chamber (23) into which the filter condensate (3) can be brought against gravity to assist passivation, , characterized by that the filter device connection (6) and the collection chamber connection (8) can be closed to carry out the passivation process, and that the extension chamber (23) is designed as a dead space into which the filter condensate (3) can be brought, flowing past the filter device connection (6) at a height, only for passivation. [15] Method for passivating filter condensate (3) in a reactor device (1) having a reactor chamber (5), wherein the reactor chamber (5) can be closed in a gas-tight manner and the passivation in the reactor chamber (5) is carried out with a time-limited supply of oxidizing agent in a first passivation process, characterized by that the passivation is repeated in a second passivation process or in further passivation processes in accordance with a pressure reached in the reactor chamber (5) in the first passivation process or a temperature reached in the reactor chamber (5) in the first passivation process. [16] Method according to claim 15, characterized by that the supply of oxidizing agent is used to stir up the filter condensate (3). [17] Method according to claim 15 or 16, characterized bythat the second or further passivation process is carried out after the filter condensate (3) has collected again on a reactor floor (40) of the reactor chamber (5). [18] Method according to one of claims 15 to 17, characterized by the procedural steps: Filling filter condensate (3) into a reaction chamber (11) of the reactor space (5); Introducing oxidizing agent into the reaction chamber (11); Mixing the filter condensate (3) with the oxidizing agent to reduce the chemical reactivity of the filter condensate (3); Moving a reactor base (40) dividing the reactor space (5) into the reaction chamber (11) and a discharge chamber (12) from a first operating position, in which the reactor base (40) forms part of the reaction chamber (11), into a second operating position, in which the reactor base (40) forms part of the discharge chamber (12), the subdivision being removed during the movement of the reactor base (40); Emptying the filter condensate (3) located in the reaction chamber (11) into the discharge chamber (12) and / or into a collection chamber (9) connected to the discharge chamber (12). [19] Reactor device (1), filter device or method for operating a reactor device (1), characterized by one or more of the characterizing features of any of the preceding claims.

Images