DEVICE FOR REMOVING ORGANIC COMPONENTS OF COOKING FUMES FROM AN EXHAUST AIR FLOW

Description

[0001] The invention relates to a device for removing organic components of cooking fumes from an exhaust air stream, comprising a housing with at least one inlet opening and at least one outlet opening for the exhaust air stream, at least one regenerable filter arranged in a filter chamber of the housing in the exhaust air stream for storing organic components from the exhaust air stream in a control operating mode, at least one fan which can be activated in a regeneration operating mode for generating a regeneration air stream which releases the stored organic components from the filter, at least one catalyst arranged in the regeneration air stream for splitting the organic components released from the filter, and at least one closure device for closing the inlet opening and / or the outlet opening in the regeneration operating mode.

[0002] Such a device is disclosed in EP 2 893 967 A1 and is already available on the market under the name "berbel recirculation filter permalyt ®< BUR 150." This device is particularly suitable for extractor hoods operating in recirculation mode. A disadvantage of the known solution is the installation space required for the device, as the catalyst in the filter chamber requires sufficient distance from the filter, so the filter chamber must be very large. This makes the previously known device unsuitable for installation under the kitchen countertop, especially with a cooktop extractor where the exhaust air is drawn downwards ("downdraft").

[0003] US 6 358 374 B1 also discloses a device mentioned above, wherein the catalyst is arranged in a catalyst chamber of the housing that is separate from the filter chamber, wherein regeneration air connections are provided between the filter chamber and the catalyst chamber, through which the regeneration air flow circulates over the catalyst and the filter in the regeneration operating mode.

[0004] It is therefore an object of the invention to provide an improved device which requires less installation space and in particular enables installation under the worktop in the case of a cooktop extractor.

[0005] This object is achieved by a device having the features of claim 1.

[0006] The invention provides a regeneration air duct in the catalyst chamber, which guides a portion of the regeneration air flow laterally past the catalyst to cool the catalyst on its outer surface. Active cooling of the catalyst on its outer surface allows for a smaller installation space for the catalyst chamber, since smaller distances between the catalyst chamber walls and the cooled surface of the catalyst are sufficient. The catalyst chamber, which is separate from the filter chamber, can be designed smaller than the installation space saved by separating the filter and catalyst in the filter chamber, so that the device as a whole can be constructed more compactly while maintaining the same filter performance.The arrangement of the catalyst in the catalyst chamber separate from the filter chamber enables sufficient shielding in the control mode, since the catalyst chamber is only connected to the filter chamber via the regeneration air connections, via which the regeneration air flow circulates between the filter chamber and the catalyst chamber via the catalyst and the filter in the regeneration mode.

[0007] Advantageous embodiments and further developments of the invention emerge from the dependent claims. It should be noted that the features listed individually in the claims can also be combined with one another in any technologically expedient manner, thus revealing further embodiments of the invention.

[0008] According to an advantageous embodiment of the invention, the catalyst chamber is connected to the filter chamber via a regeneration air inlet connection and a regeneration air outlet connection, located upstream and downstream of the filter, respectively, in the flow direction of the exhaust air flow, for circulating the regeneration air flow over the catalyst and the filter. The flow direction of the regeneration air flow is reversed from the flow direction of the exhaust air flow through the filter. By reversing the flow direction of the regeneration air flow relative to the exhaust air flow in the filter, embedded organic components can be released from the filter particularly easily.Through the regeneration air inlet connection arranged in the flow direction of the exhaust air flow upstream of the filter in the filter chamber, the regeneration air flow generated during regeneration operation can be directed from the filter in the filter chamber into the catalyst chamber, where the organic components released from the filter are broken down by the catalyst before the air heated by the catalyst re-enters the filter chamber through the regeneration air outlet connection in the flow direction of the exhaust air flow behind the filter.

[0009] Particularly preferred is an embodiment which provides for at least two regenerable filters for storing organic constituents from the exhaust air stream, each in a separate filter chamber of the housing. By arranging two filters in separate filter chambers, the filtering performance of the device can be increased without losing the advantages of a compact design. Furthermore, one filter in one filter chamber can be regenerated in regeneration mode, while another filter in another filter chamber continues to store organic constituents from the exhaust air stream in normal operating mode. For this purpose, the regeneration air connections of the filter chamber remaining in normal operating mode are preferably closed by flaps.

[0010] A particularly advantageous embodiment of the invention relates to each filter chamber having its own inlet opening and at least one outlet opening for the exhaust air flow, as well as a closure device for closing the inlet opening and / or the outlet opening in the regeneration operating mode. By closing the inlet opening and / or the outlet opening, the filter chamber can be encapsulated for the regeneration mode, so that the regeneration air flow can easily circulate between the catalyst chamber and the filter chamber via the catalyst and the filter. Closing the inlet opening and outlet opening enables effective heating of the filter in the filter chamber by the regeneration air flow circulating between the filter chamber and the catalyst in the catalyst chamber during regeneration operation. This allows the stored organic components to be released from the filter particularly effectively.

[0011] A particularly advantageous embodiment of the invention provides that each filter chamber is connected to the catalyst chamber via its own regeneration air connections. By connecting the filter chambers via their own regeneration air connections, the catalyst in the catalyst chamber can regenerate multiple filters, thus enabling further optimization of the installation space used for the device. The separate arrangement of the catalyst in the catalyst chamber enables its use for the separation of organic components from multiple filters arranged in different filter chambers. Thus, the organic components of the exhaust air stream released from the filters in the different filter chambers can be separated in the same catalyst, which requires only one catalyst chamber in the device, thus enabling optimized use of the installation space required for the device.

[0012] An advantageous embodiment of the invention provides that each filter chamber is assigned its own fan, wherein the regeneration air flow generated by the assigned fan circulates over the catalyst against the flow direction of the exhaust air flow through the filter in the filter chamber. With its own fan, a regeneration air flow can be easily generated separately for each filter chamber, so that the filters in the filter chambers can be operated independently of one another, but also jointly in control mode, where organic components from the exhaust air flow are stored in the filter, or in regeneration mode, where the stored organic components are released from the filter. To switch to regeneration mode, the assigned fan must be activated in order to generate a regeneration air flow over the catalyst in the respective filter chamber.

[0013] A particularly advantageous embodiment provides that the circulating regeneration air flow is heated by the catalyst in regeneration mode and flows through the filter in the opposite direction to the flow direction of the exhaust air flow in normal mode, dissolving components embedded therein, which are then broken down in the catalyst. This allows the energy required by the catalyst to dissolving the organic components released from the filter to be used to dissolve the stored organic components from the filter. The heat energy generated by the catalyst is thus not wasted by the circulating regeneration air flow in regeneration mode.

[0014] Further features, details, and advantages of the invention will become apparent from the following description and the drawings, which show an exemplary embodiment of the invention. Corresponding objects or elements are provided with the same reference numerals in all figures. They show: Figure 1 device according to the invention, Figure 2 opened device in control operating mode, Figure 3 opened device in regeneration operating mode from the front, Figure 4 detailed view of catalyst chamber, Figure 5 opened device in regeneration operating mode from the rear, and Figure 6 detailed view of catalyst.

[0015] In the Figure 1Denoted by the reference numeral 1, a device according to the invention is shown. The device 1 serves to remove organic components of cooking vapors from an exhaust air stream 2, which can enter the housing 3 of the device 1 via two inlet openings 4 and exit the housing 3 again via two outlet openings 5. The exhaust air stream 2, indicated here by block arrows, can be generated by one or more fans (not shown) which, arranged upstream of the inlet openings 4, blow the exhaust air stream 2 into the housing 3 or arranged downstream behind the outlet opening 5, suck the exhaust air stream 2 out of the housing 3. The housing 3 of the device 1 shown here is deliberately designed to be very flat in order to be able to be installed in a space-saving manner in a kitchen cupboard (at the rear, on the rear wall) below the worktop. This makes the device 1 particularly suitable for use in the recirculation mode of a cooktop extractor.Alternatively, the housing 3 of the device 1 can also be installed in the base of a kitchen cabinet (under the cabinet floor).

[0016] For further explanation, the housing 3 of the device according to Figure 1 in the Figure 2shown open, so that the view into the filter chambers 6, 7 in the housing 3 is clear. In the filter chambers 6, 7, regenerable filters 8 are each provided for storing organic components from the exhaust air stream 2. Each filter chamber 6, 7 has its own inlet opening 4 and at least one separate outlet opening 5 for the exhaust air stream 2. The air from the exhaust air stream 2 flows through the diagonally inserted filter mats of the filters 8 from top to bottom. The housing 3 shown here has a total of two filter chambers 6, 7, but more filter chambers or filters 8 are also conceivable. However, designs with only one filter in a single filter chamber are also possible. In the filter chambers 6, 7, regenerable filters 8 are each arranged for storing organic components from the exhaust air stream 2. In normal operating mode, the filters 8 filter the exhaust air stream 2 flowing from the inlet opening 4 to the outlet opening 5 through the filter chamber 8.This allows unpleasant odors from cooking fumes to be captured in filter 8, allowing the exhaust air stream 2 to be released into the room air free of these odors in recirculation mode. During cooking, the exhaust air stream 2 is passed through the activated carbon mats of filter 8, where the odor-causing organic components are filtered out of the exhaust air and stored in filter 8.

[0017] In the Figure 3 the device 1 is according to Figure 2not shown in regular operating mode, but in a regeneration operating mode. The regeneration operating mode preferably starts automatically after the cooking process. In the regeneration operating mode, activated fans 9 generate a regeneration air flow 10 that releases the stored organic components from the filter 8. In the exemplary embodiment shown here, each filter chamber 6, 7 is assigned its own fan 9, with the regeneration air flow 10 generated by the assigned fan 9 flowing over a catalyst 11, which serves to break down the organic components released from the filter 8. The cooking odors, i.e. the organic components from the exhaust air flow 2, are broken down into water and carbon dioxide in the catalyst 11 by a thermocatalytic process.To reduce noise, the connection of the fans 9 to the housing 3 is preferably made of dampening rubber, which significantly reduces fan noise. The catalyst 11 is arranged in a catalyst chamber 13 of the housing 3, separate from the filter chambers 6, 7. The separation of the catalyst 11 in the catalyst chamber 13 enables a particularly compact device 1. Regeneration air connections 14, 15 are provided in the housing 3 between the filter chambers 6, 7 and the catalyst chamber 13. Through these regeneration air connections 14, 15, the regeneration air flow 10 circulates in the regeneration operating mode via the catalyst 11 and the filters 8 in the filter chambers 6, 7. The regeneration air flow 10 circulates in the regeneration operating mode against the flow direction of the exhaust air flow 2, here from bottom to top, through the filter 8 in the filter chamber 6, 7, as shown by the block arrows in . Figure 3can be seen. The catalyst chamber 13 has regeneration air inlet connections 14 in the flow direction of the exhaust air flow 2 upstream of the filters 8 in the filter chambers 6, 7 and regeneration air outlet connections 15 in the flow direction downstream of the filters 8 in the filter chambers 6, 7. Each filter chamber 6, 7 thus has its own regeneration air connections 14, 15, via which the filter chambers 6, 7 are connected to the catalyst chamber 13. As a result, the catalyst chamber 13 is connected to the filter chambers 6, 7 via the catalyst 11 and the filters 8 for the circulation of the regeneration air flow 10. For the regeneration operating mode, the inlet openings 4 and preferably also the outlet openings 5 ​​can each be closed via a closure device 12. During the cooking process, the closure flaps of the closure device 12 are preferably opened mechanically by the exhaust air flow.The closure flaps of the closure device 12 are advantageously only opened by the air flow 2 of the cooktop extractor; after the cooktop extractor is switched off, the flaps are closed again by small springs. The closure devices 12 each consist of two aluminum flap parts, a rotary axis, and a leg spring. When the cooktop extractor or the cooktop extractor fan is switched on, the flaps are tensioned against the spring force so that they close again when the fan is switched off. The flow direction of the regeneration air flow 10 in the regeneration operating mode is reversed compared to the flow direction of the exhaust air flow 2 in the normal operating mode through the filters 8. In the regeneration operating mode, the circulating regeneration air flow 10 is heated via the catalyst 11 and directed past an air guide element 17 (. Fig. 4) is divided between the two filter chambers 6, 7 and flows through the filter 8 against the flow direction of the exhaust air flow 2 in the control mode, whereby components stored therein are released, which are then split up in the catalyst 11. In Figure 3The additional housing 18, in which the control electronics of the device 1 are arranged, is also clearly visible. The additional housing 18 also has an interface for connecting a cooktop extractor to the control electronics. When a fan speed is switched on, a contact is closed in the cooktop extractor, which enables a current flow. Based on this current flow, the control electronics of the device 1 then measures the operating hours of the cooktop extractor in order to automatically activate the regeneration mode on a regular basis. The regeneration of the filters 8 preferably starts automatically, either after a continuous cooking time of, for example, 30 minutes or after, for example, 60 minutes of total cooking time. In regeneration mode, the catalyst 11 is heated to approximately 150 - 200°C, preferably approximately 150 - 160°C. This temperature is monitored over the entire regeneration phase of approximately 120 minutes by a temperature sensor 19 ( Fig. 6) and regulated by the control electronics. If the temperature sensor 19 ( Fig. 6 ) or the control system is defective and the temperature of approx. 215°C or approx. 175°C, i.e. approx. 15°C above the intended temperature, is exceeded, the power supply is cut off by a fuse 20 ( Fig. 6 ) and the device 1 cools down. Furthermore, a 230 V mains connection for supplying power to the device 1 is provided in the additional housing 18.

[0018] The Figure 4 shows an enlarged detailed view of the catalyst chamber 13 according to Figure 3. In this view, it can be seen more clearly that a regeneration air duct 16 is provided in the catalyst chamber 13, which guides a portion of the regeneration air flow 10 laterally past the catalyst 11 in order to cool the catalyst 11 on its outer surface. This bypass 16 also actively cools surrounding sheet metal parts. By means of the regeneration air duct 16, the temperature of the surrounding housing parts can be reduced from approximately 100°C to approximately 60°C. By actively cooling the catalyst 11 on its outer surface, the installation space of the catalyst chamber 13 can be reduced, since the active cooling suffices to require smaller distances to the catalyst chamber walls, and additional insulation is unnecessary.

[0019] In Figure 5 the opened device 1 is according to Figure 3also in regeneration mode, but shown from the rear. The block arrows indicate the regeneration air flow 10, which flows through the filters 8 in the filter chambers 6, 7 and dissolves embedded organic components from the filter material and transports them via the fans 9 into the catalyst chamber 13. For this purpose, the regeneration air flow 10 flows via the regeneration air inlet connections 14 into the catalyst chamber 13, where the dissolved organic components from the regeneration air flow 10 are broken down in the catalyst 11. The air of the regeneration air flow 10 is sucked into the catalyst chamber 13 by the fans 9 and blown out through the hot catalyst 11 downwards below the filters 8 back into the filter chambers 6, 7, so that the hot air (approx. 50-60 °C) heats the filter mats of the filters 8.When the filter mats are heated, the embedded odorous substances are released and forced through the catalyst 11 by the fans 9. In the catalyst 11, the odorous substances are broken down into H 2 O and CO 2 by the high temperature (approximately 150-160 °C) and by a precious metal coating or a precious metal-free mixed metal oxide coating or a palladium surface of the catalyst. This regeneration of the filters 8 can be repeated almost indefinitely.

[0020] The Figure 6 shows an enlarged detailed view of the catalyst 11 according to Figure 5 . In this detailed view, it can be seen that the temperature sensor 19, via which the control electronics controls the catalytic converter 11, is provided on the outer surface of the catalytic converter 11. Furthermore, a fuse 20 is provided, which enables a safety shutdown of the heating cartridge of the catalytic converter 11. List of reference symbols

[0021] 1Device 2Exhaust air flow 3Housing 4Inlet opening 5Outlet opening 6First filter chamber 7Second filter chamber 8Filter 9Fan 10Regeneration air flow 11Catalyst 12Closing device 13Catalyst chamber 14Regeneration air inlet connection 15Regeneration air outlet connection 16Regeneration air duct 17Air guide element 18Additional housing 19Temperature sensor 20Fuse

Claims

1. A device (1) for removing organic components from cooking vapours from a waste air stream (2), said device comprising - a housing (3) with at least one inlet opening (4) and at least one outlet opening (5) for the waste air stream (2), - at least one regenerable filter (8), which is arranged in a filter chamber (6, 7) of the housing (3) in the waste air stream (2), for trapping organic components from the waste air stream (2) in a control operating mode, - at least one fan (9), which is activatable in a regeneration operating mode, for generating a regeneration air stream (10) releasing the trapped organic components from the filter (8), - at least one catalyst (11), which is arranged in the regeneration air stream (10), for breaking down the organic components released from the filter (8), and - at least one closure means (12) for closing the inlet opening (4) and / or the outlet opening (5) in the regeneration operating mode, wherein the catalyst (11) is arranged in a catalyst chamber (13) of the housing (3) separate from the filter chamber (6, 7), wherein regeneration air connections (14, 15) are provided between the filter chamber (6, 7) and the catalyst chamber (13), through which connections the regeneration air stream (10) circulates via the catalyst (11) and the filter (8) in the regeneration operating mode, characterised by a regeneration air guide (16) in the catalyst chamber (13), which guides a part of the regeneration air stream (10) laterally past the catalyst (11) in order to cool the catalyst (11) on its outer surface.

2. The device according to claim 1, characterised in that the catalyst chamber (13) is connected via a regeneration air intake connection (14) and a regeneration air discharge connection (15) before and after the filter (8), respectively, in the flow direction of the waste air stream (2) for circulation of the regeneration air stream (10) via the catalyst (11) and the filter (8), wherein the flow direction of the regeneration air stream (10) is reversed in relation to the flow direction of the waste air stream (2) through the filter (8).

3. The device (1) according to claim 1 or 2, characterised in that at least two regenerable filters (8) for trapping organic components from the waste air stream (2) are provided, in each case in a dedicated filter chamber (6, 7) of the housing (3).

4. The device (1) according to claim 3, characterised in that each filter chamber (6, 7) has a dedicated inlet opening (4) and at least one dedicated outlet opening (5) for the waste air stream (2) and a closure means (12) for closing the inlet opening (4) and / or the outlet opening (5) in the regeneration operating mode.

5. The device (1) according to claim 4, characterised in that each filter chamber (6, 7) is connected via dedicated regeneration air connections (14, 15) to the catalyst chamber (13).

6. The device (1) according to any one of claims 3 to 5, characterised in that each filter chamber (6, 7) is assigned a dedicated fan (9), wherein the regeneration air stream (10) generated in each case by the assigned fan (9) circulates through the filter (8) in the filter chamber (6, 7) via the catalyst (11) against the flow direction of the waste air stream (2).

7. The device (1) according to any one of the preceding claims, characterised in that the circulating regeneration air stream (10) is heated in the regeneration operating mode via the catalyst (11) and flows through the filter (8) against the flow direction of the waste air stream (2) in the control operating mode, and releases components trapped therein, which are then broken down in the catalyst (11).