Suction of kitchen exhaust air according to requirements and energy efficiency

Abstract

The present invention relates to methods and devices for rapidly increasing the throughput of an extraction device, in particular for the energy-efficient and demand-based extraction of kitchen exhaust air, which comprises at least the following components: - extraction hood 110 - advantageously a centrifugal grease pre-separator - a fan 140, which is provided with a speed control for a variable extraction air volume and which can therefore increase the extraction volume from a low partial load operation particularly quickly, i.e. preferably by a factor of at least two, more preferably by a factor of at least five and most preferably by a factor of at least eight, wherein at least one of the following measures is used for the rapid increase of the extraction volume: - increasing the speed of the fan 140 by using a flywheel 146, which is preferably designed as a flywheel or a technically equivalent design,which ideally allows the (mechanical) energy stored in the flywheel or the technically equivalent design to be transferred quickly to the fan via a coupling 144 - introduction of jet-pulse compressed air 120 - activation of a separate peak load fan 162, which is advantageously integrated into the extraction system via at least one control damper 166 - activation of a vacuum reservoir 168, which is preferably kept at a negative pressure for a long term or permanently by means of an evacuation blower 170 and which can advantageously be integrated into the extraction system via at least one valve or damper 172.

Description

[0001] The invention primarily aims to increase energy efficiency, especially in the area of ​​kitchen exhaust air extraction, preferably in commercial kitchens.

[0002] In commercial kitchens with multiple cooking stations, exhaust air is often extracted at maximum volume throughout operation. The extracted air is then replaced by naturally flowing fresh air. This is particularly noticeable during the heating season when the incoming cold air must be heated separately. The demand-based extraction system proposed by the invention preferably captures only the cooking stations currently in use and optimizes the fan speed and / or the extraction volume to capture the constantly changing total volume of kitchen exhaust air, or the constantly changing total volume actually required, while minimizing or ideally eliminating excess extraction. In addition to saving heating energy, the speed control can also reduce the electricity used to drive the fan.

[0003] A particular challenge in the demand-based extraction of kitchen exhaust air is capturing the surges of steam released when pots and pans are opened. The invention focuses on the rapid and time-limited increase in the extraction air volume to capture these surges. "Rapid" in the context of the present invention means an extraction rate that can be increased sufficiently, at least within the time it takes for a steam cloud to travel from the top of a pot when the lid is removed to the midpoint of the extraction hood, to capture and extract the steam surge completely or almost completely, and in particular to prevent it from escaping downwards from the extraction hood into the room.To achieve this, the invention provides that the extraction power at a single cooking station can be increased from at least 20 percent to 80 percent within two seconds.

[0004] The peripheral components, such as the grease separators that operate on the centrifugal principle, must be adapted to highly fluctuating extraction volumes and flow velocities.

[0005] The invention further proposes heat recovery, preferably via finned heat exchangers operated with an air-to-water (heat transfer fluid) system. The advantage of air-to-water systems over air-to-air heat exchanger systems lies in their smaller dimensions, which are due to the significantly higher heat transfer coefficient on the water side. For further details, reference is made to the relevant sections of the VDI Heat Atlas. When the thermal energy of the exhaust air has been transferred to water or another liquid medium, the recovered heat energy can be distributed via smaller pipe cross-sections compared to warm air distribution systems. This is particularly advantageous in existing buildings, for example, when the heat demand in the form of fresh air preheating, domestic hot water heating, or a potential feed point into a heating system is located some distance from the exhaust air heat exchanger.Optionally, the heat recovered from the exhaust air can be raised in temperature using a heat pump, preferably electrically operated. A temperature increase of approximately 40 to 50 Kelvin is generally targeted to ensure a favorable ratio between electrical energy input and thermal energy output. The so-called COP (coefficient of performance) or seasonal performance factor should be above 3, ideally above 4 to 5, or even higher. Reference is made to publications from heat pump manufacturers, such as Vaillant Deutschland GmbH & Co. KG (air / water heat pump aroTHERM plus, technical data) https: / / www.vaillant.de / heizung / produkte / luft-wasser-warmepumpe-arotherm-plus-194816.html, accessed October 2025) and Buderus AG / Bosch Thermotechnik GmbH (heat pump guide, COP of the heat pump explained simply, https: / / www.buderus.de / de / waermepumpe / cop-wert, accessed: October 2025).

[0006] In Fig. 1 The invention is schematically illustrated in a preferred embodiment by way of example with a cooktop 100, the fumes 102 of which, in particular consisting of water vapor, cooking fat vapor and / or the like, are extracted by means of an extraction hood 110 and an exhaust fan 140. Preferably, a sensor 122, preferably designed as an infrared sensor, is provided above the cooktop and monitors each cooktop from above. This sensor can preferably control a control flap 124 so that the cooktop can be extracted via an open control flap when in operation. When the cooktop is not in operation, the sensor detects this based on the lower temperature and the control flap can be closed so that the amount of air drawn in by the fan is directed to the cooktops in operation, which are shown in the diagram for clarity. Fig. 1 which are not shown separately in pictures, can be concentrated.

[0007] Extraction hoods often incorporate grease separators (here: 112, 114, 116) that remove a large portion of the grease load directly from the gas stream after extraction, thus significantly reducing contamination of the downstream exhaust system. These grease separators operate on the centrifugal principle, in which the extracted gas stream is guided through deflectors. At high gas velocities, the larger grease droplets, due to their inertia, can no longer follow the deflection and are carried by centrifugal force to the deflector walls, where they adhere and are thus separated from the gas stream.

[0008] Different deflection radii are required for different gas velocities, enabling optimal separation. This means that a single centrifugal separator cannot always operate within its optimal range when gas flows fluctuate significantly. Fig. 1 Figure 1 shows an example of a grease separator divided into three adjacent segments (112, 114, 116). At low extraction rates, only grease separator 112 is active. At medium extraction rates, the second grease separator 114 is also activated (see figure 116). Fig. 4 ) and at high extraction volumes, the third grease separator 116 is also activated. With increasing extraction volume, more separator surface area is exposed to the airflow, so that the flow velocity fluctuates in significantly smaller intervals and the centrifugal separation effect is improved. A different configuration of the grease separator than the three-part one described here is also possible and is part of the invention even without explicit mention.

[0009] For clarity, the three segments of the grease separator are shown side by side in an illustration (112, 114, 116).

[0010] In practice, especially in large kitchens, an alternative design may be more practical. The abstract, pictorial representation of Fig. 1 The configuration, in which the low-velocity zone 112 is located in the left part, the switchable medium-velocity zone 114 in the center of the extraction hood, and the high-velocity zone 116 in the right part of the extraction hood, is therefore to be considered a simplified representation. The extraction flow should not be directed in different directions depending on the volume.

[0011] For large grease separator surfaces, a division of the grease separator segments into smaller, adjacent areas may be useful (though this is not shown for clarity). This could be achieved, for example, by dividing each segment into three smaller areas: 112, 114, 116, 112, 114, 116, 112, 114, 116.

[0012] Other embodiments of the grease separator segments are also part of this invention without explicit pictorial or textual mention, provided they serve the same purpose.

[0013] Preferably, the switching on and off of the flexibly deployable grease separators 2 and 3 is based on the pressure difference, particularly preferably on the pressure difference between the inlet and outlet sides of the grease separators, which results from the different flow velocities. Fig. 4 This is achieved, for example, through springs. Grease separation serves to pre-clean the exhaust air.

[0014] The optional exhaust air purification system 130 shown can consist, for example, of filters, potassium permanganate packings, activated carbon, stove furnace coke, electrostatic precipitators, or UV / ozone and plasma units, as well as combinations of the aforementioned and other individual components. This system performs a fine purification of grease and odor particles.

[0015] Furthermore, the individual air currents are in Fig. 1 shown separately, namely the warm exhaust air before exhaust air purification 132, the cold supply air before heat exchanger 2 134, the heated supply air after heat exchanger 2 136, which may optionally contain recirculated air (partially), and the cooled exhaust air after heat exchanger 1 138.

[0016] The following components are provided for heat recovery from the extracted air: 150 Heat exchanger 1, preferably in finned design for heat exchange from air to water or less preferably with other heat transfer fluid, 152 Heat exchanger 2, preferably in finned design for heat exchange from water to air, (less preferably: other heat transfer fluids), advantageously with circulation pump 154 ​​for water / heat fluid circuit, 156 optional heat pump, 158 optional recirculation of air, preferably partial, the volume flow control of the recirculation portion is shown here without detailed illustration, furthermore an optional separate fan 160 can be provided for supplying the supply air.

[0017] When the lid of a cooktop is opened, a phenomenon known as "surge" occurs, in which a large amount of steam or cooking fat rises in a very short time. The amount of extraction air required to capture this brief surge is many times greater than that required for continuous operation of the cooktop, especially with the lid closed. The maximum extraction rate required in this case can be eight to ten times the normal extraction rate with the lid closed. In a kitchen with, for example, 10 cooktops requiring separate extraction, the extraction rate can therefore theoretically fluctuate by a factor of approximately 8 to 10 x 10 = 80 to 100 when considering the two extreme cases: "one cooktop operating with the lid closed" and "all cooktops operating with the lid open." However, these extreme cases rarely, if ever, occur in quick succession.

[0018] The preferred subject matter of the invention is the practically relevant case of reliably capturing the steam surge from typically one lid opening, or at most two to three parallel lid openings in the case of 10 cooking zones, with the extraction system. With regard to a single cooking zone, this means that the extraction rate for that cooking zone must be increased by a factor of approximately eight to ten within preferably less than one second. However, if several cooking zones are operated simultaneously and the base extraction airflow is higher, this factor decreases.

[0019] Nevertheless, the amount of air extracted to capture the surge must be increased faster than a fan under load can normally increase its speed.

[0020] The invention provides the following solutions: a) Preferred solution: rapid speed increase via a flywheel 146, which can be engaged by means of a clutch 144. Due to the stored rotational energy, the flywheel can quickly overcome the comparatively low inertia of the fan 140 and its motor 142, which is preferably speed-controlled by a frequency converter, during normal operation without surges, thus significantly increasing the extraction rate almost instantaneously. During normal operation without surges, the flywheel 146 is maintained at its operating speed by a separate motor 148. A rapid speed increase within the meaning of the present invention results in an increase in extraction performance, preferably at a single cooking zone, from 20 percent to at least 80 percent within a maximum of two seconds.

[0021] To ensure that the increased extraction volume resulting from the increased fan speed can be dissipated as quickly as possible, essentially back towards the exhaust hood, mounting the fan near the hood is beneficial. Smaller duct cross-sections can also promote the rapid propagation of the increased extraction volume due to the higher flow velocities, although this approach is limited by the general limits of typical flow velocities in kitchen exhaust systems, which are typically up to about 5 m / s.

[0022] Optionally, the flywheel can be equipped with a 145 gearbox, allowing its rotational speed to be significantly higher or lower than the maximum speed or the target speed for surge capture of the fan. Many exhaust fans are operated in practice at maximum speeds between 2,000 and 3,000 revolutions per minute. If the gearbox has a 1:5 ratio, for example, the rotational speed of the flywheel can be selected five times higher or lower.

[0023] Other variants that can be used instead of the flywheel described and preferred here, with a technically comparable effect, i.e., a comparably rapid increase in the speed of the fan 140, are also part of the invention even without explicit textual and pictorial description, since they are to be regarded as "quasi-equivalent technical embodiments" and are therefore also considered and referred to as flywheels within the meaning of the invention. Such alternative variants could be, for example, spring (force) accumulators, compressed air and hydraulic motors, or storage devices for potential energy, such as weights on ropes on pulleys, as used, among other things, in old cuckoo clocks driven by wind-up weights.

[0024] A less preferred option b) is the introduction of jet-pulse compressed air 120 (see in particular Fig. 1 (preferably at an angle to the direction of the extraction flow), in which, due to Bernoulli's principle, a negative pressure is created in the vicinity of the rapidly flowing compressed air, and this negative pressure can be used to increase the extraction air volume. This principle of negative pressure generation is used in water jet and steam jet pumps, as well as in the cleaning of industrial bag filter systems with compressed air pulses. For detailed questions, please refer to the relevant technical literature on industrial filters, such as Löffler "Dust Separation", ISBN 3-13-712201-5, or Vauck / Müller "Basic Operations in Chemical Process Engineering", ISBN 3-342-00629-3. Also, for reasons of noise reduction, the application of jet-pulse technology in kitchen areas is considered a less desirable option.

[0025] Another less preferred variant c) of the invention is in Fig. 2 The diagram shows that, in parallel to the speed-controlled fan 140, which is responsible for the base and medium load of the extraction, there is another peak load fan 162 with associated motor 164, which preferably runs continuously at high speed against a closed control damper 166, which is preferably installed on the intake side. When a surge occurs, this damper can be opened quickly so that an additional volume of air is extracted abruptly.

[0026] If this additional extraction volume is to be directed specifically to one of several cooking zones, an additional duct system with a preferably small flow cross-section is advantageous for rapid propagation. This is achieved by means of a [unclear - possibly referring to a specific duct system or system]. Fig. 1 In addition to the main duct shown for the medium and base load of the extraction system, a parallel duct system with its own control valves allows the peak load to be directed precisely to the extraction point. However, the complexity of this parallel system is so high that its practical application appears questionable due to structural and, above all, economic considerations.

[0027] A fourth, less preferred option d) is in Fig. 3 A schematic representation is shown with a cooking station. A vacuum storage container 168 is provided, which can be maintained at negative pressure during normal extraction by means of an evacuation blower 170, and which preferably uses a low-cross-section extraction duct network parallel to the normal extraction system to quickly and for a short period of time bring the negative pressure to the extraction point when a surge is detected. "Quickly" in the sense of the present invention means that the extraction volume can preferably be increased from 20 percent to at least 80 percent at a single cooking station within a maximum of two seconds.

[0028] Preferably, each individual extraction point can be supplied with a peak extraction load via separate valves or flaps 172. However, primarily due to the large dimensions of the vacuum reservoir, which can be approximately in the cubic meter range, and the high strength requirements for vacuum reservoirs, this option is considered less desirable.

[0029] The in Fig. 4 The centrifugal grease separators shown horizontally are normally installed vertically or at a slight angle to the vertical in extractor hoods above cooktops. The flow forces resulting from the deflection of the gas flow primarily separate larger grease droplets on the walls, from where they run down as a liquid film. These centrifugal grease separators serve as a pre-separation mechanism and, in their simple form, correspond to the prior art. The novel aspect of the invention is that the separation is achieved by dividing the flow into different segments, several of which are activated at higher flow velocities and close again at lower flow velocities, so that the flow velocity over the respective active segments remains approximately the same or at least within a similar range.In the prior art, only a single segment is provided in which all areas are subjected to flow regardless of a time-varying flow velocity. In contrast, the invention provides several areas (segments) that can advantageously be switched on or off depending on the flow velocity. This means that the range of flow velocities within the active elements is smaller. "Active" in the context of the present invention means that the elements are subjected to flow from the exhaust air to be cleaned and are not temporarily deactivated at that time, for example, by a spring-loaded flap at low extraction rates.

[0030] In the left part of Fig. 4 Figure 180 shows a single segment of the centrifugal grease separator. This segment consists of parts 182 centrifugal grease separator according to the state of the art, shown here as an example with three parallel channels and deflector plates with separator troughs at the end, as well as position 184 flow control.

[0031] The incoming, highly fatty exhaust air 186 flows into the centrifugal grease separator 182 on the left side and, after the coarse separation of the grease load, exits again on the right side as slightly fatty exhaust air 188.

[0032] The centrifugal grease separator includes at least one deflector plate 190, which may advantageously be equipped with at least one separator channel 192 or optionally with a differently designed separation geometry for grease droplets.

[0033] The trajectory of a larger grease droplet in the gas stream 196, which is separated after the second deflection at the deflector plate or the separator channel, is shown as an example, as is the trajectory of a smaller grease droplet 198, which passes through the grease separator without separation and exits on the right side with the slightly grease-containing exhaust air.

[0034] A control flap 200 is provided which, in the closed position, blocks the gas flow through the grease separator and, in the open position, releases it. Advantageously, the control flap is provided with an opening and closing mechanism, which can preferably be simply a spring (force) 202 with a mounting 204 and is driven by a higher or lower dynamic pressure of a higher or lower volume of air flowing through the separator.

[0035] Other designs of the grease separator are possible, for example, a variant with motorized adjustment of the control flap, which, via a control system using pressure or flow sensors, ensures a largely homogeneous flow velocity through the grease separator. These and other variants are also within the scope of the invention, provided they ensure that the flow velocity through the separator preferably remains approximately constant, or within a range tolerable for flow force separation, even with strongly fluctuating air volumes.

[0036] In the right part of Fig. 4 An example of a grease separator consisting of three segments is shown, where the top segment is permanently open, the middle segment is open with the spring engaged, and the bottom segment is closed. This example represents operation with a medium suction rate. At maximum suction rate, the lower segment would also be opened by the spring due to the higher back pressure.

[0037] Fig. 5 shows two further variants of the invention, each with a fast-acting control flap 126. On the left side is a simplified arrangement for clarity as shown in Fig. 1 shown, with an extraction hood 110 and a control damper 124. The warm exhaust air 132 is treated analogously to Fig. 1 The air is extracted in this way. A fast-acting control valve 126 is provided in parallel with the control valve 124, shown by the dashed arrows.

[0038] The bypass path to the normal extraction system can be opened quickly via the control damper 126, thereby increasing the extraction rate. Advantageously, no change in fan speed is required.

[0039] The right representation of Fig. 5 shows a similar situation, however, the fast-acting control valve 126 is provided instead of the control valve 124 and a bypass can be dispensed with.

[0040] For the sake of clarity, the illustrations in the figures refer to only one cooking station or extractor hood each. In practical operation of commercial kitchens, many such extraction points are combined in parallel circuits and are usually extracted by a fan, optionally subjected to odor treatment, and released into the atmosphere via a central chimney.

[0041] Another, less preferred, variant of the invention provides that the previously described control valve 124, which is fully open during operation and fully closed during non-operation, is a fast-acting control valve 126, which can also preferably assume intermediate positions, such as 30% open or similar intermediate positions.

[0042] This advantageously allows the extraction rate at the cooktop to be regulated, at least to some extent, without reducing the fan's speed. However, since the fan's power consumption remains high in this embodiment of the invention, the energy-saving aspect of the invention can then only be partially realized.

[0043] Within the scope and for the purposes of the present invention, the term "control valve" is used as a collective term for other throttling devices that have a comparable regulating effect on the airflow. This includes completely different designs, such as pinch valves or the like.

[0044] Another, even less preferred, variant of the invention provides for control flaps 126 that open or close quickly and preferably completely, which completely open or close the extraction cross-section, as in Fig. 5 shown as an example on the right-hand side, and / or connected in parallel to a control valve 124 in bypass, as shown in Fig. 5 An example is shown on the left side.

[0045] For the purposes of the present invention, rapidly closing and opening control valves and control elements are understood to mean that the maximum positions fully open and fully closed can be reached in less than three seconds, preferably in one second and most preferably in less than one second.

[0046] With regard to sound insulation and low power consumption, the preferred variant a) with flywheel mass appears to be the advantageous one.

[0047] Combinations of the individual variants or their components are also part of the invention, even if they are not explicitly mentioned in this combination.

[0048] Advantageous embodiments or aspects of the present invention are, in particular, as follows: Aspect 1) Method and / or device for rapidly increasing the throughput of an extraction device, in particular for the energy-efficient and demand-based extraction of kitchen exhaust air, comprising at least the following components: extraction hood 110, advantageously a centrifugal grease pre-separator, a fan 140 which is provided with a speed control for a variable extraction air volume and which can therefore increase the extraction volume from a low partial load operation particularly quickly, i.e. preferably by a factor of at least two, particularly preferably by a factor of at least five and most preferably by a factor of at least eight, wherein at least one of the following methods and / or devices is used for the rapid increase of the extraction volume: increasing the speed of the fan 140 by using a flywheel 146, which is preferably designed as a flywheel or a technically equivalent design,which can ideally transfer the (mechanical) energy stored in the flywheel or the technically equivalent design quickly to the fan via a coupling 144, is provided for. Introduction of jet-pulse compressed air 120. Connection of a separate peak load fan 162, which is advantageously integrated into the extraction system via at least one control damper 166. Connection of a vacuum reservoir 168, which is preferably kept at a negative pressure long-term or permanently by means of an evacuation blower 170 and which can advantageously be integrated into the extraction system via at least one valve or damper 172. Aspect 2) Method and / or device for centrifugal grease pre-separation, preferably according to aspect 1, which can preferably be operated with optimal flow velocity or throughput by switching individual segments on and off via flow control over a wide volume flow range of the extraction system.

[0049] The present invention relates in particular to a method for preferably rapidly increasing the throughput of an extraction device, especially for extracting kitchen exhaust air, preferably an energy-efficient and demand-based extraction of kitchen exhaust air. which comprises at least the following components: an extraction hood (110), an optional centrifugal grease pre-separator, a fan (140) which is provided with a speed control for a variable extraction air volume and which can increase the extraction volume from a low partial load operation, i.e., in particular 20 percent, particularly quickly, i.e., in particular in a maximum of 2 seconds, i.e., preferably by a factor of at least two, particularly preferably by a factor of at least five, and most preferably by a factor of at least eight, wherein, for the rapid increase of the extraction volume, i.e., in particular from 20 percent to at least 80 percent in a maximum of two seconds, at least one of the following measures is used: an increase in the speed of the fan (140) by providing a flywheel (146), which is preferably designed as a flywheel, which rapidly, i.e.,in particular within a maximum of two seconds, by means of a coupling (144) to the fan (140); an introduction of jet·pulse compressed air (120); an activation of a separate peak load fan (162), which is preferably integrated or can be integrated into the extraction system via at least one control damper (166); activation of a vacuum reservoir (168), which is preferably kept at a negative pressure for a long period of time, i.e., in particular for several hours up to a two-shift workday, i.e., 16 hours, or permanently (24 / 7 / 365) by means of an evacuation blower (170), and which is preferably integrated or can be integrated into the extraction system via at least one valve or damper (172).

[0050] A further embodiment of the invention provides that, for centrifugal grease pre-separation, individual segments are switched on and / or off via flow control over a wide volume flow range of the extraction system with an optimal flow velocity, i.e., in particular an interval of flow velocity acceptable for flow force separation, so that the difference between the minimum separation of the mass of grease droplets compared to the maximum separation is preferably less than 50 percent and particularly preferably less than 20 percent.

[0051] The present invention further relates in particular to a device for preferably rapidly increasing the throughput of an extraction device, especially for the extraction of kitchen exhaust air, preferably an energy-efficient and demand-based extraction of kitchen exhaust air, which comprises at least the following components: an extraction hood (110), an optional centrifugal grease pre-separator, a fan (140) which is provided with a speed control for a variable extraction air volume and which can increase the extraction volume from a low partial load operation, i.e., in particular 20 percent, particularly quickly, i.e., in particular in a maximum of 2 seconds, i.e., preferably by a factor of at least two, particularly preferably by a factor of at least five, and most preferably by a factor of at least eight, wherein, for the rapid increase of the extraction volume, i.e., in particular from 20 percent to at least 80 percent in a maximum of two seconds, at least one of the following measures is provided: an increase in the speed of the fan (140) by providing a flywheel (146), which is preferably designed as a flywheel, which rapidly, i.e.,in particular within a maximum of two seconds, by means of a coupling (144) to the fan (140); an introduction of jet·pulse compressed air (120); an activation of a separate peak load fan (162), which is preferably integrated or can be integrated into the extraction system via at least one control damper (166); activation of a vacuum reservoir (168), which is preferably kept at a negative pressure for a long period of time, i.e., in particular for several hours up to a two-shift workday, i.e., 16 hours, or permanently (24 / 7 / 365) by means of an evacuation blower (170), and which is preferably integrated or can be integrated into the extraction system via at least one valve or damper (172).

[0052] A further embodiment of the invention provides that, for centrifugal grease pre-separation, individual segments are switched on and / or off via flow control over a wide volume flow range of the extraction system with an optimal flow velocity, i.e., in particular an interval of flow velocity acceptable for flow force separation, so that the difference between the minimum separation of the mass of grease droplets compared to the maximum separation is preferably less than 50 percent and particularly preferably less than 20 percent.

[0053] The embodiments shown in the figures of the drawing and the embodiments explained in connection with them serve only to illustrate the invention and are not limiting. Bezugszeichen:

[0054] 100 Cooking zone 102 Vapors 110 Extraction hood 112 Grease separator 1 114 Grease separator 2 116 Grease separator 3 120 Introduction of jet-pulse pressurized fragrance 122 Sensor for detecting the activity of the cooking zone, preferably designed as one infrared sensor per cooking zone, particularly preferably directed from above onto the cooking zone 124 Control damper - particularly without special requirements for speed 126 Fast opening and closing control damper, which preferably can also partially open and close 130 Exhaust air purification e.g. filter, potassium permanganate, electrostatic precipitator, UV / ozone / plasma 132 Warm exhaust air before exhaust air purification 134 Cold supply air before heat exchanger 2 136 Heated supply air after heat exchanger 2, optionally with recirculation (component) 138 Cooled exhaust air after heat exchanger 1 140 Exhaust fan 142 Motor exhaust fan, preferably frequency converter-controlled 144 coupling 145 gearbox 146 flywheel, preferably flywheel 148 motor of flywheel 150 heat exchanger 1,Preferably finned design for heat exchange from air to water, less preferred: other heat transfer fluids 152 Heat exchanger 2, preferably finned design for heat exchange from water to air, less preferred: other heat transfer fluids 154 Circulating pump for preferred water circuit, less preferred: other heat transfer fluids 156 Optional heat pump 158 Optional recirculation of air, preferably partial, volume flow control of the recirculation portion shown here without detailed illustration 160 Optional fan for supply air 162 Separate fan for peak load extraction 164 Motor for peak load fan 166 Control damper for peak load fan 168 Vacuum reservoir 170 Evacuation blower 172 Valves or dampers for targeted supply of the negative pressure to individual extraction points 180 A part of the centrifugal grease separator according to the invention for fluctuating volume flows,Shown here is the component with open flow control 182. Centrifugal grease separator according to the state of the art, shown here by way of example with three parallel channels and deflectors with separator channels at the end 184. Flow control 186. Incoming exhaust air with a high grease content 188. Outgoing exhaust air with a low grease content 190. Deflector 192. Separator channel at the end of the deflector 194. Example of the trajectory of a larger grease droplet in the gas stream 196. Example of the separation of the larger grease droplet in the gas stream 198. Example of the trajectory of a smaller grease droplet through the grease separator 200. Control flap shown here in the open position with a solid thick line, the closed position is shown with a dashed thin line 202. Spring for loading the control flap 200, the spring opens from a certain dynamic pressure of the flow 204. Mounting for spring 202.

Claims

1. A method for preferably rapidly increasing the throughput of an extraction device, in particular for extracting kitchen exhaust air, preferably an energy-efficient and demand-based extraction of kitchen exhaust air, comprising at least the following components: - an extraction hood (110), - an optional centrifugal grease pre-separator, - a fan (140) which is provided with a speed control for a variable extraction air volume and which can increase the extraction volume from a low partial load operation (i.e., in particular, 20 percent) particularly rapidly (i.e., in particular, within a maximum of 2 seconds), i.e., preferably by a factor of at least two, particularly preferably by a factor of at least five, and most preferably by a factor of at least eight, wherein, for the rapid increase of the extraction volume (i.e.,in particular from 20 percent to at least 80 percent in a maximum of two seconds) at least one of the following measures is applied: - an increase in the rotational speed of the fan (140) by providing a flywheel (146), preferably designed as a fly disc, which can quickly (i.e., in particular, within a maximum of two seconds) transfer the (mechanical) energy stored in the flywheel to the fan (140) by means of a coupling (144); - an introduction of jet·pulse compressed air (120); - an activation of a separate peak load fan (162), which is preferably integrated or can be integrated into the extraction system via at least one control damper (166); - an activation of a vacuum reservoir (168), which is preferably evacuated by means of an evacuation blower (170) for a long period of time (i.e., in particular, for several hours up to a two-shift workday, i.e.,is kept under negative pressure for 16 hours) or permanently (24 / 7 / 365), and is preferably integrated or can be integrated into the extraction system via at least one valve or flap (172).

2. Method according to claim 1, which is or can be operated for centrifugal grease pre-separation by fluid-technical switching on and / or off of individual segments over a wide volume flow range of the extraction with optimal (i.e. in particular an interval of flow velocity acceptable for the flow force separation, so that the difference between the minimum separation of the mass of grease droplets compared to the maximum separation is preferably less than 50 percent and particularly preferably less than 20 percent) flow velocity or throughput.

3. Device for preferably rapidly increasing the throughput of an extraction device, in particular for extracting kitchen exhaust air, preferably an energy-efficient and demand-based extraction of kitchen exhaust air, comprising at least the following components: - an extraction hood (110), - an optional centrifugal grease pre-separator, - a fan (140) which is provided with a speed control for a variable extraction air volume and which can increase the extraction volume from a low partial load operation (i.e., in particular, 20 percent) particularly rapidly (i.e., in particular, within a maximum of 2 seconds), i.e., preferably by a factor of at least two, particularly preferably by a factor of at least five, and most preferably by a factor of at least eight, wherein, for the rapid increase of the extraction volume (i.e.,in particular from 20 percent to at least 80 percent in a maximum of two seconds) at least one of the following measures is provided: - an increase in the rotational speed of the fan (140) by providing a flywheel (146), preferably designed as a fly disc, which can quickly (i.e., in particular, within a maximum of two seconds) transfer the (mechanical) energy stored in the flywheel to the fan (140) by means of a coupling (144); - an introduction of jet·pulse compressed air (120); - an activation of a separate peak load fan (162), which is preferably integrated or can be integrated into the extraction system via at least one control damper (166); - an activation of a vacuum reservoir (168), which is preferably evacuated by means of an evacuation blower (170) for a long period of time (i.e., in particular, for several hours up to a two-shift workday, i.e.,is kept under negative pressure for 16 hours) or permanently (24 / 7 / 365), and is preferably integrated or can be integrated into the extraction system via at least one valve or flap (172).

4. Device according to claim 3, which is or can be operated for centrifugal grease pre-separation by fluid-technical switching on and / or off of individual segments over a wide volume flow range of the extraction with optimal (i.e. in particular an interval of flow velocity acceptable for the flow force separation, so that the difference between the minimum separation of the mass of grease droplets compared to the maximum separation is preferably less than 50 percent and particularly preferably less than 20 percent) flow velocity or throughput.

Images