DE102022102905A1 - Cooking device with vapor cleaning and method for operating the cooking device - Google Patents

Abstract

The present invention relates to a cooking appliance (1) with a housing and a cooking chamber (2) arranged in the housing and with a duct (3) arranged in the housing for discharging vapors from the cooking chamber (2) into an environment (4) of the Cooking appliance (1), wherein at least one water trap (6) formed by a volume of water is arranged in the channel (3) for cooling the vapor, the vapor being guided through the volume of water or along the volume of water, and wherein in the channel (3) at least one adsorption filter (7) for removing volatile organic compounds from the vapor is arranged, the adsorption filter (7) being arranged in a first position (3.1) of the duct (3) downstream of the water trap (6), so that the vapor exits from the cooking chamber (2) first flows through the water trap (6) and then through the adsorption filter (7). The invention also relates to a method for cleaning the cooking chamber (2) in such a cooking appliance (1).

Description

technical field

The present invention relates to a cooking appliance with a housing and a cooking chamber arranged in the housing and with a channel arranged in the housing for discharging vapors from the cooking chamber into an area surrounding the cooking appliance. The invention also relates to a method for cleaning the cooking space in such a cooking appliance.

Background of the Invention

Cooking appliances such as ovens are known from the prior art, in which vapors are conducted via a duct from a cooking chamber into the surroundings of the cooking appliance and, for example, are cleaned of volatile organic compounds ("Volatile Organic Compounds" -VOC) by means of a catalyst fabric . In concentrations occurring in cooking appliances, such volatile organic compounds are perceived as an odor nuisance and are therefore undesirable in the vicinity of the cooking appliance, such as a kitchen and/or living room. VOCs occur in high concentrations, in particular during pyrolytic cleaning of a cooking appliance, so that known catalyst fabrics cannot clean the vapors sufficiently to avoid odor nuisance in the environment.

For example, ovens with catalytic converters to clean the vapors are off EP 0 831 277 A1 or EP 1 217 306 A2 known.

It is also made of vapor extractors for cooktops, for example DE 10 2008 023 310 A1 , known to use activated charcoal filters for vapor cleaning, but absorb the VOC only at low temperatures. At temperatures occurring, for example, in baking ovens, particularly during pyrolytic cleaning, activated carbon filters of this type release VOCs that have been absorbed therein again.

Out of EP 2 669 583 A1 it is also known to conduct fumes in a cooking appliance through a volume of cooling water in order to dehumidify and cool the fumes. With such a device, however, the fumes cannot be sufficiently freed from VOCs, especially during pyrolytic cleaning.

Description of the invention

Proceeding from this situation, it is an object of the present invention to reduce odor nuisance in the vicinity of a cooking appliance, in particular during pyrolytic cleaning.

The object of the invention is solved by the features of the independent main claims. Advantageous configurations are specified in the dependent claims. As far as technically possible, the teachings of the subclaims can be combined with the teachings of the main and subclaims in any way.

In particular, the object is therefore achieved by a cooking appliance as described at the outset, with at least one water trap formed by a volume of water for cooling the vapor being arranged in the channel, with the vapor being guided through the volume of water or along the volume of water, and with at least one Adsorption filter is arranged for removing volatile organic compounds from the vapors, wherein the adsorption filter is arranged in a first position of the channel downstream of the water trap, so that the vapors flows through the water trap and then the adsorption filter, starting from the cooking chamber.

Advantageous aspects of the claimed invention are explained below and preferred modified embodiments of the invention are further described below. Explanations, in particular on advantages and definitions of features, are basically descriptive and preferred, but not limiting, examples. If an explanation is limiting, this is expressly mentioned.

The vapor can be guided through the volume of water in the water trap, for example by means of a lance immersed in the volume of water or by the volume of water flowing or running through the channel in a transverse direction. However, the vapor can also be guided along the water volume, in which case a material separation can be provided or the vapor can flow along a surface of the water volume. The water of the water volume is preferably replaceable.

In any case, the water trap ensures that the vapor is cooled and VOCs dissolved in the vapor condense out, so that the vapor is first cleaned. Insofar as the vapor and the water volume are in material contact, VOCs also go into the water volume and are dissolved there. The water trap can release VOC from the vapor up to the saturation vapor pressure.

By the water trap then provided in the flow path of the vapor Adsorption filter, the vapor is cleaned of VOCs a second time, with the vapor being lowered to a temperature by flowing through the water trap, which allows effective cleaning in the adsorption filter.

The combination of the first cleaning with simultaneous cooling and the second cleaning at a reduced temperature releases vapors that are largely free of VOCs and therefore odorless into the environment of the cooking appliance, particularly when the cooking appliance is pyrolytically cleaned.

In one embodiment, the adsorption filter is arranged in a second position of the duct directly downstream of the cooking chamber, so that the vapor flows through the adsorption filter first, starting from the cooking chamber. It is then possible by means of heated vapors to regenerate the adsorption filter, i.e. to release VOCs absorbed therein and emit them into the environment. If such a regeneration is stretched out over a sufficient period of time, a VOC load from exhaust air emitted into the environment can be kept below an odor limit. The adsorption filter then acts as a buffer storage during pyrolysis, causing a stretching of the time over which the VOCs are released into the environment.

In one configuration of this embodiment, the water trap is arranged downstream of the adsorption filter in the second position of the duct, so that the vapor flows from the cooking chamber first through the adsorption filter and then through the water trap. Cooling then takes place during regeneration and, if necessary, additional cleaning of the exhaust air from the regeneration of the adsorption filter in the water trap.

The channel is particularly preferably set up so that the vapor flows through the adsorption filter in the first position of the channel in a first direction and in the second position of the channel in a second direction opposite to the first direction. The regeneration of the adsorption filter is then supported by the forces resulting from the flow and is therefore simplified.

The cooking appliance preferably has means, in particular at least one multi-way valve, for selectively setting the first position of the channel or the second position of the channel. For example, the second position is set by means of this center following a pyrolytic cleaning of the cooking appliance carried out in the first position of the channel, in order to regenerate the adsorption filter again in a subsequent method step.

The adsorption filter preferably has activated carbon, zeolites, hypercrosslinked polymers and/or metal-organic framework compounds as the filter medium. The adsorption filter can also have several materials.

The object is also achieved by a method for cleaning the cooking chamber in a cooking appliance as described above, in which a pyrolysis temperature is set in the cooking chamber in a first step, with vapors arising in the cooking chamber when the pyrolysis temperature is set in the first position of the channel starting from the cooking chamber first through the water trap for cooling, then through the adsorption filter to remove volatile organic compounds and finally into the environment of the cooking appliance. As a result of the method, the vapor is emitted into the environment of the cooking appliance with a particularly low VOC load or odor load in accordance with the advantages described above.

In a second step, a regeneration temperature is preferably set in the cooking chamber, with vapors occurring in the cooking chamber at the regeneration temperature in a second position of the duct starting from the cooking chamber first for regenerating the adsorption filter through the adsorption filter, in particular subsequently for cooling through the water trap and finally into the vicinity of the cooking appliance. In this way, the adsorption filter is regenerated after cleaning and is available regenerated for further cleaning. Insofar as the vapor is conducted through the water trap downstream of the adsorption filter, this serves to cool the vapor before it is blown out into the environment. Depending on the remaining VOC load, the vapor can also be cleaned by the water trap to further minimize the odor load. The vapor is preferably guided through the adsorption filter in the first position of the duct in the first direction and in the second position of the duct in the second direction.

If the VOCs occurring during cleaning are first absorbed in the water trap and the adsorption filter and then emitted into the environment during later regeneration, the sum of the VOCs is emitted over a longer period of time than they occur in the cooking chamber. In this way, a critical concentration corresponding to an olfactory perceptibility of VOCs in the exhaust air emitted or the vapor emitted is not exceeded at any time. In particular, it is assumed that the VOC are distributed in the vicinity of the cooking appliance and are not locally concentrated. The adsorption filter thus acts as a buffer storage.

The pyrolysis temperature is, for example, more than 250°C, preferably more than 300°C. The pyrolysis temperature can be up to 500°C in particular. At such a temperature, the cooking chamber is reliably cleaned, in particular from organic impurities. The pyrolysis temperature is set in particular in such a way that the vapor in the channel can be sufficiently cleaned and that the vapor in the cold trap can be sufficiently cooled to be effectively further cleaned in the adsorption filter. The vapor is particularly preferably cooled to a temperature of less than 50° C. in the water trap in the first step.

Furthermore, the regeneration temperature is preferably less than 250° C., the adsorption filter being cleaned in this temperature range, but without generating too high a VOC load, which would lead to an odor nuisance in the vicinity of the cooking appliance.

character list

The invention is explained in more detail below with reference to the accompanying drawings using preferred exemplary embodiments. The wording figure is abbreviated to figure in the drawings.

• 1 eine schematische Darstellung von Komponenten eines Gargeräts nach einem Aspekt der Erfindung in einem Ausführungsbeispiel; und
• 2 eine Darstellung des zeitlichen Verlaufs mehrerer Verfahrensgrößen bei einem Verfahren nach einem Aspekt der Erfindung.

Show in the drawings

• 1 a schematic representation of components of a cooking appliance according to an aspect of the invention in an embodiment; and
• 2 a representation of the time course of several process variables in a method according to one aspect of the invention.

Detailed description of the exemplary embodiments

1 shows a schematic representation of a cooking appliance 1 with a cooking chamber 2, with a duct 3 branching off from the cooking chamber 2, via which vapors can be discharged from the cooking chamber 2 into an environment 4 of the cooking appliance 1. A first position 3.1 of the channel 3 is shown by a solid line, while a second position 3.2 of the channel 3 is shown by a dashed line. A multi-way valve 5 is provided for selecting between the first position 3.1 and the second position 3.2.

A water trap 6 formed by a volume of water (not shown) and an adsorption filter 7 embodied, for example, as an activated carbon filter are arranged in the channel 3 . In the first position 3.1, the vapor from the cooking chamber 2 is first guided in a first direction 8.1 through the water trap 6, then in the first direction 8.1 through the adsorption filter 7 and finally into the environment 4. In the second position 3.2, the vapor from the cooking chamber 2 is first guided in a second direction 8.2 through the adsorption filter 7, then in the second direction 8.2 through the water trap 6 and finally via another valve 9 into the environment 4. The valve 9 is used to block the flow path when the channel 3 is in the first position 3.1.

2 shows a diagram with exemplary curves of different variables in a method for cleaning the cooking chamber 2 according to one aspect of the invention, the time being shown on the x-axis and the VOC load at individual points in the channel 3 and on the y-axis the temperature in the cooking chamber 2. The time course of the method is divided by a time limit 10 into a first step before the time limit 10 and a second step after the time limit 10. A first profile 11.1 corresponds to a cooking chamber temperature. A second course 11.2 corresponds to the VOC load in the cooking chamber 2 or at the entrance of the duct 3 on the cooking chamber side before it flows through the water trap 6 or the adsorption filter 7. A third course 11.3 corresponds to the VOC load behind a water trap 6 in a vapor duct, in which only one such water trap 6 is arranged, with this VOC load corresponding to the VOC load behind the water trap 6 in the first method step. A fourth course 11.4 corresponds to the VOC load at the outlet of the channel 3 to the environment of the cooking appliance 1.

In the first step, the temperature is initially set to a pyrolysis temperature 12, as a result of which the VOC load in the cooking chamber 2 rises sharply. The VOC load behind the water trap 6 follows this VOC load in the cooking chamber 2, but is already greatly reduced by the cleaning in the water trap 6. The VOC load at the outlet of the channel 3, ie after the adsorption filter 7, in turn follows the VOC load after the water trap 6 until it reaches a minimum. If the minimum is reached, the multi-way valve 5 is switched over and the channel 3 is brought into the second position 3.1. The temperature in the cooking chamber 2 is set to a regeneration temperature 13 for this point in time, at which the time limit 10 lies. From the time limit 10, the VOC load at the outlet is determined by the regeneration of the adsorption filter 7 and is constant as a result of the regeneration temperature 13. Overall, the VOC load at the outlet of the channel 3 is significantly reduced compared to the concentration in the cooking chamber 2 and also compared to the state after the water trap 6.

Reference List

1

cooking appliance

2

cooking chamber

3

channel

3.1

first position of the channel

3.2

second position of the channel

4

Vicinity

5

multi-way valve

6

Water falls

7

adsorption filter

8.1

first direction

8.2

second direction

9

Valve

10

time limit

11.1

first course

11.2

second course

11.3

third course

11.4

fourth course

12

pyrolysis temperature

13

regeneration temperature

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• EP 0831277 A1 [0003]
• EP 1217306 A2 [0003]
• DE 102008023310 A1 [0004]
• EP 2669583 A1 [0005]

Claims (12)

Cooking appliance (1) with a housing and a cooking chamber (2) arranged in the housing and with a duct (3) arranged in the housing for discharging vapors from the cooking chamber (2) into an environment (4) of the cooking appliance (1), at least one water trap (6) formed by a water volume for cooling the vapor is arranged in the channel (3), the vapor being guided through the water volume or along the water volume, and wherein in the channel (3) at least one adsorption filter (7 ) is arranged to remove volatile organic compounds from the fumes, wherein the adsorption filter (7) is arranged in a first position (3.1) of the duct (3) downstream of the water trap (6), so that the fumes, starting from the cooking chamber (2 ) first flows through the water trap (6) and then through the adsorption filter (7). Cooking appliance (1) after claim 1 , wherein the adsorption filter (7) is arranged in a second position (3.2) of the channel (3) immediately downstream of the cooking chamber (2), so that the vapors, starting from the cooking chamber (2), first flow through the adsorption filter (7). Cooking appliance (1) after claim 2 , wherein the water trap (6) is arranged in the second position (3.2) of the channel (3) downstream of the adsorption filter (7), so that the vapors starting from the cooking chamber (2) first pass the adsorption filter (7) and then the water trap ( 6) flows through. Cooking appliance (1) after claim 2 or 3 , wherein the channel (3) is set up so that the vapors flow through the adsorption filter (7) in the first position (3.1) of the channel (3) in a first direction (8.1) and in the second position (3.2) of the channel (3 ) in a second direction (8.2) opposite to the first direction (8.1). Cooking appliance (1) according to one of claims 2 until 4 , having means, in particular at least one multi-way valve (5), for selectively setting the first position (3.1) of the channel (3) or the second position (3.2) of the channel (3). Cooking appliance (1) according to one of the preceding claims, in which the adsorption filter (7) has activated carbon, zeolites, hyper-crosslinked polymers and/or metal-organic framework compounds as the filter medium. Method for cleaning the cooking chamber (2) in a cooking appliance (1) according to one of the preceding claims, wherein a pyrolysis temperature (12) is set in the cooking chamber (2) in a first step, wherein in the cooking chamber (2) when setting the pyrolysis temperature (12) Vapors arising in the first position (3.1) of the duct (3) starting from the cooking chamber (2) first for cooling through the water trap (6), then for removing volatile organic compounds through the adsorption filter (7) and finally in the area (4) of the cooking appliance (1) is guided. procedure after claim 7 , wherein in a second step a regeneration temperature (13) is set in the cooking chamber (2), wherein in the cooking chamber (2) at the regeneration temperature (13) vapors arising in a second position (3.2) of the duct (3) starting from the Cooking chamber (2) first for regenerating the adsorption filter (7) through the adsorption filter (7), in particular then for cooling through the water trap (6) and finally into the environment (4) of the cooking appliance (1). procedure after claim 8 , wherein the vapors in the first position (3.1) of the channel (3) in a first direction (8.1) and in the second position (3.2) of the channel (3) in a second direction (8.2) opposite to the first direction (8.1) through the adsorption filter (7). Procedure according to one of Claims 7 until 9 , wherein the pyrolysis temperature (12) is more than 250°C, in particular more than 300°C. Procedure according to one of Claims 7 until 10 , wherein the vapor in the first step in the water trap (6) is cooled to a temperature of less than 50 ° C. Procedure according to one of Claims 7 until 11 , wherein the regeneration temperature (13) is less than 250°C.

Images